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2024 Volume 40 Issue 6
2024, 40(6): 1033-1064
doi: 10.11862/CJIC.20230371
Abstract:
Interfacial solar evaporation devices for desalination have attracted significant attention due to their ecofriendliness, simplicity, high efficiency, and versatility. In contrast to traditional volumetric evaporation devices, interfacial solar evaporation devices confine the collection of sunlight and steam generation to the air-water interface, avoiding the need to heat the entire water volume from the bottom to generate vapor, thus greatly improving energy utilization efficiency. This paper details the photothermal conversion mechanisms, types, and performance of the photothermal materials, which are one of the important components of interfacial solar vapor generators. Then, the device design strategies for efficient seawater purification are thoroughly discussed, including the enhancement of light absorption, the supply of sufficient water, and the resistance and elimination of salt. Based on these discussions, the research progress of interfacial solar evaporation devices is summarized, and the development prospects of novel solar evaporation devices for desalination are anticipated.
Interfacial solar evaporation devices for desalination have attracted significant attention due to their ecofriendliness, simplicity, high efficiency, and versatility. In contrast to traditional volumetric evaporation devices, interfacial solar evaporation devices confine the collection of sunlight and steam generation to the air-water interface, avoiding the need to heat the entire water volume from the bottom to generate vapor, thus greatly improving energy utilization efficiency. This paper details the photothermal conversion mechanisms, types, and performance of the photothermal materials, which are one of the important components of interfacial solar vapor generators. Then, the device design strategies for efficient seawater purification are thoroughly discussed, including the enhancement of light absorption, the supply of sufficient water, and the resistance and elimination of salt. Based on these discussions, the research progress of interfacial solar evaporation devices is summarized, and the development prospects of novel solar evaporation devices for desalination are anticipated.
2024, 40(6): 1065-1078
doi: 10.11862/CJIC.20240099
Abstract:
The improved Hummers method was used to obtain GOQDs from flake graphite, which contained rich hydroxyl and carboxyl groups. With the as-fabricated GOQDs in hand, we constructed a GOQDs/OVA nano-vaccine using chicken ovalbumin (OVA) as a model antigen to evaluate the immune efficacy and safety. Results showed that GOQDs/OVA nano-vaccine had high water dispersibility and stability with a diameter of around 5 nm for 30 d. The maximum loading capacity of GOQDs for OVA was about 500 mg·g-1, and release rates of OVA were 74.65% and 56.93% in pH 5.5 and 7.4 after 24 h, respectively, displaying pH stimulus responsive release merits. With the concentration of GOQDs below 500 μg·mL-1, the biosecurity of GOQDs indicated that they were not causing hemolysis, cell damage, and pathological changes in important tissues. After immunization, GOQDs/OVA nano-vaccines could excite the high levels of immunoglobulin G (IgG), immunoglobulin G1 (IgG1), and immunoglobulin G2a (IgG2a) antibodies and improve secretions of interleukin-1β (IL-1β), interleukin-4 (IL-2), interleukin-4 (IL-4), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ), compared with the group of OVA alone. Meanwhile, GOQDs promoted an increase in the percentage of CD4+ and CD8+ T lymphocytes in the spleen.
The improved Hummers method was used to obtain GOQDs from flake graphite, which contained rich hydroxyl and carboxyl groups. With the as-fabricated GOQDs in hand, we constructed a GOQDs/OVA nano-vaccine using chicken ovalbumin (OVA) as a model antigen to evaluate the immune efficacy and safety. Results showed that GOQDs/OVA nano-vaccine had high water dispersibility and stability with a diameter of around 5 nm for 30 d. The maximum loading capacity of GOQDs for OVA was about 500 mg·g-1, and release rates of OVA were 74.65% and 56.93% in pH 5.5 and 7.4 after 24 h, respectively, displaying pH stimulus responsive release merits. With the concentration of GOQDs below 500 μg·mL-1, the biosecurity of GOQDs indicated that they were not causing hemolysis, cell damage, and pathological changes in important tissues. After immunization, GOQDs/OVA nano-vaccines could excite the high levels of immunoglobulin G (IgG), immunoglobulin G1 (IgG1), and immunoglobulin G2a (IgG2a) antibodies and improve secretions of interleukin-1β (IL-1β), interleukin-4 (IL-2), interleukin-4 (IL-4), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ), compared with the group of OVA alone. Meanwhile, GOQDs promoted an increase in the percentage of CD4+ and CD8+ T lymphocytes in the spleen.
2024, 40(6): 1079-1087
doi: 10.11862/CJIC.20240036
Abstract:
A nano-thin layer MWW-type zeolite, derived from fumed silica, was dynamically in-situ synthesized at 150 ℃ using a dual-template system of cetyltrimethylammonium bromide (CTAB) and hexamethylene imine(HMI). The effect of CTAB amount on the zeolite was also investigated. The nano-thin layer samples were characterized using powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), N2 adsorption-desorption, ammonia temperature programmed desorption (NH3-TPD), high-resolution transmission electron microscopy (HRTEM), pyridine infrared spectroscopy (Py-IR), and 2, 6-di-tert-butylpyridine infrared spectroscopy (DTBPy-IR). The results indicated that MWW nanosheets with a thickness of 5-10 nm can be prepared using the double template system. Furthermore, the catalytic performance of the samples was evaluated through the isomerization of the trimethylbenzenes reaction. The catalytic results show that the sample d-MWW-4%CTAB exhibits good catalytic performance, with the conversion of 1, 2, 4-trimethylbenzene, the yield of 1, 3, 5-trimethylbenzene, and the selectivity of 1, 3, 5-trimethylbenzene being 34.97%, 22.42%, and 64.09%, respectively. This is primarily attributed to the external surface area and interlayer mesoporous structure formed in the nano-thin layer MCM-22.
A nano-thin layer MWW-type zeolite, derived from fumed silica, was dynamically in-situ synthesized at 150 ℃ using a dual-template system of cetyltrimethylammonium bromide (CTAB) and hexamethylene imine(HMI). The effect of CTAB amount on the zeolite was also investigated. The nano-thin layer samples were characterized using powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), N2 adsorption-desorption, ammonia temperature programmed desorption (NH3-TPD), high-resolution transmission electron microscopy (HRTEM), pyridine infrared spectroscopy (Py-IR), and 2, 6-di-tert-butylpyridine infrared spectroscopy (DTBPy-IR). The results indicated that MWW nanosheets with a thickness of 5-10 nm can be prepared using the double template system. Furthermore, the catalytic performance of the samples was evaluated through the isomerization of the trimethylbenzenes reaction. The catalytic results show that the sample d-MWW-4%CTAB exhibits good catalytic performance, with the conversion of 1, 2, 4-trimethylbenzene, the yield of 1, 3, 5-trimethylbenzene, and the selectivity of 1, 3, 5-trimethylbenzene being 34.97%, 22.42%, and 64.09%, respectively. This is primarily attributed to the external surface area and interlayer mesoporous structure formed in the nano-thin layer MCM-22.
2024, 40(6): 1088-1094
doi: 10.11862/CJIC.20240006
Abstract:
Reaction of [OsGe(ArTrip)(PPh3)(H)Cl2] (1), where ArTrip=C6H3-2-(η6-Trip)-6-Trip and Trip=2, 4, 6-iPr3-C6H3, with Grignard reagent EtMgBr afforded [OsGe(ArTrip)(PPh3)(H)Br2] (2) and [OsGe(ArTrip)(PPh3)(H)Et2] (3), respectively, depending on the temperature and reaction molar ratio. Unexpected formation of 2 and 3 underwent replacement of Cl atom on Ge center with Br instead of Et group. In addition, the treatment of 1 with LiHBEt3 also led to the formation of 3 without hydrogenation. Moreover, complex 1 reacted with HBF4 to yield additional product [OsGe(ArTrip)(PPh3)(H)2Cl2]BF4 (4), which converted back to 1 in the presence of H2O (nH2O/n4=1).
Reaction of [OsGe(ArTrip)(PPh3)(H)Cl2] (1), where ArTrip=C6H3-2-(η6-Trip)-6-Trip and Trip=2, 4, 6-iPr3-C6H3, with Grignard reagent EtMgBr afforded [OsGe(ArTrip)(PPh3)(H)Br2] (2) and [OsGe(ArTrip)(PPh3)(H)Et2] (3), respectively, depending on the temperature and reaction molar ratio. Unexpected formation of 2 and 3 underwent replacement of Cl atom on Ge center with Br instead of Et group. In addition, the treatment of 1 with LiHBEt3 also led to the formation of 3 without hydrogenation. Moreover, complex 1 reacted with HBF4 to yield additional product [OsGe(ArTrip)(PPh3)(H)2Cl2]BF4 (4), which converted back to 1 in the presence of H2O (nH2O/n4=1).
2024, 40(6): 1095-1104
doi: 10.11862/CJIC.20240002
Abstract:
An optical probe (3) with a donor-π-acceptor (D-π-A) structure for the detection of hypochlorous acid (HClO) was synthesized by a one-step reaction. It employed a barbituric acid derivative as the electron acceptor and 4-(dimethylamino)cinnamaldehyde as the electron donor. The probe exhibited high sensitivity and selectivity for the detection of HClO, rapidly responding with distinct colorimetric and fluorescent "on-off" signals (about 15 s). The probe displayed a linear relationship between fluorescence intensity and HClO concentration, with a low detection limit (LOD) of 14 nmol·L-1, which made it suitable for quantitative HClO detection. Moreover, the probe exhibited red light emission (628 nm) with a significant Stokes shift (158 nm) and good photostability, which provided advantages for its application in cell imaging. The proposed reaction mechanism, which was deduced from high-resolution mass spectrometry data, involved electrophilic addition and oxidative cleavage of the C=C bond by ClO-, which led to the disruption of the probe′s D-π-A structure. Consequently, this effectively halted the intramolecular charge transfer (ICT) process of the probe. MTT cytotoxicity assays demonstrated minimal toxicity of the probe following 12, 24, and 48 h of incubation with HepG2 cells. The probe was successfully applied to living cell imaging and enabled the detection of HClO via fluorescence quenching within the living cellular milieu.
An optical probe (3) with a donor-π-acceptor (D-π-A) structure for the detection of hypochlorous acid (HClO) was synthesized by a one-step reaction. It employed a barbituric acid derivative as the electron acceptor and 4-(dimethylamino)cinnamaldehyde as the electron donor. The probe exhibited high sensitivity and selectivity for the detection of HClO, rapidly responding with distinct colorimetric and fluorescent "on-off" signals (about 15 s). The probe displayed a linear relationship between fluorescence intensity and HClO concentration, with a low detection limit (LOD) of 14 nmol·L-1, which made it suitable for quantitative HClO detection. Moreover, the probe exhibited red light emission (628 nm) with a significant Stokes shift (158 nm) and good photostability, which provided advantages for its application in cell imaging. The proposed reaction mechanism, which was deduced from high-resolution mass spectrometry data, involved electrophilic addition and oxidative cleavage of the C=C bond by ClO-, which led to the disruption of the probe′s D-π-A structure. Consequently, this effectively halted the intramolecular charge transfer (ICT) process of the probe. MTT cytotoxicity assays demonstrated minimal toxicity of the probe following 12, 24, and 48 h of incubation with HepG2 cells. The probe was successfully applied to living cell imaging and enabled the detection of HClO via fluorescence quenching within the living cellular milieu.
2024, 40(6): 1105-1113
doi: 10.11862/CJIC.20230488
Abstract:
To solve the bottleneck problem of lattice oxygen precipitation during the cycling process of lithium-rich manganese-based anode materials and the poor cycling performance due to the lithium-rich phase of the poor conductor of electrons, the ultra-wideband semiconductor material Ga2O3 for its in-situ coating modification was adopted. The purpose of the surface modification is to improve its electronic conductivity to increase the multiplicity of performance, and at the same time, the C2/m space group of the Ga2O3 coating layer can both improve the Li+ migration rate and inhibit the Li+ migration rate. It can also inhibit the lattice oxygen precipitation of Li-rich manganese-based materials. A pristine sample of Li-rich manganese-based cathode materials Li1.2Mn0.54Ni0.13Co0.13O2 (P-LRMO) was prepared by co-precipitation method, and in-situ coated with different contents of Ga2O3 by simple wet-chemical method as well as low-temperature calcination method. The results of transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) showed that the Ga2O3 coating layer was successfully synthesized on the surface of the pristine sample. The results of electrochemical tests showed that the modified material G3-LRMO with mass fraction of 3% Ga2O3 had the best electrochemical performance, which could reach 270.1 mAh·g-1 in the first cycle of the charge-discharge at 0.1C (25 mA·g-1), and still maintained 127.4 mAh·g-1 at 5C, which was better than 90.7 mAh·g-1 of the unmodified material. G3-LRMO still had a capacity of 190.7 mAh·g-1 after 200 cycles at 1C, and the capacity retention rate increased from 72.9% to 85.6%, which proves that the modification of Ga2O3 coating can improve the cycling stability of lithium-rich manganese-based materials. Moreover, the charge transfer impedance (Rct) of the G3-LRMO material was 107.7 Ω after 100 cycles at 1C, which is much lower than that of the unmodified material (251.5 Ω), indicating that the Ga2O3 coating layer can improve the electron transfer rate of the material.
To solve the bottleneck problem of lattice oxygen precipitation during the cycling process of lithium-rich manganese-based anode materials and the poor cycling performance due to the lithium-rich phase of the poor conductor of electrons, the ultra-wideband semiconductor material Ga2O3 for its in-situ coating modification was adopted. The purpose of the surface modification is to improve its electronic conductivity to increase the multiplicity of performance, and at the same time, the C2/m space group of the Ga2O3 coating layer can both improve the Li+ migration rate and inhibit the Li+ migration rate. It can also inhibit the lattice oxygen precipitation of Li-rich manganese-based materials. A pristine sample of Li-rich manganese-based cathode materials Li1.2Mn0.54Ni0.13Co0.13O2 (P-LRMO) was prepared by co-precipitation method, and in-situ coated with different contents of Ga2O3 by simple wet-chemical method as well as low-temperature calcination method. The results of transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) showed that the Ga2O3 coating layer was successfully synthesized on the surface of the pristine sample. The results of electrochemical tests showed that the modified material G3-LRMO with mass fraction of 3% Ga2O3 had the best electrochemical performance, which could reach 270.1 mAh·g-1 in the first cycle of the charge-discharge at 0.1C (25 mA·g-1), and still maintained 127.4 mAh·g-1 at 5C, which was better than 90.7 mAh·g-1 of the unmodified material. G3-LRMO still had a capacity of 190.7 mAh·g-1 after 200 cycles at 1C, and the capacity retention rate increased from 72.9% to 85.6%, which proves that the modification of Ga2O3 coating can improve the cycling stability of lithium-rich manganese-based materials. Moreover, the charge transfer impedance (Rct) of the G3-LRMO material was 107.7 Ω after 100 cycles at 1C, which is much lower than that of the unmodified material (251.5 Ω), indicating that the Ga2O3 coating layer can improve the electron transfer rate of the material.
2024, 40(6): 1114-1122
doi: 10.11862/CJIC.20230473
Abstract:
Mn2+-doped quasi-two-dimensional perovskite (PEA)2PbyMn1-yBr4 (PEA is phenylethylamine, y is the fraction of Pb2+ in the total content of Mn2+ and Pb2+) thin films were prepared successfully with high photoluminescence quantum yield (PLQY). It constructed a dual-emissive excited state transfer system, while (PEA)2PbBr4 and impurity Mn2+ respectively act as the donor and acceptor. Mn2+ incorporation improved the luminescence properties and film morphologies. Using the femtosecond transient absorption (TA) measurement, we demonstrated the charge transfer processes between the host and the guest. To study the electroluminescence properties, (PEA)2PbyMn1-yBr4 film was employed as the active layer to fabricate LED (light emitting diodes, LEDs) devices. The (PEA)2PbyMn1-yBr4 LED device emitted a bright orange color, which demonstrated a maximum luminous intensity of 0.21 cd·m-2 with an external quantum efficiency (EQE) of 0.002 5%.
Mn2+-doped quasi-two-dimensional perovskite (PEA)2PbyMn1-yBr4 (PEA is phenylethylamine, y is the fraction of Pb2+ in the total content of Mn2+ and Pb2+) thin films were prepared successfully with high photoluminescence quantum yield (PLQY). It constructed a dual-emissive excited state transfer system, while (PEA)2PbBr4 and impurity Mn2+ respectively act as the donor and acceptor. Mn2+ incorporation improved the luminescence properties and film morphologies. Using the femtosecond transient absorption (TA) measurement, we demonstrated the charge transfer processes between the host and the guest. To study the electroluminescence properties, (PEA)2PbyMn1-yBr4 film was employed as the active layer to fabricate LED (light emitting diodes, LEDs) devices. The (PEA)2PbyMn1-yBr4 LED device emitted a bright orange color, which demonstrated a maximum luminous intensity of 0.21 cd·m-2 with an external quantum efficiency (EQE) of 0.002 5%.
2024, 40(6): 1123-1134
doi: 10.11862/CJIC.20230477
Abstract:
The multilevel Ag/Bi/Nv-g-C3N4/Ti3C2Tx (Nv-g-C3N4: nitrogen vacancy-g-C3N4) Schottky junction was prepared via an in-situ solvothermal reaction. The phase composition and crystal structure, micromorphology and pore structure, surface elemental composition and chemical state, and optical and photoelectrochemical properties were characterized. The prepared Ag/Bi/Nv-g-C3N4/Ti3C2Tx exhibited full-spectrum absorption characteristics owing to the synergistic surface plasmon resonance effect between Ag, Bi, and Ti3C2Tx. Moreover, the Schottky junction was formed through the interface polarization charge transfer driven by carrier concentration difference, resulting in the markedly improved separation efficiency and utilization of photogenerated carriers (including hot electrons and hot holes). Consequently, in comparison to Nv-g-C3N4, Ti3C2Tx, Ag/Nv-g-C3N4, Bi/Nv-g-C3N4, and Ag/Bi/Nv-g-C3N4, Ag/Bi/Nv-g-C3N4/Ti3C2Tx showed significantly enhanced full-spectrum-driven photocatalytic activity, and the reaction rate constants for photocatalytic degradation of tetracycline under visible light and near-infrared light irradiation could reach 0.033 and 0.008 6 min-1, respectively, which were approximately 10-2.1 times and 8.6-1.8 times higher than those of contract samples.
The multilevel Ag/Bi/Nv-g-C3N4/Ti3C2Tx (Nv-g-C3N4: nitrogen vacancy-g-C3N4) Schottky junction was prepared via an in-situ solvothermal reaction. The phase composition and crystal structure, micromorphology and pore structure, surface elemental composition and chemical state, and optical and photoelectrochemical properties were characterized. The prepared Ag/Bi/Nv-g-C3N4/Ti3C2Tx exhibited full-spectrum absorption characteristics owing to the synergistic surface plasmon resonance effect between Ag, Bi, and Ti3C2Tx. Moreover, the Schottky junction was formed through the interface polarization charge transfer driven by carrier concentration difference, resulting in the markedly improved separation efficiency and utilization of photogenerated carriers (including hot electrons and hot holes). Consequently, in comparison to Nv-g-C3N4, Ti3C2Tx, Ag/Nv-g-C3N4, Bi/Nv-g-C3N4, and Ag/Bi/Nv-g-C3N4, Ag/Bi/Nv-g-C3N4/Ti3C2Tx showed significantly enhanced full-spectrum-driven photocatalytic activity, and the reaction rate constants for photocatalytic degradation of tetracycline under visible light and near-infrared light irradiation could reach 0.033 and 0.008 6 min-1, respectively, which were approximately 10-2.1 times and 8.6-1.8 times higher than those of contract samples.
2024, 40(6): 1135-1142
doi: 10.11862/CJIC.20230459
Abstract:
MnO2-0.39IrOx (0.39 was the atomic ratio of Ir/Mn) catalysts were successfully prepared by the Adams method and applied for efficient oxygen precipitation reaction (OER) in an acidic medium. During the electrochemical measurement, MnO2-0.39IrOx enabled the water oxidation process to reach a current density of 10 mA·cm-2 with an overpotential of only 253 mV and maintained a stable test for more than 200 h. In addition, the noble metal Ir mass activity of MnO2-0.39IrOx was 61.3 mA·mg-1 at a potential of 1.50 V (vs RHE), which was 35.8 times higher than that of IrO2, increasing the precious metal utilization. Structural analysis revealed that the unique lamellar structure of MnO2-0.39IrOx substantially improves the electrochemically active surface of the catalysts and that there are certain electronic interactions between the Ir sites and the Mn sites. The analysis of the catalytic process showed that the MnO2-0.39IrOx surface showed some reconfiguration phenomenon and the Mn components achieved a continuous optimization of the chemical environment of the Ir sites, which led to the efficient acidic OER performance of the catalyst.
MnO2-0.39IrOx (0.39 was the atomic ratio of Ir/Mn) catalysts were successfully prepared by the Adams method and applied for efficient oxygen precipitation reaction (OER) in an acidic medium. During the electrochemical measurement, MnO2-0.39IrOx enabled the water oxidation process to reach a current density of 10 mA·cm-2 with an overpotential of only 253 mV and maintained a stable test for more than 200 h. In addition, the noble metal Ir mass activity of MnO2-0.39IrOx was 61.3 mA·mg-1 at a potential of 1.50 V (vs RHE), which was 35.8 times higher than that of IrO2, increasing the precious metal utilization. Structural analysis revealed that the unique lamellar structure of MnO2-0.39IrOx substantially improves the electrochemically active surface of the catalysts and that there are certain electronic interactions between the Ir sites and the Mn sites. The analysis of the catalytic process showed that the MnO2-0.39IrOx surface showed some reconfiguration phenomenon and the Mn components achieved a continuous optimization of the chemical environment of the Ir sites, which led to the efficient acidic OER performance of the catalyst.
2024, 40(6): 1143-1150
doi: 10.11862/CJIC.20230271
Abstract:
The present report deals with the synthesis of the two MOFs of respective formula {[Nd2(L)3(DMF)2(H2O)2]·2DMF}n (1) and {[Gd2(L)3(DMF)2(H2O)2]·2DMF}n (2) were synthesized by solvothermal method using 2, 5-dibromo-terephthalic acid (H2L) as a ligand and reacting with neodymium nitrate hexahydrate and gadolinium nitrate hexahydrate, respectively. The structures of both of them were elucidated by single-crystal X-ray diffraction and powder X-ray diffraction to demonstrate that complexes 1 and 2 crystallize in a similar space group P1 as a triclinic system with high crystal purity. Meanwhile, the complexes were characterized by elemental analysis, IR spectroscopy, UV-Vis absorption spectroscopy, fluorescence, and thermal analysis. Single-crystal X-ray diffraction analysis demonstrates the complexes are connected to the ligand with rare earth ions as metal nodes, forming an infinitely extended 3D network structure.
The present report deals with the synthesis of the two MOFs of respective formula {[Nd2(L)3(DMF)2(H2O)2]·2DMF}n (1) and {[Gd2(L)3(DMF)2(H2O)2]·2DMF}n (2) were synthesized by solvothermal method using 2, 5-dibromo-terephthalic acid (H2L) as a ligand and reacting with neodymium nitrate hexahydrate and gadolinium nitrate hexahydrate, respectively. The structures of both of them were elucidated by single-crystal X-ray diffraction and powder X-ray diffraction to demonstrate that complexes 1 and 2 crystallize in a similar space group P1 as a triclinic system with high crystal purity. Meanwhile, the complexes were characterized by elemental analysis, IR spectroscopy, UV-Vis absorption spectroscopy, fluorescence, and thermal analysis. Single-crystal X-ray diffraction analysis demonstrates the complexes are connected to the ligand with rare earth ions as metal nodes, forming an infinitely extended 3D network structure.
2024, 40(6): 1151-1161
doi: 10.11862/CJIC.20230454
Abstract:
The multistage microporous electrocatalysts to assist the energy-efficient hydrogen generation from water electrolysis were fabricated on the surface of three-dimensional porous foam (NF) by a one-step hydrothermal synthesis strategy. When the molar ratio of sulfur to phosphorus in the initial mixed solution was 1∶1, an amorphous P-doped nickel-based sulfide (NiSP/NF) electrocatalyst, with Ni3S2 and NiPS3 as the main and secondary crystalline phase, respectively, was obtained by hydrothermal treatment at 120 ℃ for 24 h. Thanks to its unique bi-hierarchy microporous structure composed of interwoven interconnected ultra-thin nanosheets, yielding the nearly 14-fold increased electrochemical active surface area (ECSA), sufficient active sites and interface channels are provided for hydrogen evolution reaction (HER) during water splitting. Meanwhile, benefiting from the lattice defects created by crystalline Ni3S2 and the strong electronic interactions with crystalline P doping phases, respectively, the intrinsically catalytic activity of nickel-based electrocatalyst was significantly enhanced. The synergistic effects enable NiSP/NF to exhibit remarkable performances during the whole water splitting, achieving a current density of 10 mA·cm-2 in 1 mol·L-1 KOH solution with overpotentials for HER and OER as low as 67 and 212 mV, respectively. Assembled as an electrolyzer for overall water splitting (OWS), a current density of 100 mA·cm-2 can be achieved only needing a cell voltage of 1.878 V, even at 500 mA·cm-2 the needed cell voltage was only 2.558 V for NiSP/NF, which is dramatically superior to noble metal catalysts and helpful to improve hydrogen production efficiency for water electrolysis. Particularly, as a bifunctional electrocatalyst, NiSP/NF also exhibited excellent long-term stability and durability, because of less than a 0.03 V cell voltage increase after running a 120-hour chronopotentiometric test at 500 mA·cm-2.
The multistage microporous electrocatalysts to assist the energy-efficient hydrogen generation from water electrolysis were fabricated on the surface of three-dimensional porous foam (NF) by a one-step hydrothermal synthesis strategy. When the molar ratio of sulfur to phosphorus in the initial mixed solution was 1∶1, an amorphous P-doped nickel-based sulfide (NiSP/NF) electrocatalyst, with Ni3S2 and NiPS3 as the main and secondary crystalline phase, respectively, was obtained by hydrothermal treatment at 120 ℃ for 24 h. Thanks to its unique bi-hierarchy microporous structure composed of interwoven interconnected ultra-thin nanosheets, yielding the nearly 14-fold increased electrochemical active surface area (ECSA), sufficient active sites and interface channels are provided for hydrogen evolution reaction (HER) during water splitting. Meanwhile, benefiting from the lattice defects created by crystalline Ni3S2 and the strong electronic interactions with crystalline P doping phases, respectively, the intrinsically catalytic activity of nickel-based electrocatalyst was significantly enhanced. The synergistic effects enable NiSP/NF to exhibit remarkable performances during the whole water splitting, achieving a current density of 10 mA·cm-2 in 1 mol·L-1 KOH solution with overpotentials for HER and OER as low as 67 and 212 mV, respectively. Assembled as an electrolyzer for overall water splitting (OWS), a current density of 100 mA·cm-2 can be achieved only needing a cell voltage of 1.878 V, even at 500 mA·cm-2 the needed cell voltage was only 2.558 V for NiSP/NF, which is dramatically superior to noble metal catalysts and helpful to improve hydrogen production efficiency for water electrolysis. Particularly, as a bifunctional electrocatalyst, NiSP/NF also exhibited excellent long-term stability and durability, because of less than a 0.03 V cell voltage increase after running a 120-hour chronopotentiometric test at 500 mA·cm-2.
2024, 40(6): 1162-1172
doi: 10.11862/CJIC.20240087
Abstract:
Two mononuclear cobalt(Ⅱ) complexes, [Co(pytpy)2](2-NH2-1-NS)2·MeOH·H2O (1) and [Co(pytpy)2](4-NH2-1-NS)2·H2O (2), where pytpy=4'-(4-pyridyl)-2, 2'∶6', 2″-terpyridine, 2-NH2-1-NS-=2-amino-1-naphthalenesulfonate, and 4-NH2-1-NS-=4-amino-1-naphthalenesulfonate, were synthesized and characterized structurally and magnetically. Single-crystal X-ray analysis reveals that both complexes consist of the [Co(pytpy)2]2+ cations, organosulfonate anions, and crystallized solvent molecules. The difference between the two anions is the relative position of the sulfonate and amino groups. Interestingly, the 2-NH2-1-NS- anion with the sulfonate and amino group in adjacent positions, forms hydrogen bonds with the [Co(pytpy)2]2+ cation and solvent molecules, while the 4-NH2-1-NS- anion, with the sulfonate and amino groups in para positions, forms a 2D layer structure through hydrogen bonding. Magnetic measurements revealed significant differences in their magnetic properties: while complex 1 exhibits a reversible and gradual spin crossover behavior, complex 2 remains in the high-spin state.
Two mononuclear cobalt(Ⅱ) complexes, [Co(pytpy)2](2-NH2-1-NS)2·MeOH·H2O (1) and [Co(pytpy)2](4-NH2-1-NS)2·H2O (2), where pytpy=4'-(4-pyridyl)-2, 2'∶6', 2″-terpyridine, 2-NH2-1-NS-=2-amino-1-naphthalenesulfonate, and 4-NH2-1-NS-=4-amino-1-naphthalenesulfonate, were synthesized and characterized structurally and magnetically. Single-crystal X-ray analysis reveals that both complexes consist of the [Co(pytpy)2]2+ cations, organosulfonate anions, and crystallized solvent molecules. The difference between the two anions is the relative position of the sulfonate and amino groups. Interestingly, the 2-NH2-1-NS- anion with the sulfonate and amino group in adjacent positions, forms hydrogen bonds with the [Co(pytpy)2]2+ cation and solvent molecules, while the 4-NH2-1-NS- anion, with the sulfonate and amino groups in para positions, forms a 2D layer structure through hydrogen bonding. Magnetic measurements revealed significant differences in their magnetic properties: while complex 1 exhibits a reversible and gradual spin crossover behavior, complex 2 remains in the high-spin state.
2024, 40(6): 1173-1179
doi: 10.11862/CJIC.20240039
Abstract:
A new sandwich-type {Co6}-added polyoxotungstate, [Co(dien)2]{[Co(dien)(H2O)]2[Co(dien)]2[Co6(en)2(μ3-OH)2(H2O)6(GeW8O31)2]}·5.5H2O (1), where dien=diethylenetriamine and en=ethylenediamine, was synthesized via hydrothermal reaction. The polyoxoanion of compound 1 was constructed by a belt-like {Co6} cluster core sandwiched by two {GeW8} units. 1 was characterized by single crystal X-ray diffraction, element analysis, IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA) experiments, respectively. The electrochemical properties of 1 were explored by the cyclic voltammetry (CV) technique, and 1 exhibited excellent electrocatalytic activity in nitrite reduction.
A new sandwich-type {Co6}-added polyoxotungstate, [Co(dien)2]{[Co(dien)(H2O)]2[Co(dien)]2[Co6(en)2(μ3-OH)2(H2O)6(GeW8O31)2]}·5.5H2O (1), where dien=diethylenetriamine and en=ethylenediamine, was synthesized via hydrothermal reaction. The polyoxoanion of compound 1 was constructed by a belt-like {Co6} cluster core sandwiched by two {GeW8} units. 1 was characterized by single crystal X-ray diffraction, element analysis, IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA) experiments, respectively. The electrochemical properties of 1 were explored by the cyclic voltammetry (CV) technique, and 1 exhibited excellent electrocatalytic activity in nitrite reduction.
2024, 40(6): 1180-1188
doi: 10.11862/CJIC.20230489
Abstract:
A Cd(Ⅱ) complex, formulated as {(H2dbim)0.5[Cd(Hbptc)]·H2O}n (1), where dbim=1-(4-((2, 6-dimethyl-2H-benzo[d]imidazol-3(3H)-yl)methyl)benzyl)-2, 7-dihydro-2, 5-dimethyl-1H-benzo[d]imidazole, H4bptc=3, 3', 4, 4'-benzophenone tetracarboxylic acid, has been obtained by hydrothermal reactions and structurally characterized. Complex 1 exhibits a 2D layer with a point symbol of {44·66}. Complex 1 was used for fluorescence identification of some common environmental pollutants. The result of the research shows that complex 1 can effectively detect p-nitrophenol, tetracycline, and 2, 6-dichloro-4-nitroaniline. The calculated quenching constants for p-nitrophenol, tetracycline, and 2, 6-dichloro-4-nitroaniline were 2×102, 5.4×104, and 2×104 L·mol-1, respectively.
A Cd(Ⅱ) complex, formulated as {(H2dbim)0.5[Cd(Hbptc)]·H2O}n (1), where dbim=1-(4-((2, 6-dimethyl-2H-benzo[d]imidazol-3(3H)-yl)methyl)benzyl)-2, 7-dihydro-2, 5-dimethyl-1H-benzo[d]imidazole, H4bptc=3, 3', 4, 4'-benzophenone tetracarboxylic acid, has been obtained by hydrothermal reactions and structurally characterized. Complex 1 exhibits a 2D layer with a point symbol of {44·66}. Complex 1 was used for fluorescence identification of some common environmental pollutants. The result of the research shows that complex 1 can effectively detect p-nitrophenol, tetracycline, and 2, 6-dichloro-4-nitroaniline. The calculated quenching constants for p-nitrophenol, tetracycline, and 2, 6-dichloro-4-nitroaniline were 2×102, 5.4×104, and 2×104 L·mol-1, respectively.
2024, 40(6): 1189-1200
doi: 10.11862/CJIC.20230482
Abstract:
The adsorption behaviors of intrinsic graphene-like GaN (g-GaN) and transition metal (TM) atom-doped g-GaN on Cl2 and CO gas molecules were systematically investigated using first-principles calculations based on density functional theory. The results show that the adsorption of both Cl2 and CO on the intrinsic g-GaN was physisorbed, and since the adsorption energies of both systems were positive, it indicates that the systems are unstable. On the contrary, the adsorption energies of Cl2 and CO upon adsorption on Fe- and Co-doped g-GaN were negative and small, and the adsorption system is stable. By analyzing the properties of the density of states, charge density difference, and energy band structure, it can be concluded that the introduction of transition metal atoms can effectively enhance the interaction between gas molecules and g-GaN.
The adsorption behaviors of intrinsic graphene-like GaN (g-GaN) and transition metal (TM) atom-doped g-GaN on Cl2 and CO gas molecules were systematically investigated using first-principles calculations based on density functional theory. The results show that the adsorption of both Cl2 and CO on the intrinsic g-GaN was physisorbed, and since the adsorption energies of both systems were positive, it indicates that the systems are unstable. On the contrary, the adsorption energies of Cl2 and CO upon adsorption on Fe- and Co-doped g-GaN were negative and small, and the adsorption system is stable. By analyzing the properties of the density of states, charge density difference, and energy band structure, it can be concluded that the introduction of transition metal atoms can effectively enhance the interaction between gas molecules and g-GaN.
2024, 40(6): 1201-1208
doi: 10.11862/CJIC.20230478
Abstract:
To explore the diversity of structure and optoelectronic applications of metal chalcogenide cluster materials, two Sb-based chalcogenide cluster compounds [Sb4S5(S3)]·C5H11N (1) and (C5H12N)2[In2Sb2S7] (2) have been synthesized through solvothermal method using asymmetric coordination geometry with Sb(Ⅲ) containing lone pair electrons and sulfur. The two compounds consist of combinations between {SbS3} or {InS4} coordination units in a vertex-sharing manner, respectively. The electrocatalytic oxygen reduction reaction (ORR) studies showed that the limit current density and half-wave potential of compound 2 were higher than those of compound 1, indicating better ORR performance. The Koutecky-Levich plot analysis showed that the ORR catalytic process of layered compound 2 constructed from mixed metals is mainly through a four-electron pathway.
To explore the diversity of structure and optoelectronic applications of metal chalcogenide cluster materials, two Sb-based chalcogenide cluster compounds [Sb4S5(S3)]·C5H11N (1) and (C5H12N)2[In2Sb2S7] (2) have been synthesized through solvothermal method using asymmetric coordination geometry with Sb(Ⅲ) containing lone pair electrons and sulfur. The two compounds consist of combinations between {SbS3} or {InS4} coordination units in a vertex-sharing manner, respectively. The electrocatalytic oxygen reduction reaction (ORR) studies showed that the limit current density and half-wave potential of compound 2 were higher than those of compound 1, indicating better ORR performance. The Koutecky-Levich plot analysis showed that the ORR catalytic process of layered compound 2 constructed from mixed metals is mainly through a four-electron pathway.
2024, 40(6): 1209-1217
doi: 10.11862/CJIC.20230423
Abstract:
Common algae kelp in aquaculture was utilized as a raw material and synthesized biomass carbon dots through a green, convenient, and efficient hydrothermal method. This approach ensures environmentally friendly and pollution-free production from raw material selection to material synthesis. Zebrafish model organisms were selected as research objects to explore the fluorescence imaging and metabolism of different concentrations of carbon dots during the development of zebrafish embryos. Furthermore, the effect of carbon dots on zebrafish embryo development including hatching rate, heart rate, and survival rate of adult fish were studied to evaluate kelp-derived carbon dots' biosafety.
Common algae kelp in aquaculture was utilized as a raw material and synthesized biomass carbon dots through a green, convenient, and efficient hydrothermal method. This approach ensures environmentally friendly and pollution-free production from raw material selection to material synthesis. Zebrafish model organisms were selected as research objects to explore the fluorescence imaging and metabolism of different concentrations of carbon dots during the development of zebrafish embryos. Furthermore, the effect of carbon dots on zebrafish embryo development including hatching rate, heart rate, and survival rate of adult fish were studied to evaluate kelp-derived carbon dots' biosafety.
2024, 40(6): 1218-1232
doi: 10.11862/CJIC.20230412
Abstract:
To reduce the "shuttle effects" of lithium polysulfides (LIPs) and the lithium dendrites in Li-S batteries, the separator modified by hollow carbon material was prepared by the simple scraping method. It can be found from the contact angle tests that the layers formed by the porous carbon of uniform width exhibited both stronger attractions to LIPs and better permeability of electrolytes than the bare polypropylene (PP) separator. Permeation tests further showed an effective block over LIPs by the modification layers. Cathode symmetrical batteries with Celgard 3501 separator were assembled and the current response tests implied a conversion of LIPs to Li2S catalyzed by hollow carbon materials. Lithium symmetrical batteries with modified separators were assembled and the voltage-time profile of charge-discharge processes showed better stability owing to the prevention of lithium dendrites. The Li-S batteries were assembled with sulfur loading of 1.8-2.0 mg·cm-2 and with the bare PP, single-side modified, and double-side modified separators. Calculations of the diffusion coefficient of lithium-ion from galvanostatic intermittent titration technique (GITT) tests and Nyquist plots both indicated the faster ion transportation for the modified separators. Smaller semicircles for impedance were also found in the plots. Nyquist plots after the 1st, 5th, 10th, 50th, and 100th cycles were analyzed to show a stable diffusion behavior of lithium ions, which should be caused by the multichannel from hollow carbon material to provide more paths for Li+ ion transportation. Li-S batteries with double-side modified separators presented a high specific capacity of 1 035 mAh·g-1 in the first cycle and 500 mAh·g-1 after 700 cycles at the current density of 0.2C, 630 mAh·g-1 after 100 cycles at 1C, and 505 mAh·g-1 after 100 cycles at 2C. The rate performance also behaved superior to the cells with bare PP as the separator. The cell assembled with higher sulfur content (3.2 mg·cm-2) also presented the reverse specific capacity of 500 mAh·g-1 at 0.2C. These battery performances could be ascribed to the porous hollow carbon materials for their adsorption and conversion of LIPs and their prevention of dendrites. Thus, the physicochemical interaction between hollow carbon and LIPs effectively alleviates the shuttle effect and the bifunctional modification of the separator could prevent the growth of lithium dendrites to improve the safety of the Li-S batteries.
To reduce the "shuttle effects" of lithium polysulfides (LIPs) and the lithium dendrites in Li-S batteries, the separator modified by hollow carbon material was prepared by the simple scraping method. It can be found from the contact angle tests that the layers formed by the porous carbon of uniform width exhibited both stronger attractions to LIPs and better permeability of electrolytes than the bare polypropylene (PP) separator. Permeation tests further showed an effective block over LIPs by the modification layers. Cathode symmetrical batteries with Celgard 3501 separator were assembled and the current response tests implied a conversion of LIPs to Li2S catalyzed by hollow carbon materials. Lithium symmetrical batteries with modified separators were assembled and the voltage-time profile of charge-discharge processes showed better stability owing to the prevention of lithium dendrites. The Li-S batteries were assembled with sulfur loading of 1.8-2.0 mg·cm-2 and with the bare PP, single-side modified, and double-side modified separators. Calculations of the diffusion coefficient of lithium-ion from galvanostatic intermittent titration technique (GITT) tests and Nyquist plots both indicated the faster ion transportation for the modified separators. Smaller semicircles for impedance were also found in the plots. Nyquist plots after the 1st, 5th, 10th, 50th, and 100th cycles were analyzed to show a stable diffusion behavior of lithium ions, which should be caused by the multichannel from hollow carbon material to provide more paths for Li+ ion transportation. Li-S batteries with double-side modified separators presented a high specific capacity of 1 035 mAh·g-1 in the first cycle and 500 mAh·g-1 after 700 cycles at the current density of 0.2C, 630 mAh·g-1 after 100 cycles at 1C, and 505 mAh·g-1 after 100 cycles at 2C. The rate performance also behaved superior to the cells with bare PP as the separator. The cell assembled with higher sulfur content (3.2 mg·cm-2) also presented the reverse specific capacity of 500 mAh·g-1 at 0.2C. These battery performances could be ascribed to the porous hollow carbon materials for their adsorption and conversion of LIPs and their prevention of dendrites. Thus, the physicochemical interaction between hollow carbon and LIPs effectively alleviates the shuttle effect and the bifunctional modification of the separator could prevent the growth of lithium dendrites to improve the safety of the Li-S batteries.
