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2024 Volume 40 Issue 1
2024, 40(1):
Abstract:
2024, 40(1): 1-14
doi: 10.11862/CJIC.20230364
Abstract:
Metal-organic framework (MOF) materials have attracted widespread attention in the field of third-order nonlinear optics (NLO) due to their customizable structure and flexible and controllable coordination modes. Compared with the liquid dispersion, the third-order NLO performance of MOFs in the solid state is particularly important. This provides a deeper understanding of the inherent optical performance of MOFs and helps realize the practical application in optical devices. However, it is difficult to directly study the NLO performance of MOFs in the solid state due to the presence of scattering and limitations of transmittance. In order to study the NLO performance of MOFs in the solid state, the most feasible strategy is to process MOFs into films with better transmittance. MOF film materials not only inherit the MOF inherent NLO performance but also combine the high transmittance and flexible mechanical properties of the film. This review analyzes and summarizes the preparation methods of MOF films and related work on NLO performance research. The prospects of MOF films in third-order NLO performance are proposed in this review.
Metal-organic framework (MOF) materials have attracted widespread attention in the field of third-order nonlinear optics (NLO) due to their customizable structure and flexible and controllable coordination modes. Compared with the liquid dispersion, the third-order NLO performance of MOFs in the solid state is particularly important. This provides a deeper understanding of the inherent optical performance of MOFs and helps realize the practical application in optical devices. However, it is difficult to directly study the NLO performance of MOFs in the solid state due to the presence of scattering and limitations of transmittance. In order to study the NLO performance of MOFs in the solid state, the most feasible strategy is to process MOFs into films with better transmittance. MOF film materials not only inherit the MOF inherent NLO performance but also combine the high transmittance and flexible mechanical properties of the film. This review analyzes and summarizes the preparation methods of MOF films and related work on NLO performance research. The prospects of MOF films in third-order NLO performance are proposed in this review.
2024, 40(1): 15-32
doi: 10.11862/CJIC.20230383
Abstract:
The green energy conversion and storage technologies such as water splitting and zinc -air batteries (ZABs) open a new path to solve the energy crisis and achieve carbon neutrality goals. However, the practical applications of these technologies are largely limited by the sluggish kinetics of hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR). Therefore, it is urgent to develop efficient and stable electrocatalysts to effectively reduce reaction overpotential and accelerate the processes of electrocatalytic reactions. Metal-organic frameworks (MOFs) have emerged as one of the most widely investigated materials in catalysis mainly due to their flexible and tunable compositions and precise and controllable structures. This article mainly introduces the recent research progress of MOFs-based electrocatalysts in water splitting and ZABs with emphasis on their preparation strategies and architecture characteristics. Finally, some summaries and outlooks of the existing problems and development trends in this field are put forward.
The green energy conversion and storage technologies such as water splitting and zinc -air batteries (ZABs) open a new path to solve the energy crisis and achieve carbon neutrality goals. However, the practical applications of these technologies are largely limited by the sluggish kinetics of hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR). Therefore, it is urgent to develop efficient and stable electrocatalysts to effectively reduce reaction overpotential and accelerate the processes of electrocatalytic reactions. Metal-organic frameworks (MOFs) have emerged as one of the most widely investigated materials in catalysis mainly due to their flexible and tunable compositions and precise and controllable structures. This article mainly introduces the recent research progress of MOFs-based electrocatalysts in water splitting and ZABs with emphasis on their preparation strategies and architecture characteristics. Finally, some summaries and outlooks of the existing problems and development trends in this field are put forward.
2024, 40(1): 33-53
doi: 10.11862/CJIC.20230380
Abstract:
Metal-organic complex materials are widely used in security and anti-counterfeiting, information storage, intelligent sensing, display devices, white light lighting, and other fields based on their structural diversity and controllable luminescence properties. In this review, the research progress of single-component metal-organic complexes in white light luminescence is introduced in detail. According to the five categories of Au (Ⅰ)/Ag(Ⅰ)/Cu(Ⅰ) complexes, Zn(Ⅱ)/Cd(Ⅱ) complexes, Eu(Ⅲ)&Tb(Ⅲ) co-doped Ln(Ⅲ) complexes, dye-doped complexes, other main group elements/ transition elements/lanthanide elements doped/multi-element doped complexes, the structural characteristics, luminescence mechanism, white light luminescence composition and white light performance index of complexes are analyzed. The construction strategies of white light emission materials of different types of complexes are generalized. The advantages of metal-organic complex materials as white light candidate materials are summarized, and the problems to be further solved are put forward from two aspects of theoretical research and practical application, to realize the industrial production and application of metal-organic complex luminescent materials as soon as possible.
Metal-organic complex materials are widely used in security and anti-counterfeiting, information storage, intelligent sensing, display devices, white light lighting, and other fields based on their structural diversity and controllable luminescence properties. In this review, the research progress of single-component metal-organic complexes in white light luminescence is introduced in detail. According to the five categories of Au (Ⅰ)/Ag(Ⅰ)/Cu(Ⅰ) complexes, Zn(Ⅱ)/Cd(Ⅱ) complexes, Eu(Ⅲ)&Tb(Ⅲ) co-doped Ln(Ⅲ) complexes, dye-doped complexes, other main group elements/ transition elements/lanthanide elements doped/multi-element doped complexes, the structural characteristics, luminescence mechanism, white light luminescence composition and white light performance index of complexes are analyzed. The construction strategies of white light emission materials of different types of complexes are generalized. The advantages of metal-organic complex materials as white light candidate materials are summarized, and the problems to be further solved are put forward from two aspects of theoretical research and practical application, to realize the industrial production and application of metal-organic complex luminescent materials as soon as possible.
2024, 40(1): 54-70
doi: 10.11862/CJIC.20230387
Abstract:
The central dopamine system plays a crucial role in the pathophysiology of various neurobehavioral disorders. Positron emission tomography (PET) imaging has been instrumental in studying dopamine biochemical processes in the living brain. PET imaging utilizes positron-emitting radionuclide 11C/18F-labelled tracers to assess dopamine synthesis, vesicle storage, synaptic release, receptor binding, and reuptake processes by binding to specific targets in the dopamine nervous system. This advancement has significantly contributed to research in neurology, psychiatry, drug abuse and addiction, and therapeutic drug development. This article provides a comprehensive review of the progress in 11C/18F-labelled PET imaging agents targeting amino acid decarboxylase, dopamine transporters, dopamine receptors, and vesicular monoamine transporters.
The central dopamine system plays a crucial role in the pathophysiology of various neurobehavioral disorders. Positron emission tomography (PET) imaging has been instrumental in studying dopamine biochemical processes in the living brain. PET imaging utilizes positron-emitting radionuclide 11C/18F-labelled tracers to assess dopamine synthesis, vesicle storage, synaptic release, receptor binding, and reuptake processes by binding to specific targets in the dopamine nervous system. This advancement has significantly contributed to research in neurology, psychiatry, drug abuse and addiction, and therapeutic drug development. This article provides a comprehensive review of the progress in 11C/18F-labelled PET imaging agents targeting amino acid decarboxylase, dopamine transporters, dopamine receptors, and vesicular monoamine transporters.
2024, 40(1): 71-78
doi: 10.11862/CJIC.20230228
Abstract:
Reactions of (Et4N) (Tp*WS3) (A) (Tp* =hydridotris(3, 5 -dimethylpyrazol -1 -yl)borate) and Cu (Ⅰ) salts [Cu(MeCN)4]PF6 with di(pyridin-4-yl)sulfane (L1) or bis(4-(pyridin-4-yl)phenyl)methanone (L2) gave rise to two W/Cu/ S cluster-based supramolecular compounds with the formula of [Tp*WS3Cu2(L1)]2(PF6)2·2MeCN·2CHCl3 (1·2MeCN·2CHCl3) and [Tp*WS3Cu2(L2)(MeCN)]2(PF6)2·4MeCN (2·4MeCN), respectively. Both cluster-based supramolecular compounds were structurally characterized by single -crystal X -ray diffraction, 1H NMR, MS, IR, UV -Vis, and elemental analysis. Single crystal X-ray diffraction demonstrates that both compounds are cationic cluster-based supramolecule frames with similar butterfly-like cores. 1H NMR and high-resolution electrospray ionization mass spectrometry (HRESI -MS) demonstrated their stability in DMF solution. In addition, the Z -scan measurement reveals the third-order nonlinear optical responses of 1·2MeCN·2CHCl3 and 2·4MeCN were enhanced compared to that of their precursor A.
Reactions of (Et4N) (Tp*WS3) (A) (Tp* =hydridotris(3, 5 -dimethylpyrazol -1 -yl)borate) and Cu (Ⅰ) salts [Cu(MeCN)4]PF6 with di(pyridin-4-yl)sulfane (L1) or bis(4-(pyridin-4-yl)phenyl)methanone (L2) gave rise to two W/Cu/ S cluster-based supramolecular compounds with the formula of [Tp*WS3Cu2(L1)]2(PF6)2·2MeCN·2CHCl3 (1·2MeCN·2CHCl3) and [Tp*WS3Cu2(L2)(MeCN)]2(PF6)2·4MeCN (2·4MeCN), respectively. Both cluster-based supramolecular compounds were structurally characterized by single -crystal X -ray diffraction, 1H NMR, MS, IR, UV -Vis, and elemental analysis. Single crystal X-ray diffraction demonstrates that both compounds are cationic cluster-based supramolecule frames with similar butterfly-like cores. 1H NMR and high-resolution electrospray ionization mass spectrometry (HRESI -MS) demonstrated their stability in DMF solution. In addition, the Z -scan measurement reveals the third-order nonlinear optical responses of 1·2MeCN·2CHCl3 and 2·4MeCN were enhanced compared to that of their precursor A.
2024, 40(1): 79-87
doi: 10.11862/CJIC.20230284
Abstract:
Designing efficient oxygen evolution reaction (OER) catalysts is crucial for water splitting to produce hydrogen. Based on the catalytic activity of transition metal selenides (TMSe) and the structural characteristics of metal-organic frameworks (MOFs), the work proposed a strategy to compound MOFs and TMSe. The composite material grew on conductive base nickel foam (NF) inherited the advantages of the two materials, and the defects of poor conductivity of MOFs and easy aggregation of TMSe were effectively improved. The MoSe2/Co -MOF/NF showed excellent electrochemical performance in alkaline solution, and its overpotential was only 242 mV at 10 mA·cm-2, the Tafel slope was 50.64 mV·dec-1. In addition, it exhibited good stability in an alkaline solution after 1 000 cyclic voltammetry (CV) cycles and 30 h constant voltage electrolysis test.
Designing efficient oxygen evolution reaction (OER) catalysts is crucial for water splitting to produce hydrogen. Based on the catalytic activity of transition metal selenides (TMSe) and the structural characteristics of metal-organic frameworks (MOFs), the work proposed a strategy to compound MOFs and TMSe. The composite material grew on conductive base nickel foam (NF) inherited the advantages of the two materials, and the defects of poor conductivity of MOFs and easy aggregation of TMSe were effectively improved. The MoSe2/Co -MOF/NF showed excellent electrochemical performance in alkaline solution, and its overpotential was only 242 mV at 10 mA·cm-2, the Tafel slope was 50.64 mV·dec-1. In addition, it exhibited good stability in an alkaline solution after 1 000 cyclic voltammetry (CV) cycles and 30 h constant voltage electrolysis test.
2024, 40(1): 88-98
doi: 10.11862/CJIC.20230308
Abstract:
Coal tar pitch-based porous carbon was prepared by carbonizing the carbon source of coal tar pitch and flame retardant of magnesium hydroxide-zinc borate composite salt directly in the air, and its electrochemical performance was explored. Thanks to the synergistic effect of flame retardants on flame retardancy, activation, and doping functionalization, coal tar pitch-based porous carbon with high yield (55.1%), multi-heteroatom doping, and hierarchical structure was obtained. As the electrode material for supercapacitor, the specific capacitance can reach 344 F·g-1 at a current density of 0.5 A·g-1 in a three-electrode system. In addition, the flexible capacitor assembled with the prepared porous carbon and chitosan amino acid proton salt gel electrolyte has an energy density of 29.3 Wh·kg-1, the capacitance remained 96.9% after 50 000 cycles, and it can work normally in the temperature range from -25 to 75 ℃, which had a wide operating temperature range.
Coal tar pitch-based porous carbon was prepared by carbonizing the carbon source of coal tar pitch and flame retardant of magnesium hydroxide-zinc borate composite salt directly in the air, and its electrochemical performance was explored. Thanks to the synergistic effect of flame retardants on flame retardancy, activation, and doping functionalization, coal tar pitch-based porous carbon with high yield (55.1%), multi-heteroatom doping, and hierarchical structure was obtained. As the electrode material for supercapacitor, the specific capacitance can reach 344 F·g-1 at a current density of 0.5 A·g-1 in a three-electrode system. In addition, the flexible capacitor assembled with the prepared porous carbon and chitosan amino acid proton salt gel electrolyte has an energy density of 29.3 Wh·kg-1, the capacitance remained 96.9% after 50 000 cycles, and it can work normally in the temperature range from -25 to 75 ℃, which had a wide operating temperature range.
2024, 40(1): 99-110
doi: 10.11862/CJIC.20230303
Abstract:
2 -(N, N -bis(diphenylphosphino)methyl)aminopyridine (bdppmapy) was selected as a phosphine ligand, dipyrido[3, 2-a∶2′, 3′-c]phenazine (dppz) as a nitrogen ligand, and [Cu(CH3CN)4]BF4 as a copper salt to react at room temperature. Three new Cu (Ⅰ) complexes were prepared, namely [Cu(dppz) (bdppmapy)]2(BF4)2·H2O (CuBF4-1), [Cu(dppz) (bdppmapy)]BF4 (CuBF4-2), and [Cu(dppz) (bdppmapy)]BF4 (CuBF4-3). Single crystals of CuBF4-1 and CuBF4-3 were obtained. The phenomenon of single-crystal-to-single-crystal conversion was found, and the influence of solvent molecules on the structure and photophysical properties of coordination geometry was explored. The structures of complexes CuBF4-1 and CuBF4-3 were determined by single-crystal X-ray diffraction, and the structures of the three complexes were characterized by powder X-ray diffraction (PXRD), IR, and hydrogen/phosphorus NMR (1H/31P NMR). The photophysical properties of the complexes were characterized and analyzed by UV-Vis absorption spectrum, fluorescence spectrum, fluorescence lifetime, and quantum yield. The differences in the luminescence properties of the complexes were compared, and the influence of solvent molecules on the structure and photophysical properties of coordination geometry was discussed. Terahertz time-domain spectroscopy provided assistance in the study of complexes.
2 -(N, N -bis(diphenylphosphino)methyl)aminopyridine (bdppmapy) was selected as a phosphine ligand, dipyrido[3, 2-a∶2′, 3′-c]phenazine (dppz) as a nitrogen ligand, and [Cu(CH3CN)4]BF4 as a copper salt to react at room temperature. Three new Cu (Ⅰ) complexes were prepared, namely [Cu(dppz) (bdppmapy)]2(BF4)2·H2O (CuBF4-1), [Cu(dppz) (bdppmapy)]BF4 (CuBF4-2), and [Cu(dppz) (bdppmapy)]BF4 (CuBF4-3). Single crystals of CuBF4-1 and CuBF4-3 were obtained. The phenomenon of single-crystal-to-single-crystal conversion was found, and the influence of solvent molecules on the structure and photophysical properties of coordination geometry was explored. The structures of complexes CuBF4-1 and CuBF4-3 were determined by single-crystal X-ray diffraction, and the structures of the three complexes were characterized by powder X-ray diffraction (PXRD), IR, and hydrogen/phosphorus NMR (1H/31P NMR). The photophysical properties of the complexes were characterized and analyzed by UV-Vis absorption spectrum, fluorescence spectrum, fluorescence lifetime, and quantum yield. The differences in the luminescence properties of the complexes were compared, and the influence of solvent molecules on the structure and photophysical properties of coordination geometry was discussed. Terahertz time-domain spectroscopy provided assistance in the study of complexes.
2024, 40(1): 111-123
doi: 10.11862/CJIC.20230335
Abstract:
Two novel metal coordination compounds [Co3(L1)2Cl6]n (1) and {[Cu(L1)(SO4)]·2CH3OH}n (2), where L1= 2, 2′, 2″-tri(1-benzimidazolyl) ethylamine, have been synthesized by solvothermal method. L1 is a neutral benzimidazole tripod ligand. Single crystal X-ray diffraction analysis shows that compound 1 is a 1D chain structure and compound 2 is a 3D structure. The purity of compounds 1 and 2 was characterized by infrared spectroscopy and powder X-ray diffraction. Thermogravimetric analysis shows that compounds 1 and 2 are heat-resistant materials. The iodine adsorption experiments show that they have high performance of capturing iodine in cyclohexane solution and gaseous iodine and have good recycling ability. At the same time, their adsorption kinetics are most suitable for the quasi-second-order model, and the adsorption process is mainly chemisorption. According to the adsorption mechanism, the structures of the compounds contain active groups such as benzene and N heterocyclic ring, which indirectly increases the adsorption site with iodine and the chemical reactivity with iodine, improving the removal rate of iodine.
Two novel metal coordination compounds [Co3(L1)2Cl6]n (1) and {[Cu(L1)(SO4)]·2CH3OH}n (2), where L1= 2, 2′, 2″-tri(1-benzimidazolyl) ethylamine, have been synthesized by solvothermal method. L1 is a neutral benzimidazole tripod ligand. Single crystal X-ray diffraction analysis shows that compound 1 is a 1D chain structure and compound 2 is a 3D structure. The purity of compounds 1 and 2 was characterized by infrared spectroscopy and powder X-ray diffraction. Thermogravimetric analysis shows that compounds 1 and 2 are heat-resistant materials. The iodine adsorption experiments show that they have high performance of capturing iodine in cyclohexane solution and gaseous iodine and have good recycling ability. At the same time, their adsorption kinetics are most suitable for the quasi-second-order model, and the adsorption process is mainly chemisorption. According to the adsorption mechanism, the structures of the compounds contain active groups such as benzene and N heterocyclic ring, which indirectly increases the adsorption site with iodine and the chemical reactivity with iodine, improving the removal rate of iodine.
2024, 40(1): 124-134
doi: 10.11862/CJIC.20230359
Abstract:
The synthesis of zeolite molecular sieves (referred to as GFS) using fly ash as a raw material was carried out in three stages. The method employed for this synthesis was called"combined modification three-step synthesis", which involved ultrasonic-assisted alkali fusion microwave crystallization combined with waste glass/13X seed/ NaH2PO4 impregnation. To compare the results, traditional alkali fusion hydrothermal synthesis was used to synthesize zeolite molecular sieves (referred to as FS). In addition, zeolite molecular sieves (referred to as WFS) were synthesized using the"three-step synthesis"method of ultrasonic-assisted alkali fusion microwave crystallization. The materials were characterized using various techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), energy-dispersive spectroscopy (EDS), and N2 adsorption-desorption analysis to determine their composition, morphology, and structure. The results indicated that WFS and GFS exhibited higher specific surface areas and well-developed mesopores and micropores compared to FS. Additionally, the crystal type of zeolite molecular sieves shifted from NaA single crystal to NaA/NaX twin crystal. Ammonia nitrogen adsorption experiments revealed that GFS (56.01 mg·g-1) showed better adsorption performance than WFS (49.17 mg·g-1) and FS (39.75 mg·g-1). The adsorption of ammonia nitrogen follows the second-order kinetics model and the Langmuir model, as indicated by kinetic and thermodynamic data. This process primarily relies on ion exchange and is both spontaneous and exothermic. Lower temperatures enhance the adsorption of ammonia nitrogen.
The synthesis of zeolite molecular sieves (referred to as GFS) using fly ash as a raw material was carried out in three stages. The method employed for this synthesis was called"combined modification three-step synthesis", which involved ultrasonic-assisted alkali fusion microwave crystallization combined with waste glass/13X seed/ NaH2PO4 impregnation. To compare the results, traditional alkali fusion hydrothermal synthesis was used to synthesize zeolite molecular sieves (referred to as FS). In addition, zeolite molecular sieves (referred to as WFS) were synthesized using the"three-step synthesis"method of ultrasonic-assisted alkali fusion microwave crystallization. The materials were characterized using various techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), energy-dispersive spectroscopy (EDS), and N2 adsorption-desorption analysis to determine their composition, morphology, and structure. The results indicated that WFS and GFS exhibited higher specific surface areas and well-developed mesopores and micropores compared to FS. Additionally, the crystal type of zeolite molecular sieves shifted from NaA single crystal to NaA/NaX twin crystal. Ammonia nitrogen adsorption experiments revealed that GFS (56.01 mg·g-1) showed better adsorption performance than WFS (49.17 mg·g-1) and FS (39.75 mg·g-1). The adsorption of ammonia nitrogen follows the second-order kinetics model and the Langmuir model, as indicated by kinetic and thermodynamic data. This process primarily relies on ion exchange and is both spontaneous and exothermic. Lower temperatures enhance the adsorption of ammonia nitrogen.
2024, 40(1): 135-144
doi: 10.11862/CJIC.20230394
Abstract:
Two novel lanthanide bisphosphonate complexes containing Keggin polyoxometalates [Eu(L)4]PW12O40· 2CH3CN (1) and [Tb(L)3(H2O)]PW12O40 (2) (L=tetraethyl ethylenediphosphonate) were synthesized in a mixed solvent of acetonitrile and deionized water. The properties of the two complexes were characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectroscopy, powder X-ray diffraction, thermogravimetric analysis and terahertz time domain spectroscopy. The crystal structure and intermolecular weak force of the complexes were analyzed, and the luminescence and other properties of the complexes were studied. The single crystal X-ray diffraction indicates that the structure of complex 1 is a twisted tetragonal antiprism with Eu (Ⅲ) as the center and L as the ligands chelate. The structure of complex 2 is a twisted single-capped octahedral with Tb(Ⅲ) as the center and L and H2O as the ligands. The luminescence spectra indicate that all emission peaks of complexes 1 and 2 are due to charge transfer within the metal. In addition, terahertz time-domain spectroscopy has helped in the study of complexes 1 and 2.
Two novel lanthanide bisphosphonate complexes containing Keggin polyoxometalates [Eu(L)4]PW12O40· 2CH3CN (1) and [Tb(L)3(H2O)]PW12O40 (2) (L=tetraethyl ethylenediphosphonate) were synthesized in a mixed solvent of acetonitrile and deionized water. The properties of the two complexes were characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectroscopy, powder X-ray diffraction, thermogravimetric analysis and terahertz time domain spectroscopy. The crystal structure and intermolecular weak force of the complexes were analyzed, and the luminescence and other properties of the complexes were studied. The single crystal X-ray diffraction indicates that the structure of complex 1 is a twisted tetragonal antiprism with Eu (Ⅲ) as the center and L as the ligands chelate. The structure of complex 2 is a twisted single-capped octahedral with Tb(Ⅲ) as the center and L and H2O as the ligands. The luminescence spectra indicate that all emission peaks of complexes 1 and 2 are due to charge transfer within the metal. In addition, terahertz time-domain spectroscopy has helped in the study of complexes 1 and 2.
2024, 40(1): 145-154
doi: 10.11862/CJIC.20230395
Abstract:
In this work, a facile and cost-effective solid-state reaction method for the synthesis of the nanocomposites (denoted as FeCoS2⊂NSC) of N, S-codoped carbon-confined FeCoS2 nanocrystalline was presented. By directly mixing cobalt acetate tetrahydrate, ferrous acetate, o-vanillin and o-phenylenediamine with a molar ratio of 1∶1∶4∶2 at ambient temperature in the presence of sulfur powder, a self-assembly solid state reaction took place to give rise to the complexes of Co(Ⅱ) and Fe(Ⅱ) with a bis-Schiff base, which were evenly distributed in the sulfur powder surroundings. After subsequent annealing at an elevated temperature, simultaneous carbonization and sulfidization occurred, resulting in the in-situ formation of ultrafine FeCoS2 nanoparticles confined in N, S-codoped carbon matrices. The phase, morphology, composition, and content of each component in the nanocomposite were determined by powder X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The electrochemical sodium storage performance was tested by the cyclic voltammetry and galvanostatic charge-discharge techniques. The results showed that the average size of the FeCoS2 particles in the optimized nanocomposite (FeCoS2⊂NSC-7001) was ca. 3.4 nm, which was uniformly confined in the N, S-codoped carbon matrices. When FeCoS2⊂NSC-7001 was used as an anode material for sodium-ion batteries, it exhibited excellent electrochemical energy storage performance in terms of long-term cycling stability and rate capability. An anode prepared with FeCoS2⊂NSC-7001 nanocomposite exhibited significantly improved sodium-ion storage performance, where a large reversible charging capacity of 310.4 mAh·g-1 was obtained after 300 cycles at a current density of 0.1 A·g-1. Even when such an anode was cycled at a current density of 5 A·g-1, a reversible specific charging capacity of 146.0 mAh·g-1 can still be achieved, showing excellent electrochemical sodium storage performance.
In this work, a facile and cost-effective solid-state reaction method for the synthesis of the nanocomposites (denoted as FeCoS2⊂NSC) of N, S-codoped carbon-confined FeCoS2 nanocrystalline was presented. By directly mixing cobalt acetate tetrahydrate, ferrous acetate, o-vanillin and o-phenylenediamine with a molar ratio of 1∶1∶4∶2 at ambient temperature in the presence of sulfur powder, a self-assembly solid state reaction took place to give rise to the complexes of Co(Ⅱ) and Fe(Ⅱ) with a bis-Schiff base, which were evenly distributed in the sulfur powder surroundings. After subsequent annealing at an elevated temperature, simultaneous carbonization and sulfidization occurred, resulting in the in-situ formation of ultrafine FeCoS2 nanoparticles confined in N, S-codoped carbon matrices. The phase, morphology, composition, and content of each component in the nanocomposite were determined by powder X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The electrochemical sodium storage performance was tested by the cyclic voltammetry and galvanostatic charge-discharge techniques. The results showed that the average size of the FeCoS2 particles in the optimized nanocomposite (FeCoS2⊂NSC-7001) was ca. 3.4 nm, which was uniformly confined in the N, S-codoped carbon matrices. When FeCoS2⊂NSC-7001 was used as an anode material for sodium-ion batteries, it exhibited excellent electrochemical energy storage performance in terms of long-term cycling stability and rate capability. An anode prepared with FeCoS2⊂NSC-7001 nanocomposite exhibited significantly improved sodium-ion storage performance, where a large reversible charging capacity of 310.4 mAh·g-1 was obtained after 300 cycles at a current density of 0.1 A·g-1. Even when such an anode was cycled at a current density of 5 A·g-1, a reversible specific charging capacity of 146.0 mAh·g-1 can still be achieved, showing excellent electrochemical sodium storage performance.
2024, 40(1): 155-163
doi: 10.11862/CJIC.20230362
Abstract:
Carbon nanotubes-reduced graphene oxide (CNTs-rGO) three-dimensional aerogels were prepared using hydroxylated carbon nanotubes (CNT-OH) and graphene oxide (GO) as raw materials through redox self-assembly hydrothermal synthesis strategy. The effect of hydrothermal temperature on three-dimensional aerogels was investigated. The structure and morphology of the materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy (Raman) and X-ray photoelectron spectroscopy (XPS). The electrochemical test results indicate that the aerogel CNTs-rGO synthesized at 140 ℃ showed the best electrochemical performance, the specific capacitance at 1 A·g-1 current density was up to 294.65 F·g-1, and the shape of cyclic voltammetry curve at 50 mV·s-1 scanning speed was still similar to a rectangle, showing good reversibility. The assembled symmetrical supercapacitor had a maximum energy density of 3.744 Wh·kg-1 at a power density of 249.8 W·kg-1. After 10 000 cycles at 1 A·g-1, its capacitance retention and Coulombic efficiency were both about 100%. The excellent electrochemical performance is mainly attributed to the porous three -dimensional structure of CNTs -rGO composite material, which ensures rapid ion transport. Carbon nanotubes can not only overcome the sheet stacking problem of graphene, but also increase the specific surface area of the composite material, increase the reactive sites, and improve its electrochemical properties; at the same time, it can also provide electron transport channels and improve the conductivity of the material, so that the composite material has better mechanical and electrochemical properties.
Carbon nanotubes-reduced graphene oxide (CNTs-rGO) three-dimensional aerogels were prepared using hydroxylated carbon nanotubes (CNT-OH) and graphene oxide (GO) as raw materials through redox self-assembly hydrothermal synthesis strategy. The effect of hydrothermal temperature on three-dimensional aerogels was investigated. The structure and morphology of the materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy (Raman) and X-ray photoelectron spectroscopy (XPS). The electrochemical test results indicate that the aerogel CNTs-rGO synthesized at 140 ℃ showed the best electrochemical performance, the specific capacitance at 1 A·g-1 current density was up to 294.65 F·g-1, and the shape of cyclic voltammetry curve at 50 mV·s-1 scanning speed was still similar to a rectangle, showing good reversibility. The assembled symmetrical supercapacitor had a maximum energy density of 3.744 Wh·kg-1 at a power density of 249.8 W·kg-1. After 10 000 cycles at 1 A·g-1, its capacitance retention and Coulombic efficiency were both about 100%. The excellent electrochemical performance is mainly attributed to the porous three -dimensional structure of CNTs -rGO composite material, which ensures rapid ion transport. Carbon nanotubes can not only overcome the sheet stacking problem of graphene, but also increase the specific surface area of the composite material, increase the reactive sites, and improve its electrochemical properties; at the same time, it can also provide electron transport channels and improve the conductivity of the material, so that the composite material has better mechanical and electrochemical properties.
2024, 40(1): 164-172
doi: 10.11862/CJIC.20230356
Abstract:
Bridged and spirocyclic compounds are common concepts in the pure organic field. Herein, we extend these concepts to supramolecular chemistry and a synthetic strategy is exhibited. Three supramolecular bridged compounds [(Cp*Rh)6(μ-η2-η2-C2O4)2(μ-C2O4)(LA)2](OTf)6 (1), [(Cp*Rh)6(dhbq)2(pyrazine)(LA)2](OTf)8 (2), and [(Cp*Rh)6 (tpphz)2(bpea)(LA)2](OTf)12 (3), and a spirocyclic compound (Cp*Rh)12(bibzim)3Ru(LA)3(LB)3](OTf)10(PF6)4 (4), where LA =3,3′-di(pyridin-4-yl)-2,2′-bipyridine, OTf-=CF3SO3-, dhbq=2,5-dihydroxy-1,4-benzoquinone, tpphz=tetrapyrido[3,2-a∶2′,3′-c∶3″, 2″-h∶2''',3'''-j]phenazine, bpea=1,2-di(pyridin-4-yl)ethane, bibzim=2,2′-bisbenzimidazole, LB=4,4′-di(pyridin-4-yl)-1,1′-biphenyl, were obtained by introducing of additional chelating sites in rigid linear ligand through coordination-driven stepwise chemical self-assembly method and were characterized by single crystal X-ray diffraction method.
Bridged and spirocyclic compounds are common concepts in the pure organic field. Herein, we extend these concepts to supramolecular chemistry and a synthetic strategy is exhibited. Three supramolecular bridged compounds [(Cp*Rh)6(μ-η2-η2-C2O4)2(μ-C2O4)(LA)2](OTf)6 (1), [(Cp*Rh)6(dhbq)2(pyrazine)(LA)2](OTf)8 (2), and [(Cp*Rh)6 (tpphz)2(bpea)(LA)2](OTf)12 (3), and a spirocyclic compound (Cp*Rh)12(bibzim)3Ru(LA)3(LB)3](OTf)10(PF6)4 (4), where LA =3,3′-di(pyridin-4-yl)-2,2′-bipyridine, OTf-=CF3SO3-, dhbq=2,5-dihydroxy-1,4-benzoquinone, tpphz=tetrapyrido[3,2-a∶2′,3′-c∶3″, 2″-h∶2''',3'''-j]phenazine, bpea=1,2-di(pyridin-4-yl)ethane, bibzim=2,2′-bisbenzimidazole, LB=4,4′-di(pyridin-4-yl)-1,1′-biphenyl, were obtained by introducing of additional chelating sites in rigid linear ligand through coordination-driven stepwise chemical self-assembly method and were characterized by single crystal X-ray diffraction method.
2024, 40(1): 173-181
doi: 10.11862/CJIC.20230360
Abstract:
In this study, we successfully designed and synthesized selenium-doped carbon dots (Se-CDs) using easily available precursors of benzeneseleninic acid (BA) and o-phenylenediamine (o-PDA) through a one-step hydrothermal method. These Se-CDs emitted red-wavelength fluorescence and were utilized to develop a sensitive fluorescence sensor for detecting microRNA-21 (miR-21). By incorporating deoxyribonuclease Ⅰ (DNase Ⅰ)-mediated signal amplification, the detection limit for miR -21 was improved from 78 to 6.8 nmol·L-1. Furthermore, we observed desirable inhibitory activity of the Se-CDs against Gram-negative bacteria of Escherichia coli (E. coli).
In this study, we successfully designed and synthesized selenium-doped carbon dots (Se-CDs) using easily available precursors of benzeneseleninic acid (BA) and o-phenylenediamine (o-PDA) through a one-step hydrothermal method. These Se-CDs emitted red-wavelength fluorescence and were utilized to develop a sensitive fluorescence sensor for detecting microRNA-21 (miR-21). By incorporating deoxyribonuclease Ⅰ (DNase Ⅰ)-mediated signal amplification, the detection limit for miR -21 was improved from 78 to 6.8 nmol·L-1. Furthermore, we observed desirable inhibitory activity of the Se-CDs against Gram-negative bacteria of Escherichia coli (E. coli).
2024, 40(1): 182-196
doi: 10.11862/CJIC.20230375
Abstract:
Although thermodynamics tells us that solid-state reactions without solution will not stop until 100% completion, they may stop far before the exhaust of reactants because of the difficulty of mass transfer among the solid particles. To solve this problem, the author has publicized a novel technique called the less solvent solid-state reaction (LSR), which makes small parts of the solid reactants dissolve and react in a small amount of solvent, thus making the reaction proceed faster and more complete in a stirred reactor. Consequently, LSR could make some of the industrial processes greener. By using numerical calculating and charting of its Gibbs energies with respect to its extent of reaction, this paper proves that (ⅰ) an LSR is a combination of a reaction thermodynamically equivalent to a solution-free solid-state reaction in the middle and semi-solution reactions at both ends. Although the LSR does reach an equilibrium eventually, it goes much further to the 100% completion than the solution reaction; if the solvent is removed gradually at the ending period of the reaction, the LSR can be pushed to 100% completion; (ⅱ) for the consecutive reactions, it is possible to get the sole intermediate product by controlling the molar ratio of the reactants as its stoichiometric ratio; (ⅲ) it is possible to make an LSR with near-zero negative ΔrGmΘ 100% completed by using more solvent or using the solid products as seeds; (ⅳ) it is the dissolution speed of reactants, the speed of chemical reaction, and crystallization speed of products, rather than the solubilities of the substances that control the speed of an LSR. Measures for 100% completion and selection of LSRs of non-spontaneous or coexisting competitive reactions are also discussed.
Although thermodynamics tells us that solid-state reactions without solution will not stop until 100% completion, they may stop far before the exhaust of reactants because of the difficulty of mass transfer among the solid particles. To solve this problem, the author has publicized a novel technique called the less solvent solid-state reaction (LSR), which makes small parts of the solid reactants dissolve and react in a small amount of solvent, thus making the reaction proceed faster and more complete in a stirred reactor. Consequently, LSR could make some of the industrial processes greener. By using numerical calculating and charting of its Gibbs energies with respect to its extent of reaction, this paper proves that (ⅰ) an LSR is a combination of a reaction thermodynamically equivalent to a solution-free solid-state reaction in the middle and semi-solution reactions at both ends. Although the LSR does reach an equilibrium eventually, it goes much further to the 100% completion than the solution reaction; if the solvent is removed gradually at the ending period of the reaction, the LSR can be pushed to 100% completion; (ⅱ) for the consecutive reactions, it is possible to get the sole intermediate product by controlling the molar ratio of the reactants as its stoichiometric ratio; (ⅲ) it is possible to make an LSR with near-zero negative ΔrGmΘ 100% completed by using more solvent or using the solid products as seeds; (ⅳ) it is the dissolution speed of reactants, the speed of chemical reaction, and crystallization speed of products, rather than the solubilities of the substances that control the speed of an LSR. Measures for 100% completion and selection of LSRs of non-spontaneous or coexisting competitive reactions are also discussed.
2024, 40(1): 197-208
doi: 10.11862/CJIC.20230376
Abstract:
A series of ZnFe2O4/WO3 photocatalysts were constructed by loading ZnFe2O4 nanoparticles on the surface of WO 3 nanosheets, and their performance for photocatalytic CO2 reduction was studied. Under the conditions of no cocatalysts and sacrificial agents, the prepared ZnFe2O4/WO3 composite materials can catalyze the reaction between CO2 and water vapor. After illumination for 5 h, the yields of CO2 reduction products CO and CH4 of the optimal material were 7.87 and 4.88 μmol·g-1, respectively. Compared to its counterparts, the yields of CO and CH4 were improved. The increased photocatalytic activity of ZnFe2O4/WO3 is attributed to the formation of heterojunctions between ZnFe2O4 and WO3 as well as the S-scheme charge transfer mode of the photogenerated carriers, both of which are conducive to separation efficiency of photo-generated carriers and photocatalytic CO2 reduction activity.
A series of ZnFe2O4/WO3 photocatalysts were constructed by loading ZnFe2O4 nanoparticles on the surface of WO 3 nanosheets, and their performance for photocatalytic CO2 reduction was studied. Under the conditions of no cocatalysts and sacrificial agents, the prepared ZnFe2O4/WO3 composite materials can catalyze the reaction between CO2 and water vapor. After illumination for 5 h, the yields of CO2 reduction products CO and CH4 of the optimal material were 7.87 and 4.88 μmol·g-1, respectively. Compared to its counterparts, the yields of CO and CH4 were improved. The increased photocatalytic activity of ZnFe2O4/WO3 is attributed to the formation of heterojunctions between ZnFe2O4 and WO3 as well as the S-scheme charge transfer mode of the photogenerated carriers, both of which are conducive to separation efficiency of photo-generated carriers and photocatalytic CO2 reduction activity.
2024, 40(1): 209-220
doi: 10.11862/CJIC.20230377
Abstract:
A 2D Cd-based metal-organic framework with moderate coordination bond strength and adequate framework flexibility was obtained by self-assembly, namely {[Cd(HL)(BPY)0.5(H2O)]·2H2O}n (1), where H3L=4,4′,4″-(nitrilotris(methylene))tribenzoic acid, BPY=4,4′-bipyridine. Due to the unique structural features, under the stimulation of metal ions (Zn2+/Ni2+/Co2+), 1 gradually transforms into the MOF structures dominated by the corresponding metal ions (2, 3, and 4). During this process, with the exchanges of Cd2+→Zn2+, Cd2+→Ni2+, and Cd2+→Co2+, the free Cd2+ and L3- in the channel of 1 fuse with the backbone, leading to the channel space expansion and secondary building unit (SBU) transformation to form a tunable backbone. The photocatalytic CO2 reduction results show that the new structures obtained by ion exchange do not have a great improvement in catalytic efficiency, but have a great increase in product selectivity (3 demonstrated 100% CO selectivity).
A 2D Cd-based metal-organic framework with moderate coordination bond strength and adequate framework flexibility was obtained by self-assembly, namely {[Cd(HL)(BPY)0.5(H2O)]·2H2O}n (1), where H3L=4,4′,4″-(nitrilotris(methylene))tribenzoic acid, BPY=4,4′-bipyridine. Due to the unique structural features, under the stimulation of metal ions (Zn2+/Ni2+/Co2+), 1 gradually transforms into the MOF structures dominated by the corresponding metal ions (2, 3, and 4). During this process, with the exchanges of Cd2+→Zn2+, Cd2+→Ni2+, and Cd2+→Co2+, the free Cd2+ and L3- in the channel of 1 fuse with the backbone, leading to the channel space expansion and secondary building unit (SBU) transformation to form a tunable backbone. The photocatalytic CO2 reduction results show that the new structures obtained by ion exchange do not have a great improvement in catalytic efficiency, but have a great increase in product selectivity (3 demonstrated 100% CO selectivity).
2024, 40(1): 221-231
doi: 10.11862/CJIC.20230378
Abstract:
In this investigation, we have devised a highly proficient methodology for synthesizing covalent organic macrocycles. The reaction involving bisimidazolium salts H2-L1(BF4)2 (L1=A1, B1) with silver oxide resulted in the formation of binuclear silver metallacycles of the [Ag2(L1)2](BF4)2 (L1=A1, B1) classification. These metallacycles manifest olefinic appendages originating from two discrete dicarbene-bridged ligands arranged in pairs. Successive metal-carbene-templated ring-closing metathesis (RCM) precipitated the generation of two carbon-carbon double bonds connecting the two di-NHC ligands, thereby yielding cyclized binuclear silver metallacycles [Ag2(L2)](BF4)2 (L2=A2, B2). Subsequent removal of the metal ions led to the formation of covalent organic macrocycles H4-L2(BF4)4 (L2=A2, B2) with a substantial internal cavity. The dimensions and configuration of these polyimidazolium macrocycles can be facilely manipulated by adjusting the length and breadth of the bridging units in the ligands. Preliminary investigations indicate the potential applicability of this receptor in iodide sensing, detection, and recognition.
In this investigation, we have devised a highly proficient methodology for synthesizing covalent organic macrocycles. The reaction involving bisimidazolium salts H2-L1(BF4)2 (L1=A1, B1) with silver oxide resulted in the formation of binuclear silver metallacycles of the [Ag2(L1)2](BF4)2 (L1=A1, B1) classification. These metallacycles manifest olefinic appendages originating from two discrete dicarbene-bridged ligands arranged in pairs. Successive metal-carbene-templated ring-closing metathesis (RCM) precipitated the generation of two carbon-carbon double bonds connecting the two di-NHC ligands, thereby yielding cyclized binuclear silver metallacycles [Ag2(L2)](BF4)2 (L2=A2, B2). Subsequent removal of the metal ions led to the formation of covalent organic macrocycles H4-L2(BF4)4 (L2=A2, B2) with a substantial internal cavity. The dimensions and configuration of these polyimidazolium macrocycles can be facilely manipulated by adjusting the length and breadth of the bridging units in the ligands. Preliminary investigations indicate the potential applicability of this receptor in iodide sensing, detection, and recognition.
2024, 40(1): 232-246
doi: 10.11862/CJIC.20230381
Abstract:
Two pairs of chiral coordination compounds {[Co(D-hpg)(4,4′-bipy)(H2O)]Cl·H2O}n (1-D), {[Co(L-hpg)(4,4′-bipy)(H2O)]Cl·H2O}n (1-L), [Co(D-hpg)2(5,5′-BM-2,2′-bipy)]Cl·5.5H2O (2-D), and [Co(L-hpg)2(5,5′-BM-2,2′-bipy)] Cl·5.5H2O (2-L), where D-Hhpg=D-(-)-4-hydroxyphenylglycine, L-Hhpg=L-(+)-4-hydroxyphenylglycine, 4,4′-bipy= 4,4′-bipyridine, 5,5′-BM-2,2′-bipy=5,5′-dimethyl-2,2′-bipyridine, have been successfully synthesized. Their structures were determined by single-crystal X-ray diffraction analysis and characterized by elemental analysis, X-ray photoelectron spectra, infrared spectroscopy, solid-state circular dichroism spectra, thermogravimetric analysis, powder X-ray diffraction, and electrochemical methods. Compounds 1-D and 1-L feature 2D (4, 4) rectangular grid networks that consist of left-or right-handed helical chains. Compounds 2-D and 2-L exhibit 0D molecule structures, and further 1D supramolecular double chains are formed by hydrogen bonding. The differences in the structures of these compounds are attributed to the influence of ancillary N-donor ligands and the coordination modes of Hhpg. Moreover, compound 1-D displays electrochemically reversible redox behavior, and serves as an electrochemical sensor for efficiently detecting histidine (His) enantiomers and quantitatively determining the enantiomeric excess in the His mixture.
Two pairs of chiral coordination compounds {[Co(D-hpg)(4,4′-bipy)(H2O)]Cl·H2O}n (1-D), {[Co(L-hpg)(4,4′-bipy)(H2O)]Cl·H2O}n (1-L), [Co(D-hpg)2(5,5′-BM-2,2′-bipy)]Cl·5.5H2O (2-D), and [Co(L-hpg)2(5,5′-BM-2,2′-bipy)] Cl·5.5H2O (2-L), where D-Hhpg=D-(-)-4-hydroxyphenylglycine, L-Hhpg=L-(+)-4-hydroxyphenylglycine, 4,4′-bipy= 4,4′-bipyridine, 5,5′-BM-2,2′-bipy=5,5′-dimethyl-2,2′-bipyridine, have been successfully synthesized. Their structures were determined by single-crystal X-ray diffraction analysis and characterized by elemental analysis, X-ray photoelectron spectra, infrared spectroscopy, solid-state circular dichroism spectra, thermogravimetric analysis, powder X-ray diffraction, and electrochemical methods. Compounds 1-D and 1-L feature 2D (4, 4) rectangular grid networks that consist of left-or right-handed helical chains. Compounds 2-D and 2-L exhibit 0D molecule structures, and further 1D supramolecular double chains are formed by hydrogen bonding. The differences in the structures of these compounds are attributed to the influence of ancillary N-donor ligands and the coordination modes of Hhpg. Moreover, compound 1-D displays electrochemically reversible redox behavior, and serves as an electrochemical sensor for efficiently detecting histidine (His) enantiomers and quantitatively determining the enantiomeric excess in the His mixture.
2024, 40(1): 247-255
doi: 10.11862/CJIC.20230386
Abstract:
Two mixed organic cationic hybrid formate salts, (CH(NH2)2)[RE(HCOO)4] (RE=Y, Er), have been obtained by in situ solvothermal synthesis. The two materials are isostructural (chiral space group C2221) and feature interesting perovskite-like structures. Photophysical studies including linear and nonlinear optical characteristics were performed. (CH(NH2)2)[Y(HCOO)4] and (CH(NH2)2)[Er(HCOO)4] exhibited wide optical bandgaps of 5.59 and 5.61 eV, corresponding to the UV absorption edges of 222 and 221 nm, respectively. Powder second harmonic generation (SHG) measurements demonstrate that the SHG effects of (CH(NH2)2)[Y(HCOO)4] and (CH(NH2)2)[Er(HCOO)4] were 0.32 and 0.37 times that of benchmark KH2PO4 (KDP), respectively. The birefringences were measured to be 0.013 and 0.015 for (CH(NH2)2)[Y(HCOO)4] and (CH(NH2)2)[Er(HCOO)4], respectively. First-principles studies show that two π -conjugated (CH(NH2)2)+ and HCOO- groups are the main contributors to the optical properties.
Two mixed organic cationic hybrid formate salts, (CH(NH2)2)[RE(HCOO)4] (RE=Y, Er), have been obtained by in situ solvothermal synthesis. The two materials are isostructural (chiral space group C2221) and feature interesting perovskite-like structures. Photophysical studies including linear and nonlinear optical characteristics were performed. (CH(NH2)2)[Y(HCOO)4] and (CH(NH2)2)[Er(HCOO)4] exhibited wide optical bandgaps of 5.59 and 5.61 eV, corresponding to the UV absorption edges of 222 and 221 nm, respectively. Powder second harmonic generation (SHG) measurements demonstrate that the SHG effects of (CH(NH2)2)[Y(HCOO)4] and (CH(NH2)2)[Er(HCOO)4] were 0.32 and 0.37 times that of benchmark KH2PO4 (KDP), respectively. The birefringences were measured to be 0.013 and 0.015 for (CH(NH2)2)[Y(HCOO)4] and (CH(NH2)2)[Er(HCOO)4], respectively. First-principles studies show that two π -conjugated (CH(NH2)2)+ and HCOO- groups are the main contributors to the optical properties.
2024, 40(1): 256-262
doi: 10.11862/CJIC.20230390
Abstract:
Monodispersed MoS2 core-shell spheres were produced by annealing precursor MoS2 core-shell superspheres at 900 ℃ in Ar. Simultaneously, O-doping amount (atomic fraction) can be tuned from 23.1% of precursor to 17.6%, 10.8%, 5.5%, and 6.2% of as-prepared materials by regulating the heating rate of 20, 10, 5, and 2 ℃·min-1, respectively. The lower rate results in a lower amount of O doped onto MoS2 core-shell spheres. Based on the special quasi-molecular superlattices of precursors, an in-situ anion exchange reaction mechanism was proposed to understand the dynamical modulation of O-doping. The study on the electrochemical properties of the materials demonstrates that their electrochemical performance in splitting water can be improved by tuning the O-doping amount.
Monodispersed MoS2 core-shell spheres were produced by annealing precursor MoS2 core-shell superspheres at 900 ℃ in Ar. Simultaneously, O-doping amount (atomic fraction) can be tuned from 23.1% of precursor to 17.6%, 10.8%, 5.5%, and 6.2% of as-prepared materials by regulating the heating rate of 20, 10, 5, and 2 ℃·min-1, respectively. The lower rate results in a lower amount of O doped onto MoS2 core-shell spheres. Based on the special quasi-molecular superlattices of precursors, an in-situ anion exchange reaction mechanism was proposed to understand the dynamical modulation of O-doping. The study on the electrochemical properties of the materials demonstrates that their electrochemical performance in splitting water can be improved by tuning the O-doping amount.
2024, 40(1): 263-269
doi: 10.11862/CJIC.20230396
Abstract:
Three complexes with different structures, namely {[Cu6(H2tba)6]·2DMF·xSolvent} (1), {[Sc(H2tba)3(DMF)]·2DMF}n (2), and {[Fe(H2tba)2(H2O)2]·2DMF}n (3) (DMF=N, N-dimethylformamide), were obtained through diffusion reactions using Cu(ClO4)2·6H2O, Sc(ClO4)3·6H2O, and Fe(ClO4)3·9H2O as metal salts, respectively, and 2-thiobarbituric acid (H3tba) as ligand. Complexes 1-3 were further characterized by FTIR, elemental analysis, TGA, and powder X-ray diffraction techniques. Single-crystal X-ray diffraction analysis reveals that complex 1 is a hexa-copper cluster with a trigonal antiprism structure, complex 2 is a 2D sheet structure, and complex 3 is a 3D network structure. Complex 1 exhibited strong luminescent emission spectra at 735 nm with an excitation peak at 390 nm.
Three complexes with different structures, namely {[Cu6(H2tba)6]·2DMF·xSolvent} (1), {[Sc(H2tba)3(DMF)]·2DMF}n (2), and {[Fe(H2tba)2(H2O)2]·2DMF}n (3) (DMF=N, N-dimethylformamide), were obtained through diffusion reactions using Cu(ClO4)2·6H2O, Sc(ClO4)3·6H2O, and Fe(ClO4)3·9H2O as metal salts, respectively, and 2-thiobarbituric acid (H3tba) as ligand. Complexes 1-3 were further characterized by FTIR, elemental analysis, TGA, and powder X-ray diffraction techniques. Single-crystal X-ray diffraction analysis reveals that complex 1 is a hexa-copper cluster with a trigonal antiprism structure, complex 2 is a 2D sheet structure, and complex 3 is a 3D network structure. Complex 1 exhibited strong luminescent emission spectra at 735 nm with an excitation peak at 390 nm.
2024, 40(1): 270-280
doi: 10.11862/CJIC.20230409
Abstract:
Combining photoreactive anthracene moieties with lanthanide ions, we obtained three new isostructural mononuclear compounds with the formulas Ln(SCN)2(NO3)(depma)2(4-hpy)2 (Ln=Er (1Er), Nd (2Nd), Y (3Y), where depma is 9-diethylphosphonomethylanthracene, and their single molecule magnet and photodimerization behaviors were studied. All contain face-to-face π-π interacted anthracene groups that meet the Schmidt rule for a [4+4] photocycloaddition reaction. 1Er and 2Nd show characteristic near-infrared (NIR) luminescence owing to the efficient energy transfer from the ligand to the lanthanide ion, while 3Y displays excimer emission in the visible region. As a result, only 3Y underwent photocycloaddition reaction under 395 nm UV light irradiation to form [Y(SCN)2(NO3)(depma2)(4-hpy)2]n (3Y-UV). Magnetic studies revealed a field-induced slow relaxation of the magnetization at low temperatures for compounds 1Er and 2Nd, and the dominant relaxation process was the Raman process for 2Nd. After doping ErⅢ or NdⅢ into 3Y, we constructed the isomorphic samples Ln0.1Y0.9(SCN)2(NO3)(depma)2(4-hpy)2 (Ln=Er (1Er@Y), Nd (2Nd@Y)). Interestingly, the diluted samples exhibited an incomplete photocycloaddition reaction, accompanied by changes in their luminescence colors from yellow-green to blue. Furthermore, partial photocycloaddition of anthracene groups in 2Nd@Y led to a slight change in the magnetic dynamics, manifested by an increase in the n value of the Raman process from 3.8 (2Nd@Y) to 5.2 (2Nd@Y-UV) which is attributed to the change in its phonon structure.
Combining photoreactive anthracene moieties with lanthanide ions, we obtained three new isostructural mononuclear compounds with the formulas Ln(SCN)2(NO3)(depma)2(4-hpy)2 (Ln=Er (1Er), Nd (2Nd), Y (3Y), where depma is 9-diethylphosphonomethylanthracene, and their single molecule magnet and photodimerization behaviors were studied. All contain face-to-face π-π interacted anthracene groups that meet the Schmidt rule for a [4+4] photocycloaddition reaction. 1Er and 2Nd show characteristic near-infrared (NIR) luminescence owing to the efficient energy transfer from the ligand to the lanthanide ion, while 3Y displays excimer emission in the visible region. As a result, only 3Y underwent photocycloaddition reaction under 395 nm UV light irradiation to form [Y(SCN)2(NO3)(depma2)(4-hpy)2]n (3Y-UV). Magnetic studies revealed a field-induced slow relaxation of the magnetization at low temperatures for compounds 1Er and 2Nd, and the dominant relaxation process was the Raman process for 2Nd. After doping ErⅢ or NdⅢ into 3Y, we constructed the isomorphic samples Ln0.1Y0.9(SCN)2(NO3)(depma)2(4-hpy)2 (Ln=Er (1Er@Y), Nd (2Nd@Y)). Interestingly, the diluted samples exhibited an incomplete photocycloaddition reaction, accompanied by changes in their luminescence colors from yellow-green to blue. Furthermore, partial photocycloaddition of anthracene groups in 2Nd@Y led to a slight change in the magnetic dynamics, manifested by an increase in the n value of the Raman process from 3.8 (2Nd@Y) to 5.2 (2Nd@Y-UV) which is attributed to the change in its phonon structure.
2024, 40(1): 281-288
doi: 10.11862/CJIC.20230429
Abstract:
A rare earth metal formate, (C(NH2)3)[Er(HCOO)4], was prepared via an evaporation method. Benefiting from its non-centrosymmetric structure, optical property studies reveal that (C(NH2)3)[Er(HCOO)4] possessed a wide optical bandgap of 4.76 eV, moderate birefringence (0.066@546 nm), second harmonic generation (SHG) response (0.20 times that of KH2PO4 (KDP)), and phase-matchable capabilities at 1 064 nm. Theoretical calculations and crystal structure analysis revealed that the optical properties can be attributed to the synergy effects of the (C(NH2)3)+, [ErO8], and HCOO- units.
A rare earth metal formate, (C(NH2)3)[Er(HCOO)4], was prepared via an evaporation method. Benefiting from its non-centrosymmetric structure, optical property studies reveal that (C(NH2)3)[Er(HCOO)4] possessed a wide optical bandgap of 4.76 eV, moderate birefringence (0.066@546 nm), second harmonic generation (SHG) response (0.20 times that of KH2PO4 (KDP)), and phase-matchable capabilities at 1 064 nm. Theoretical calculations and crystal structure analysis revealed that the optical properties can be attributed to the synergy effects of the (C(NH2)3)+, [ErO8], and HCOO- units.
