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2024 Volume 40 Issue 5
2024, 40(5): 849-856
doi: 10.11862/CJIC.20230479
Abstract:
Three zinc coordination polymers, {[Zn2(bipmo)2(ipa)2]·3H2O}n (1), {[Zn(bipmo)(5-OH-ipa)]·DMA·H2O}n (2), and {[Zn(bipmo)(5-Me-ipa)]·H2O}n (3), where bipmo=bis(4-(1H-imidazol-1-yl)phenyl)methanone, H2ipa=isophthalic acid, 5-OH-ipaH2=5-hydroxyisophthalic acid, 5-Me-ipaH2=5-methylisophthalic acid, were synthesized under solvothermal conditions. These complexes have been characterized by elemental analyses, IR spectra, single-crystal X-ray diffraction, etc. Complex 1 shows a 2D 2-fold interpenetrating {44·62} network. Complex 2 displays a 2D uninodal framework with the {65·8} topology. Complex 3 reveals a 2D layer structure with {63} topology. The results indicate that the presence of a 5-substituted group in the isophthalate exerts a significant influence on the formation of the final structures. The luminescent properties of the complexes in the solid state have also been studied.
Three zinc coordination polymers, {[Zn2(bipmo)2(ipa)2]·3H2O}n (1), {[Zn(bipmo)(5-OH-ipa)]·DMA·H2O}n (2), and {[Zn(bipmo)(5-Me-ipa)]·H2O}n (3), where bipmo=bis(4-(1H-imidazol-1-yl)phenyl)methanone, H2ipa=isophthalic acid, 5-OH-ipaH2=5-hydroxyisophthalic acid, 5-Me-ipaH2=5-methylisophthalic acid, were synthesized under solvothermal conditions. These complexes have been characterized by elemental analyses, IR spectra, single-crystal X-ray diffraction, etc. Complex 1 shows a 2D 2-fold interpenetrating {44·62} network. Complex 2 displays a 2D uninodal framework with the {65·8} topology. Complex 3 reveals a 2D layer structure with {63} topology. The results indicate that the presence of a 5-substituted group in the isophthalate exerts a significant influence on the formation of the final structures. The luminescent properties of the complexes in the solid state have also been studied.
2024, 40(5): 972-978
doi: 10.11862/CJIC.20230411
Abstract:
Employing the reaction of chiral nitronyl nitroxide radical and rare-earth ions, two 2p-4f hetero-spin meso complexes [Ln(hfac)3((R)-MePP-Ph-NIT)]2, where Ln=Eu (1) and Dy (2), hfac=hexafluoroacetylacetone; (R)-MePP-Ph-NIT=2-(4-((R)-tert-butyl-2-methylpiperazine-1-carboxylate)phenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, have been assembled. In both complexes, two chiral radicals ligate to two Ln(Ⅲ) ions to produce a cyclic dinuclear structure. Complex 1 shows the characteristic fluorescence emission of the Eu(Ⅲ) ion. In complex 2, the frequency-dependent out-of-phase susceptibility signals connected with magnetic relaxation confirm single-molecule magnet (SMM) behavior.
Employing the reaction of chiral nitronyl nitroxide radical and rare-earth ions, two 2p-4f hetero-spin meso complexes [Ln(hfac)3((R)-MePP-Ph-NIT)]2, where Ln=Eu (1) and Dy (2), hfac=hexafluoroacetylacetone; (R)-MePP-Ph-NIT=2-(4-((R)-tert-butyl-2-methylpiperazine-1-carboxylate)phenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, have been assembled. In both complexes, two chiral radicals ligate to two Ln(Ⅲ) ions to produce a cyclic dinuclear structure. Complex 1 shows the characteristic fluorescence emission of the Eu(Ⅲ) ion. In complex 2, the frequency-dependent out-of-phase susceptibility signals connected with magnetic relaxation confirm single-molecule magnet (SMM) behavior.
2024, 40(5): 979-990
doi: 10.11862/CJIC.20240008
Abstract:
A novel Cu-based composite with unique three-dimensional (3D) nanoflower-like morphology and mesoporous structure (abbreviated as Cu-NF) was developed, using zeolitic imidazolate framework-67 (ZIF-67) as precursor via facile Cu ion etching, followed by low-temperature calcination strategy. The mass ratio of Cu2+ to ZIF-67 played a key role in morphology control. Additionally, low-temperature calcination changed the chemical components of the active sites and improved the porosity for mass transportation with the original morphology preserved. Sample Cu-NF-300, calcined at 300 ℃ displayed the best oxygen evolution reaction (OER) performance among all the samples, with a small overpotential of 347 mV in 1.0 mol·L-1 KOH and a low Tafel slope of 93 mV·dec-1 for OER. Significant improvement in the electrochemical activity is attributed to the 3D superstructure and low-temperature calcination activation, which offer a simple synthetic strategy for the fabrication of Cu-based electrocatalysts for OER.
A novel Cu-based composite with unique three-dimensional (3D) nanoflower-like morphology and mesoporous structure (abbreviated as Cu-NF) was developed, using zeolitic imidazolate framework-67 (ZIF-67) as precursor via facile Cu ion etching, followed by low-temperature calcination strategy. The mass ratio of Cu2+ to ZIF-67 played a key role in morphology control. Additionally, low-temperature calcination changed the chemical components of the active sites and improved the porosity for mass transportation with the original morphology preserved. Sample Cu-NF-300, calcined at 300 ℃ displayed the best oxygen evolution reaction (OER) performance among all the samples, with a small overpotential of 347 mV in 1.0 mol·L-1 KOH and a low Tafel slope of 93 mV·dec-1 for OER. Significant improvement in the electrochemical activity is attributed to the 3D superstructure and low-temperature calcination activation, which offer a simple synthetic strategy for the fabrication of Cu-based electrocatalysts for OER.
2024, 40(5): 991-1004
doi: 10.11862/CJIC.20230458
Abstract:
Five inorganic monoiron(Ⅱ) carbonyl salts 1-5, fac-M[Fe(CO)3I3]n (Mn+=Na+ (1), K+ (2), Mg2+ (3), Ca2+ (4), NH4+ (5)) were prepared from the reactions of cis-[Fe(CO)4I2] precursor with the iodo salts (MIn), and developed as CO-releasing molecules (CORMs) for CO therapy of cancer. The decomposition of salts 1-5 with CO-release in DMSO, D2O, saline, and phosphonate buffer solution was investigated by the Fourier transform infrared (FTIR) spectroscopic monitoring. The corresponding kinetics for the decomposing of these salts were estimated by abiding by a first-order model. Cytotoxicity of the five salts was assessed on a bladder cancer cell line (RT112) by the methyl thiazolyl tetrazolium (MTT) assays for 24 h, with the half maximal inhibitory concentration (IC50) values of 25-43 μmol·L-1. Notably, varying a counter ion of fac-[Fe(CO)3I3]- anion from an organic aminium to an inorganic cation unambiguously affects its stability and thus the cytotoxicity. Moreover, a mechanistic probing into the cytotoxicity of fac-[Fe(CO)3I3]- anion was paved. Interestingly, not only the produced iodine radicals but also the gaseous CO from the decomposition contributed to its cytotoxicity. Particularly, it was found that, with the treatment of the anion, the reactive oxygen species (ROS) level in the mitochondria significantly enhanced, and the mitochondria-related protein expression of Parkin was extremely upregulated. The ferroptosis inhibitor assays of Ferrostatin‑1 and Liproxstatin-1 confirmed that these complexes evoked a ferroptosis-involved pathway to contribute to their cytotoxicity. Therefore, a mechanistic understanding of the cytotoxicity of fac-[Fe(CO)3I3]- anion is proposed, which is stimulated by the decomposing of the anion, and thus manufactures the mitochondria-relevant activities such as fission, energy metabolism, and mitophagy, and evokes a pathway of ferroptosis, to lead severe cellular damage even death.
Five inorganic monoiron(Ⅱ) carbonyl salts 1-5, fac-M[Fe(CO)3I3]n (Mn+=Na+ (1), K+ (2), Mg2+ (3), Ca2+ (4), NH4+ (5)) were prepared from the reactions of cis-[Fe(CO)4I2] precursor with the iodo salts (MIn), and developed as CO-releasing molecules (CORMs) for CO therapy of cancer. The decomposition of salts 1-5 with CO-release in DMSO, D2O, saline, and phosphonate buffer solution was investigated by the Fourier transform infrared (FTIR) spectroscopic monitoring. The corresponding kinetics for the decomposing of these salts were estimated by abiding by a first-order model. Cytotoxicity of the five salts was assessed on a bladder cancer cell line (RT112) by the methyl thiazolyl tetrazolium (MTT) assays for 24 h, with the half maximal inhibitory concentration (IC50) values of 25-43 μmol·L-1. Notably, varying a counter ion of fac-[Fe(CO)3I3]- anion from an organic aminium to an inorganic cation unambiguously affects its stability and thus the cytotoxicity. Moreover, a mechanistic probing into the cytotoxicity of fac-[Fe(CO)3I3]- anion was paved. Interestingly, not only the produced iodine radicals but also the gaseous CO from the decomposition contributed to its cytotoxicity. Particularly, it was found that, with the treatment of the anion, the reactive oxygen species (ROS) level in the mitochondria significantly enhanced, and the mitochondria-related protein expression of Parkin was extremely upregulated. The ferroptosis inhibitor assays of Ferrostatin‑1 and Liproxstatin-1 confirmed that these complexes evoked a ferroptosis-involved pathway to contribute to their cytotoxicity. Therefore, a mechanistic understanding of the cytotoxicity of fac-[Fe(CO)3I3]- anion is proposed, which is stimulated by the decomposing of the anion, and thus manufactures the mitochondria-relevant activities such as fission, energy metabolism, and mitophagy, and evokes a pathway of ferroptosis, to lead severe cellular damage even death.
2024, 40(5): 1005-1014
doi: 10.11862/CJIC.20230444
Abstract:
Herein, the positively charged two-dimensional (2D) porous silica (PSN+) nanosheet was obtained by modifying the 2D silica obtained from acid-etched 2D vermiculite, and then the PSN+ was used as the filler of polyethylene oxide (PEO)-based solid polymer electrolytes (SPEs). Given the abundant positive charges, PSN+ effectively binds with the anions dissociated from lithium salts, thereby promoting lithium-ion transport and achieving a decent lithium-ion transference number. At 50 ℃, the PSN+-based SPEs demonstrated a higher ionic conductivity of 7.5×10-5 S·cm-1, lithium-ion transference number of 0.30, and a stable voltage window of 4.41 V. Consequently, the as-assembled LiFePO4||Li batteries delivered excellent initial discharge specific capacity of 155.7 mAh·g-1 at 0.2C with 97.1% capacity retention after 100 cycles at 50 ℃.
Herein, the positively charged two-dimensional (2D) porous silica (PSN+) nanosheet was obtained by modifying the 2D silica obtained from acid-etched 2D vermiculite, and then the PSN+ was used as the filler of polyethylene oxide (PEO)-based solid polymer electrolytes (SPEs). Given the abundant positive charges, PSN+ effectively binds with the anions dissociated from lithium salts, thereby promoting lithium-ion transport and achieving a decent lithium-ion transference number. At 50 ℃, the PSN+-based SPEs demonstrated a higher ionic conductivity of 7.5×10-5 S·cm-1, lithium-ion transference number of 0.30, and a stable voltage window of 4.41 V. Consequently, the as-assembled LiFePO4||Li batteries delivered excellent initial discharge specific capacity of 155.7 mAh·g-1 at 0.2C with 97.1% capacity retention after 100 cycles at 50 ℃.
2024, 40(5): 1015-1024
doi: 10.11862/CJIC.20230433
Abstract:
Graphitic carbon nitride (CN)-based materials were synthesized using melamine, urea, guanidine carbonate, and thiourea as precursors via pyrolysis. The synthesized materials underwent comprehensive characterization employing techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption-desorption test. These materials were evaluated for their performance as cathodes with platinum sheet electrodes as anodes in the selective electrocatalytic reduction of Sn(Ⅳ) in an acid solution. During the reduction of Sn(Ⅳ) to Sn(Ⅱ), Sn(Ⅱ) can also be reduced to Sn due to the similar reduction potentials of Sn(Ⅱ) and Sn(Ⅳ). The deposition of Sn on the cathode diminishes the electrode conductivity efficiency. Therefore, the electrode material must fulfill the dual requirements of reducing Sn(Ⅳ) to Sn(Ⅱ) while preventing the reduction of Sn(Ⅱ) to Sn. In comparison to conventional cathode materials such as copper plates, graphite plates, ruthenium iridium titanium plates, and platinum plates, the CN demonstrated superior performance in the selective electrocatalytic reduction of Sn(Ⅳ) in an acidic solution. In addition, CN exhibited a lower potential in a dual-electrode electrolytic cell and maintained stability under acidic conditions, enabling the selective reduction of Sn(Ⅳ) to Sn(Ⅱ).
Graphitic carbon nitride (CN)-based materials were synthesized using melamine, urea, guanidine carbonate, and thiourea as precursors via pyrolysis. The synthesized materials underwent comprehensive characterization employing techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption-desorption test. These materials were evaluated for their performance as cathodes with platinum sheet electrodes as anodes in the selective electrocatalytic reduction of Sn(Ⅳ) in an acid solution. During the reduction of Sn(Ⅳ) to Sn(Ⅱ), Sn(Ⅱ) can also be reduced to Sn due to the similar reduction potentials of Sn(Ⅱ) and Sn(Ⅳ). The deposition of Sn on the cathode diminishes the electrode conductivity efficiency. Therefore, the electrode material must fulfill the dual requirements of reducing Sn(Ⅳ) to Sn(Ⅱ) while preventing the reduction of Sn(Ⅱ) to Sn. In comparison to conventional cathode materials such as copper plates, graphite plates, ruthenium iridium titanium plates, and platinum plates, the CN demonstrated superior performance in the selective electrocatalytic reduction of Sn(Ⅳ) in an acidic solution. In addition, CN exhibited a lower potential in a dual-electrode electrolytic cell and maintained stability under acidic conditions, enabling the selective reduction of Sn(Ⅳ) to Sn(Ⅱ).
2024, 40(5): 1025-1032
doi: 10.11862/CJIC.20230416
Abstract:
A dual-targeting melanin nanoparticle (MNP-TPP-HA) was constructed by grafting the carboxyl groups of hyaluronic acid (HA) and (4-carboxybutyl) triphenylphosphonium bromide (TPP) onto the surface of polyethylene glycol-amino (PEG-NH2) modified MNP based on 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and N-hydroxy succinimide (NHS) reaction, endowing melanin with the ability of dual active targeting. The fluorescence imaging of in vitro three-dimensional (3D) tumor models and in vivo photoacoustic imaging (PAI) all reveal the excellent target penetration ability of MNP-TPP-HA.
A dual-targeting melanin nanoparticle (MNP-TPP-HA) was constructed by grafting the carboxyl groups of hyaluronic acid (HA) and (4-carboxybutyl) triphenylphosphonium bromide (TPP) onto the surface of polyethylene glycol-amino (PEG-NH2) modified MNP based on 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and N-hydroxy succinimide (NHS) reaction, endowing melanin with the ability of dual active targeting. The fluorescence imaging of in vitro three-dimensional (3D) tumor models and in vivo photoacoustic imaging (PAI) all reveal the excellent target penetration ability of MNP-TPP-HA.
2024, 40(5): 857-866
doi: 10.11862/CJIC.20230462
Abstract:
BaTiO3 was synthesized at low-temperatures based on the starch gelatinization mechanism. The morphology and phase structure of as-synthesized samples were characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), UV visible (UV-Vis) absorption spectra, and X-ray photoelectron spectroscopy (XPS). The piezocatalytic performance of BaTiO3 was tested targeting a series of typical dyes for degradation. The results showed that tetragonal BaTiO3 powder was obtained at a calcination temperature of 600 ℃, and the crystallinity gradually increased with the increase in temperature. Cubic-like BaTiO3 with uniform size distribution was synthesized at a calcination temperature of 700 ℃; The degradation of rhodamine B (RhB), Congo red (CR), and methyl orange (MO) dyes by BaTiO3 all showed good performance, with reaction rate constants of 1.090×10-2, 1.113×10-2, and 1.084×10-2 min-1, respectively. Furthermore, the mechanism of piezocatalysis reveals that the hole (h+) and superoxide radicals (·O2-) are the main reactive species in the degradation process by targeting the degradation of CR.
BaTiO3 was synthesized at low-temperatures based on the starch gelatinization mechanism. The morphology and phase structure of as-synthesized samples were characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), UV visible (UV-Vis) absorption spectra, and X-ray photoelectron spectroscopy (XPS). The piezocatalytic performance of BaTiO3 was tested targeting a series of typical dyes for degradation. The results showed that tetragonal BaTiO3 powder was obtained at a calcination temperature of 600 ℃, and the crystallinity gradually increased with the increase in temperature. Cubic-like BaTiO3 with uniform size distribution was synthesized at a calcination temperature of 700 ℃; The degradation of rhodamine B (RhB), Congo red (CR), and methyl orange (MO) dyes by BaTiO3 all showed good performance, with reaction rate constants of 1.090×10-2, 1.113×10-2, and 1.084×10-2 min-1, respectively. Furthermore, the mechanism of piezocatalysis reveals that the hole (h+) and superoxide radicals (·O2-) are the main reactive species in the degradation process by targeting the degradation of CR.
2024, 40(5): 867-876
doi: 10.11862/CJIC.20230441
Abstract:
A simple, efficient, and scalable one-step high-temperature nitriding method was used to convert titanium dioxide into titanium nitride, meanwhile, the continuous three-dimensional porous network with good electrical conductivity and high porosity was formed under high-temperature sintering. As a highly efficient sulfur host, the continuous three-dimensional porous titanium nitride network not only effectively increases the electron transport path, enhances the electron transfer, and promotes the ion migration, but also strongly restricts the shuttle effect of lithium polysulfides from both physical limiting and chemisorption, and effectively increases the sulfur loading. The as-prepared sulfur cathode with high conductivity, high catalytic activity, and high sulfur loading shows high discharge capacity and excellent cyclic stability.
A simple, efficient, and scalable one-step high-temperature nitriding method was used to convert titanium dioxide into titanium nitride, meanwhile, the continuous three-dimensional porous network with good electrical conductivity and high porosity was formed under high-temperature sintering. As a highly efficient sulfur host, the continuous three-dimensional porous titanium nitride network not only effectively increases the electron transport path, enhances the electron transfer, and promotes the ion migration, but also strongly restricts the shuttle effect of lithium polysulfides from both physical limiting and chemisorption, and effectively increases the sulfur loading. The as-prepared sulfur cathode with high conductivity, high catalytic activity, and high sulfur loading shows high discharge capacity and excellent cyclic stability.
2024, 40(5): 877-884
doi: 10.11862/CJIC.20230440
Abstract:
Fluorescence molecular detection exhibits limited development in detection applications due to generally low sensitivity and narrow detection range. The heavily doped semiconductor nanostructures Cu2-xS with surface plasmon resonance effect and typical rare-earth-doped upconversion luminescent nanoparticles NaYF4∶Yb, Er were prepared, and further Cu2-xS/NaYF4∶Yb, Er film substrates were obtained by three-phase interfacial self-assembly method. Combined with finite element method simulations, the local electric field distributions around Cu2-xS were calculated for different placement situations. The plasmon-coupling effect generated between Cu2-xS nanodisks was investigated on the upconversion luminescence performance and the Raman signals. Based on the intense upconversion luminescence caused by the excellent synergetic localized surface plasmon resonance effect, a dual detection method of qualitative before quantitative detection of Rhodamine B using surface-enhanced Raman scattering signal monitoring and fluorescence sensing was established. The results show that the coupling of the Cu2-xS plasmonic layer with the NaYF4∶Yb, Er luminescent layer not only enables three orders of magnitude improvement of upconversion emission, but also achieves the detection limit of 10-7 mol·L-1 for molecular detection and obtains a broad linear response from 10-3 to 10-7 mol·L-1, and finally realizes the qualitative and quantitative bifunctionality of high-sensitivity accurate detection.
Fluorescence molecular detection exhibits limited development in detection applications due to generally low sensitivity and narrow detection range. The heavily doped semiconductor nanostructures Cu2-xS with surface plasmon resonance effect and typical rare-earth-doped upconversion luminescent nanoparticles NaYF4∶Yb, Er were prepared, and further Cu2-xS/NaYF4∶Yb, Er film substrates were obtained by three-phase interfacial self-assembly method. Combined with finite element method simulations, the local electric field distributions around Cu2-xS were calculated for different placement situations. The plasmon-coupling effect generated between Cu2-xS nanodisks was investigated on the upconversion luminescence performance and the Raman signals. Based on the intense upconversion luminescence caused by the excellent synergetic localized surface plasmon resonance effect, a dual detection method of qualitative before quantitative detection of Rhodamine B using surface-enhanced Raman scattering signal monitoring and fluorescence sensing was established. The results show that the coupling of the Cu2-xS plasmonic layer with the NaYF4∶Yb, Er luminescent layer not only enables three orders of magnitude improvement of upconversion emission, but also achieves the detection limit of 10-7 mol·L-1 for molecular detection and obtains a broad linear response from 10-3 to 10-7 mol·L-1, and finally realizes the qualitative and quantitative bifunctionality of high-sensitivity accurate detection.
2024, 40(5): 885-894
doi: 10.11862/CJIC.20230435
Abstract:
A series of Cu2O/Bi2MoO6 photocatalysts with Z-type heterojunction were prepared by hydrothermal method. The morphology, structural properties, and photoelectrochemical properties of the catalyst were characterized by scanning electron microscopy, powder X-ray diffraction, IR spectroscopy, UV-Vis absorption spectroscopy, etc. The photocatalytic properties were investigated by tetracycline (TC) degradation. The experimental results showed that the photocatalytic performance of the composite was enhanced by adding Cu2O. Among them, 20% Cu2O/Bi2MoO6 composite (The mass ratio of Cu2O and Bi2MoO6 was 20%.) exhibited the best degradation efficiency and 95% of TC was degraded within 100 min. The possible mechanism of photocatalytic degradation of TC by the Cu2O/Bi2MoO6 composite was analyzed through free radical capture experiments and band structure analysis. The absorption of visible light is enhanced by the synergistic effect between Cu2O and Bi2MoO6 and the transfer pathway of electrons is changed by the constructed Z-type heterojunction. Thus, the separation efficiency of the electron-hole is improved and the photocatalytic activity is enhanced significantly.
A series of Cu2O/Bi2MoO6 photocatalysts with Z-type heterojunction were prepared by hydrothermal method. The morphology, structural properties, and photoelectrochemical properties of the catalyst were characterized by scanning electron microscopy, powder X-ray diffraction, IR spectroscopy, UV-Vis absorption spectroscopy, etc. The photocatalytic properties were investigated by tetracycline (TC) degradation. The experimental results showed that the photocatalytic performance of the composite was enhanced by adding Cu2O. Among them, 20% Cu2O/Bi2MoO6 composite (The mass ratio of Cu2O and Bi2MoO6 was 20%.) exhibited the best degradation efficiency and 95% of TC was degraded within 100 min. The possible mechanism of photocatalytic degradation of TC by the Cu2O/Bi2MoO6 composite was analyzed through free radical capture experiments and band structure analysis. The absorption of visible light is enhanced by the synergistic effect between Cu2O and Bi2MoO6 and the transfer pathway of electrons is changed by the constructed Z-type heterojunction. Thus, the separation efficiency of the electron-hole is improved and the photocatalytic activity is enhanced significantly.
2024, 40(5): 895-906
doi: 10.11862/CJIC.20230434
Abstract:
A Z-scheme heterojunction photocatalyst Ag - Cu2 O/BiVO4 was successfully constructed with effective charge carrier separation/transfer by uniformly encapsulating Cu2O nanospheres and Ag nanoparticles on the surface of decahedral BiVO4 using a simple chemical reduction deposition strategy. The photo-reduction of carbon dioxide reaction result indicated that the as - prepared Ag - Cu2O/BiVO4 heterostructure exhibited excellent activity of photo-reduction CO2 with the CO yield of 5.37 μmol·g-1·h-1, about 35.8 times and 6.25 times of original BiVO4 and Cu2O, respectively. Ag-Cu2O/BiVO4 was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), energy dispersive X - ray spectroscopy (EDS), UV - Vis diffuse reflectance absorption spectra (UV - Vis DRS), photoluminescence (PL) spectra, transient photocurrent responses (TPC), and electrochemical impedance spectroscopy (EIS), and the possible reaction mechanism for the reduction of CO2 in the photocatalytic system was proposed.
A Z-scheme heterojunction photocatalyst Ag - Cu2 O/BiVO4 was successfully constructed with effective charge carrier separation/transfer by uniformly encapsulating Cu2O nanospheres and Ag nanoparticles on the surface of decahedral BiVO4 using a simple chemical reduction deposition strategy. The photo-reduction of carbon dioxide reaction result indicated that the as - prepared Ag - Cu2O/BiVO4 heterostructure exhibited excellent activity of photo-reduction CO2 with the CO yield of 5.37 μmol·g-1·h-1, about 35.8 times and 6.25 times of original BiVO4 and Cu2O, respectively. Ag-Cu2O/BiVO4 was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), energy dispersive X - ray spectroscopy (EDS), UV - Vis diffuse reflectance absorption spectra (UV - Vis DRS), photoluminescence (PL) spectra, transient photocurrent responses (TPC), and electrochemical impedance spectroscopy (EIS), and the possible reaction mechanism for the reduction of CO2 in the photocatalytic system was proposed.
2024, 40(5): 907-918
doi: 10.11862/CJIC.20230431
Abstract:
Based on the rigid benzene polycarboxylic acid H4BPTC (biphenyl-3, 3′, 5, 5′-tetracarboxylic acid), a 3D rigid zinc-based metal-organic framework with high-density free carboxyl oxygen modified pore walls, {[Zn2(BPTC) (H2O) (DMF)2]·DMF·H2O}n (SXNU-5-Zn), has been constructed. SXNU-5-Zn exhibited good acid-base stability within a pH range of 3-8 and excellent thermal stability. An electrochemical sensor, SXNU-5-Zn/GCE, based on a pure MOF material was constructed, which can detect paracetamol (AC) with high sensitivity and selectivity. The linear detection range spans from 0.02 to 765 μmol·L-1, with a limit of detection as low as 0.013 8 μmol·L-1 (S/N= 3). Furthermore, the prepared SXNU-5-Zn/GCE sensor has been successfully utilized to determine the AC content in compound acetaminophen tablets as an actual sample.
Based on the rigid benzene polycarboxylic acid H4BPTC (biphenyl-3, 3′, 5, 5′-tetracarboxylic acid), a 3D rigid zinc-based metal-organic framework with high-density free carboxyl oxygen modified pore walls, {[Zn2(BPTC) (H2O) (DMF)2]·DMF·H2O}n (SXNU-5-Zn), has been constructed. SXNU-5-Zn exhibited good acid-base stability within a pH range of 3-8 and excellent thermal stability. An electrochemical sensor, SXNU-5-Zn/GCE, based on a pure MOF material was constructed, which can detect paracetamol (AC) with high sensitivity and selectivity. The linear detection range spans from 0.02 to 765 μmol·L-1, with a limit of detection as low as 0.013 8 μmol·L-1 (S/N= 3). Furthermore, the prepared SXNU-5-Zn/GCE sensor has been successfully utilized to determine the AC content in compound acetaminophen tablets as an actual sample.
2024, 40(5): 919-929
doi: 10.11862/CJIC.20230421
Abstract:
To improve the catalytic activity of the photothermal CO2 hydrogenation In2O3 catalyst, a Mg(OH)2-In(OH)3 precursor was prepared by the homogeneous hydrothermal method, and a Mg-doped In2O3-x (Mg-In2O3-x) catalyst enriched with oxygen vacancies was obtained by the following high-temperature calcination and H2-reducing treatment. The catalyst was evaluated for its photothermal catalytic performance of CO2 hydrogenation in a photothermal fixed -bed reactor. The results demonstrated that Mg-In2O3-x achieved an impressive CO2 conversion rate of 31.20% with a CO production rate of 14.22 mmol·gcat-1·h-1 and selectivity of 100% in the light reaction at 300 ℃. The characterization results confirmed that the Mg doping into the In2O3 lattice promotes the formation of more surface oxygen vacancies, which dramatically increases the response efficiency to visible light and slows down the recombination of photogenerated electron-hole. This is the main reason for the enhancement of the photothermal catalytic performance.
To improve the catalytic activity of the photothermal CO2 hydrogenation In2O3 catalyst, a Mg(OH)2-In(OH)3 precursor was prepared by the homogeneous hydrothermal method, and a Mg-doped In2O3-x (Mg-In2O3-x) catalyst enriched with oxygen vacancies was obtained by the following high-temperature calcination and H2-reducing treatment. The catalyst was evaluated for its photothermal catalytic performance of CO2 hydrogenation in a photothermal fixed -bed reactor. The results demonstrated that Mg-In2O3-x achieved an impressive CO2 conversion rate of 31.20% with a CO production rate of 14.22 mmol·gcat-1·h-1 and selectivity of 100% in the light reaction at 300 ℃. The characterization results confirmed that the Mg doping into the In2O3 lattice promotes the formation of more surface oxygen vacancies, which dramatically increases the response efficiency to visible light and slows down the recombination of photogenerated electron-hole. This is the main reason for the enhancement of the photothermal catalytic performance.
2024, 40(5): 930-940
doi: 10.11862/CJIC.20230369
Abstract:
Using an interface engineering strategy, we successfully synthesized a core-shell nano-flower array of CuCo2O4/NiFe-layered bimetallic hydroxide (LDH) on nickel foam (NF) (CuCo2O4/NiFe-LDH@NF). The research indicates that electrons undergo transfer across the coupled interface of CuCo2O4 and NiFe-LDH, resulting in the enrichment of the CuCo2O4 core in electron density and thereby enhancing reaction kinetics. The amorphous NiFe-LDH shell not only provides additional channels for electron/material transport and increases active sites but also effectively shields the core CuCo2O4 from strong alkali corrosion during the oxygen evolution reaction (OER) in electrocatalysis. Therefore, when employed as an OER catalyst in a 1.0 mol·L-1 KOH solution, CuCo2O4/NiFe-LDH@NF required only a low overpotential of 191 mV to achieve a current density of 10 mA·cm-2 and a low Tafel slope of 31 mV·dec-1. Furthermore, CuCo2O4/NiFe-LDH@NF demonstrated stability in catalytic performance, crystal structure, morphological structure, and composition during prolonged operation.
Using an interface engineering strategy, we successfully synthesized a core-shell nano-flower array of CuCo2O4/NiFe-layered bimetallic hydroxide (LDH) on nickel foam (NF) (CuCo2O4/NiFe-LDH@NF). The research indicates that electrons undergo transfer across the coupled interface of CuCo2O4 and NiFe-LDH, resulting in the enrichment of the CuCo2O4 core in electron density and thereby enhancing reaction kinetics. The amorphous NiFe-LDH shell not only provides additional channels for electron/material transport and increases active sites but also effectively shields the core CuCo2O4 from strong alkali corrosion during the oxygen evolution reaction (OER) in electrocatalysis. Therefore, when employed as an OER catalyst in a 1.0 mol·L-1 KOH solution, CuCo2O4/NiFe-LDH@NF required only a low overpotential of 191 mV to achieve a current density of 10 mA·cm-2 and a low Tafel slope of 31 mV·dec-1. Furthermore, CuCo2O4/NiFe-LDH@NF demonstrated stability in catalytic performance, crystal structure, morphological structure, and composition during prolonged operation.
2024, 40(5): 941-952
doi: 10.11862/CJIC.20230398
Abstract:
TiO2-coated triangle Au with a core-shell structure (Au@TiO2) was synthesized using the sol-gel method. After hydrothermal crystallization, the particle size expanded to 300 nm with crystallization of the shell TiO2 into a mesoporous anatase phase, while the morphology of the triangle Au particle remained unchanged. The structure and properties of the samples were characterized using powder X-ray diffraction (PXRD), ζ potential, high-resolution transmission electron microscopy (HRTEM), thermogravimetric analysis (TGA), photoluminescence (PL) spectroscopy, photocurrent (i-t) measurements, and methylene blue (MB) photodegradation tests. The results revealed that the photocatalytic degradation rate of crystallized triangle Au@TiO2 was significantly higher than that of the amorphous material. Specifically, 1 mg·mL-1 Au@c-TiO2 achieved complete degradation of 60 mg·L-1 MB after one hour of visible light irradiation. An electron paramagnetic resonance (EPR) experiment was conducted, indicating that ·O2- and ·OH are the active species responsible for the degradation process. By combining experimental results with finite-difference time-domain (FDTD) analysis, we proposed a mechanism for the photodegradation process.
TiO2-coated triangle Au with a core-shell structure (Au@TiO2) was synthesized using the sol-gel method. After hydrothermal crystallization, the particle size expanded to 300 nm with crystallization of the shell TiO2 into a mesoporous anatase phase, while the morphology of the triangle Au particle remained unchanged. The structure and properties of the samples were characterized using powder X-ray diffraction (PXRD), ζ potential, high-resolution transmission electron microscopy (HRTEM), thermogravimetric analysis (TGA), photoluminescence (PL) spectroscopy, photocurrent (i-t) measurements, and methylene blue (MB) photodegradation tests. The results revealed that the photocatalytic degradation rate of crystallized triangle Au@TiO2 was significantly higher than that of the amorphous material. Specifically, 1 mg·mL-1 Au@c-TiO2 achieved complete degradation of 60 mg·L-1 MB after one hour of visible light irradiation. An electron paramagnetic resonance (EPR) experiment was conducted, indicating that ·O2- and ·OH are the active species responsible for the degradation process. By combining experimental results with finite-difference time-domain (FDTD) analysis, we proposed a mechanism for the photodegradation process.
2024, 40(5): 953-962
doi: 10.11862/CJIC.20230370
Abstract:
In an acidic environment, Fe3+ and Cu2+ reacted with KI solution to oxidize I- to I2, and I2 was used to etch Au nanorods (AuNRs) to produce a blue shift of the longitudinal surface plasmon resonance (LSPR) absorption peak of AuNRs to achieve the detection of Fe3+ and Cu2+. At a reaction temperature of 50 ℃, 0.8 mL HCl (0.1 mol· L-1), 2 mL KI (20 mmol· L-1), and 2 mL AuNRs solution were added in 2 mL 500 μmol·L-1 of Fe3+ or 30 μmol·L-1 of Cu2+ solution, and the Fe3+ or Cu2+ solution could etch AuNRs until the LSPR absorption peak of AuNRs disappeared after 25 or 90 min. The concentrations of Fe3+ and Cu2+ had a good linear relationship with the LSPR absorption peak shift of AuNRs, and the R2 was above 0.99. This method has excellent selectivity and accuracy for the detection of Fe3+ and Cu2+, with a maximum error of only 0.69% and 2.6%, respectively. For the detection of Fe3+ and Cu2+ coexistent system, the addition of an appropriate amount of F- in Fe3+ solution to form a complex [FeF6]3- can chemically mask Fe3+, which can eliminate the interference of Fe3+ in the coexistence system. The results showed that in a Cu2+ concentration range of 0-20 μmol·L-1, the LSPR absorption peaks of AuNRs before and after the addition of Fe3+-F- masking system were blue-shifted 217 and 210 nm, respectively. There was a good linear relationship between the Cu2+ concentration and the LSPR absorption peak shift of AuNRs, and the R2 was above 0.99. It can be concluded that the accurate detection of Cu2+ in the mixed system can be achieved by chemically masking the Fe3+ in the coexisting ions.
In an acidic environment, Fe3+ and Cu2+ reacted with KI solution to oxidize I- to I2, and I2 was used to etch Au nanorods (AuNRs) to produce a blue shift of the longitudinal surface plasmon resonance (LSPR) absorption peak of AuNRs to achieve the detection of Fe3+ and Cu2+. At a reaction temperature of 50 ℃, 0.8 mL HCl (0.1 mol· L-1), 2 mL KI (20 mmol· L-1), and 2 mL AuNRs solution were added in 2 mL 500 μmol·L-1 of Fe3+ or 30 μmol·L-1 of Cu2+ solution, and the Fe3+ or Cu2+ solution could etch AuNRs until the LSPR absorption peak of AuNRs disappeared after 25 or 90 min. The concentrations of Fe3+ and Cu2+ had a good linear relationship with the LSPR absorption peak shift of AuNRs, and the R2 was above 0.99. This method has excellent selectivity and accuracy for the detection of Fe3+ and Cu2+, with a maximum error of only 0.69% and 2.6%, respectively. For the detection of Fe3+ and Cu2+ coexistent system, the addition of an appropriate amount of F- in Fe3+ solution to form a complex [FeF6]3- can chemically mask Fe3+, which can eliminate the interference of Fe3+ in the coexistence system. The results showed that in a Cu2+ concentration range of 0-20 μmol·L-1, the LSPR absorption peaks of AuNRs before and after the addition of Fe3+-F- masking system were blue-shifted 217 and 210 nm, respectively. There was a good linear relationship between the Cu2+ concentration and the LSPR absorption peak shift of AuNRs, and the R2 was above 0.99. It can be concluded that the accurate detection of Cu2+ in the mixed system can be achieved by chemically masking the Fe3+ in the coexisting ions.
2024, 40(5): 963-971
doi: 10.11862/CJIC.20230293
Abstract:
The paper reports the synthesis of AgPd bimetallic hollow nanospheres at 70℃ by galvanic replacement reaction (GRR) coupled with a co-reduction method using Ag nanoparticles as sacrificial templates, H2PdCl4 as precursor, ascorbic acid as reductant, and polyvinyl pyrrolidone as capping agent. To characterize the structures, compositions, and morphologies of the products prepared with different H2PdCl4 solution volumes, UV-Vis spectra, powder X-ray diffraction, and transmission electron microscope coupled with an energy dispersive spectrometer were used. The results indicate the interior caves of nanospheres gradually become big and densities decrease with the increase of volume of the H2PdCl4 solution. Simultaneously, the sizes of nanoparticles increase. When the volume of the H2PdCl4 solution was increased to 120 μL, we synthesized the uniform hollow AgPd bimetallic nanospheres with outer sizes of about 25 nm and wall thicknesses of 2-3 nm. The catalytic activities of Ag, Pd, and AgPd bimetals were evaluated using the catalytic hydrogenation of 4-nitrophenol by an excess of NaBH4 at room temperature. The AgPd bimetals showed superior catalytic activities than pure Ag and Pd due to electron transfer from Ag to Pd. The reaction rate constant of AgPd-120 nano hollow sphere (120 μL of H2PdCl4 solution) as a catalyst was the highest, which was 24.0 times that of pure Ag nanospheres of the same size and 14.7 times that of pure Pd nanocubes
The paper reports the synthesis of AgPd bimetallic hollow nanospheres at 70℃ by galvanic replacement reaction (GRR) coupled with a co-reduction method using Ag nanoparticles as sacrificial templates, H2PdCl4 as precursor, ascorbic acid as reductant, and polyvinyl pyrrolidone as capping agent. To characterize the structures, compositions, and morphologies of the products prepared with different H2PdCl4 solution volumes, UV-Vis spectra, powder X-ray diffraction, and transmission electron microscope coupled with an energy dispersive spectrometer were used. The results indicate the interior caves of nanospheres gradually become big and densities decrease with the increase of volume of the H2PdCl4 solution. Simultaneously, the sizes of nanoparticles increase. When the volume of the H2PdCl4 solution was increased to 120 μL, we synthesized the uniform hollow AgPd bimetallic nanospheres with outer sizes of about 25 nm and wall thicknesses of 2-3 nm. The catalytic activities of Ag, Pd, and AgPd bimetals were evaluated using the catalytic hydrogenation of 4-nitrophenol by an excess of NaBH4 at room temperature. The AgPd bimetals showed superior catalytic activities than pure Ag and Pd due to electron transfer from Ag to Pd. The reaction rate constant of AgPd-120 nano hollow sphere (120 μL of H2PdCl4 solution) as a catalyst was the highest, which was 24.0 times that of pure Ag nanospheres of the same size and 14.7 times that of pure Pd nanocubes
