This research is aimed at preparing nano （WO3：Sn） thin film, so that manufacturing anode electrode for a cell electrolysis to produce hydrogen fuel, this thin film was prepared on glass substrates by using depositi...This research is aimed at preparing nano （WO3：Sn） thin film, so that manufacturing anode electrode for a cell electrolysis to produce hydrogen fuel, this thin film was prepared on glass substrates by using deposition laser pulse （LPD） technique have been studying optical properties through the spectra of absorbance and transmittance, was determine the optical energy gap was observed that the permeability increases with the wavelength found that these films have high transmittance in the visible spectral region. The allowed direct band gap was found to increase from （2.9 eV） structured characteristics was studied through the analysis of X-ray diffraction （XRD） of the prepared film for determining the yielding phase which are to set the with standard tables. Also, the sample was tested atomic force microscope to identify the roughness of prepared films surface, and has been the study of the volume of gas output voltages with change, time and current.展开更多
A simple, cost effective and rapid electrochemical method has been developed for the determination of micro level ortho nitrobenzaldehyde（ONB） based on outstanding properties of modified aluminum electrode tin nanor...A simple, cost effective and rapid electrochemical method has been developed for the determination of micro level ortho nitrobenzaldehyde（ONB） based on outstanding properties of modified aluminum electrode tin nanorods/anodic aluminum oxide/aluminum（SnNR/AAO/Al） for the first time. The SnNR/AAO/Al electrode was fabricated by a second step anodization, followed by electrodeposition and its electrochemical behavior was investigated in detail. The cyclic voltammetry results indicated that the SnNR/AAO/Al electrode exhibited efficient electrocatalytic activity toward reduction of ONB in the acidic solution. It provides an appreciable improvement of reduction peak for ONB at-0.721 V.Furthermore, various kinetic parameters such as transfer electron number, transfer proton number and standard heterogeneous rate constant were calculated from the scan rates.The electrocatalytic behavior was further exploited as a sensitive detection scheme for the ONB determination by differential pulse voltammetry. Under the optimized conditions, the concentration range and detection limit are 0.1-100 μmol/L and 0.05 μmol/L, respectively,for ONB. The analytical performance of this modified sensor has been evaluated for detection of real sample such as river water and recovery of ONB was achieved all-out up to102.3% under standard addition method.展开更多
Silicon nanowires(SiNWs)have been used in a wide variety of applications over the past few decades due to their excellent material properties.The only drawback is the high production cost of SiNWs.The preparation of S...Silicon nanowires(SiNWs)have been used in a wide variety of applications over the past few decades due to their excellent material properties.The only drawback is the high production cost of SiNWs.The preparation of SiNWs from photovoltaic waste silicon(WSi)powders,which are high-volume industrial wastes,not only avoids the secondary energy consumption and environmental pollution caused by complicated recycling methods,but also realizes its high-value utilization.Herein,we present a method to rapidly convert photovoltaic WSi powders into SiNWs products.The flash heating and quenching provided by carbothermal shock induce the production of free silicon atoms from the WSi powders,which are rapidly reorganized and assembled into SiNWs during the vapor-phase process.This method allows for the one-step composite of SiNWs and carbon cloth(CC)and the formation of SiC at the interface of the silicon(Si)and carbon(C)contact to create a stable chemical connection.The obtained SiNWs-CC(SiNWs@CC)composites can be directly used as lithium anodes,exhibiting high initial coulombic efficiency(86.4%)and stable cycling specific capacity(2437.4 mA h g^(-1)at 0.5 A g^(-1)after 165 cycles).In addition,various SiNWs@C composite electrodes are easily prepared using this method.展开更多
Hierarchical porous ZnMn_(2)O_(4) microspheres assembled by nanosheets with an average thickness of several nanometers are successfully synthesized by a facile hydrothermal method and subsequent calcination at 500℃ i...Hierarchical porous ZnMn_(2)O_(4) microspheres assembled by nanosheets with an average thickness of several nanometers are successfully synthesized by a facile hydrothermal method and subsequent calcination at 500℃ in air.When used as an anode electrode of lithium ion batteries(LIBs),the ZnMn_(2)O_(4) microspheres exhibit a high discharge capacity of 1132 mA h g^(−1) after 500 cycles at a current density of 500 mA g^(−1) and excellent rate capability.It is believed that the outstanding electrochemical performance benefits from the hierarchical porous structure that can not only increase the contact area between the electrode and the electrolyte to facilitate the transfer of Li+ions,but also provide sufficient space for volume expansion of the electrode during the cycling process.展开更多
By leveraging the intrinsic advantages of electrical conductivity,enhancedπ-electron transfer,synergistic active sites,tunable electronic structures,and improved stability,a butterfly-shaped conjugatedπ-d copper-cat...By leveraging the intrinsic advantages of electrical conductivity,enhancedπ-electron transfer,synergistic active sites,tunable electronic structures,and improved stability,a butterfly-shaped conjugatedπ-d copper-catecholate-based metal-organic framework(Cu-DBC MOF),is constructed and delivered as a novel anodic electrode for lithium-ion batteries.The uniqueπ-d conjugation between copper ions and catecholate ligands in Cu-DBC significantly enhances its electrical conductivity and facilitates lithium-ion transport,addressing key limitations of conventional MOF-based anodes.As a result,Cu-DBC demonstrates exceptional electrochemical behavior,achieving a reversible capacity of 550 mAh g^(-1)within 100 mA g^(-1),showcasing excellent rate-capability properties with 192 mAh g^(-1)under 1000 mA g^(-1),and maintaining prolonged cycling stability,delivering 410±10 mAh g^(-1)after 100 cycles within 100 mA g^(-1)and 170±10 mAh g^(-1)after 2500 cycles even under 1000 mA g^(-1),respectively,based on the lithiation-delithiation reactions involving both redox reactions of Cu^(2+)/Cu^(+)and[Cu(OR)_(4)]^(3-)/[Cu(OR)_(4)]^(2-)couples.展开更多
The Hall-Héroult process is used for alumina reduction by the use of graphite anodes even though it involves a high emission of carbon dioxide (CO2) and several other organic compounds. Proposals have been made a...The Hall-Héroult process is used for alumina reduction by the use of graphite anodes even though it involves a high emission of carbon dioxide (CO2) and several other organic compounds. Proposals have been made aiming at substituting graphite for a single-phase SnO2-based ceramic with low resistivity and chemical resistance to cryolite, which is characterized as an inconsumable anode, reducing pollutant emissions. To this end, a wide range of studies were carried out on SnO2-based ceramics modified with ZnO as a densification aid doped with the promoters of electrical conductivity such as Nb2O5, Al2O3 and Sb2O3 through a mixture of oxides and hybrid sintering in a microwave oven. The pressed pellets were sintered in a microwave oven up to 1050℃ under a constant heating rate of 10℃/min. After sintering, the density was determined by the Archimedes method, the phases were then characterized by X-ray diffraction, the microstructure and chemical composition resulting from the sintered SnO2-based ceramics were also investigated by field emission scanning electron microscopy (FE-SEM) coupled with an energy-dispersive X-ray spectroscopy (EDS) and the electrical properties were determined by the measurements of the electric field x current density. A single-phase ceramic was obtained with a relative density of above 90% and electrical resistivity of 6.1 Ω·cm at room temperature. The ceramics obtained in this study could be a potential candidate as an inconsumable anode to replace the current fused coke used in the reduction of alumina.展开更多
Transition metal selenides have been considered as prospective anode materials for advanced lithium-ion batteries due to the features of high theoretical capacity,environmentally friendly and abundant resource reserve...Transition metal selenides have been considered as prospective anode materials for advanced lithium-ion batteries due to the features of high theoretical capacity,environmentally friendly and abundant resource reserves.Nevertheless,the long-term cycling stability property is limited owing to electrode structure disruption caused by huge volume expansion during cycling and the poor rate capability results from their poor intrinsic conductivity.Herein,the hollow selenium/ferromanganese selenide nanospheres(Se/MnFe_(2)Se_(4)) were synthesized via a SiO_(2)-assisted template method,which was decorated with 3D porous graphene aerogel with satisfactory structure and mechanical properties,forming the Se/MnFe_(2)Se_(4)/rGO composites.The prepared composites offered multiple advantages for enhancing lithium storage.First,hollow nanospheres can reduce ion/electron diffusion pathways,widen the surface area,and alleviate partial volume expansion.Meanwhile,Se was introduced into the composites to improve their conductivity and provided extra capacity by participating in the charging/discharging process.Besides,3D porous graphene aerogels(rGO) provided more active sites,which improved the conductivity,shortened the transport path of ions and electrons,and effectively alleviated the stress concentration due to volume changes.The Se/MnFe_(2)Se_(4)/rGO composites showed stable cycling performance of 961.3 mAh g^(-1) at 0.1 A g^(-1)after 200 cycles and 638.7 mAh g^(-1) at 1.0 A g^(-1) after 2500 cycles.This work provided a novel anode electrode with a satisfactory electrochemical performance improvement strategy,which would promote the development of high-performance LIBs and other energy storage devices.展开更多
文摘This research is aimed at preparing nano （WO3：Sn） thin film, so that manufacturing anode electrode for a cell electrolysis to produce hydrogen fuel, this thin film was prepared on glass substrates by using deposition laser pulse （LPD） technique have been studying optical properties through the spectra of absorbance and transmittance, was determine the optical energy gap was observed that the permeability increases with the wavelength found that these films have high transmittance in the visible spectral region. The allowed direct band gap was found to increase from （2.9 eV） structured characteristics was studied through the analysis of X-ray diffraction （XRD） of the prepared film for determining the yielding phase which are to set the with standard tables. Also, the sample was tested atomic force microscope to identify the roughness of prepared films surface, and has been the study of the volume of gas output voltages with change, time and current.
基金CSIR (09/0810 (0021)/ 2012-EMR-I), Periyar University for providing fundUGC networking resource center for providing visiting fellowship
文摘A simple, cost effective and rapid electrochemical method has been developed for the determination of micro level ortho nitrobenzaldehyde（ONB） based on outstanding properties of modified aluminum electrode tin nanorods/anodic aluminum oxide/aluminum（SnNR/AAO/Al） for the first time. The SnNR/AAO/Al electrode was fabricated by a second step anodization, followed by electrodeposition and its electrochemical behavior was investigated in detail. The cyclic voltammetry results indicated that the SnNR/AAO/Al electrode exhibited efficient electrocatalytic activity toward reduction of ONB in the acidic solution. It provides an appreciable improvement of reduction peak for ONB at-0.721 V.Furthermore, various kinetic parameters such as transfer electron number, transfer proton number and standard heterogeneous rate constant were calculated from the scan rates.The electrocatalytic behavior was further exploited as a sensitive detection scheme for the ONB determination by differential pulse voltammetry. Under the optimized conditions, the concentration range and detection limit are 0.1-100 μmol/L and 0.05 μmol/L, respectively,for ONB. The analytical performance of this modified sensor has been evaluated for detection of real sample such as river water and recovery of ONB was achieved all-out up to102.3% under standard addition method.
基金partially funded by the National Natural Science Foundation of China(52074255,52274412)。
文摘Silicon nanowires(SiNWs)have been used in a wide variety of applications over the past few decades due to their excellent material properties.The only drawback is the high production cost of SiNWs.The preparation of SiNWs from photovoltaic waste silicon(WSi)powders,which are high-volume industrial wastes,not only avoids the secondary energy consumption and environmental pollution caused by complicated recycling methods,but also realizes its high-value utilization.Herein,we present a method to rapidly convert photovoltaic WSi powders into SiNWs products.The flash heating and quenching provided by carbothermal shock induce the production of free silicon atoms from the WSi powders,which are rapidly reorganized and assembled into SiNWs during the vapor-phase process.This method allows for the one-step composite of SiNWs and carbon cloth(CC)and the formation of SiC at the interface of the silicon(Si)and carbon(C)contact to create a stable chemical connection.The obtained SiNWs-CC(SiNWs@CC)composites can be directly used as lithium anodes,exhibiting high initial coulombic efficiency(86.4%)and stable cycling specific capacity(2437.4 mA h g^(-1)at 0.5 A g^(-1)after 165 cycles).In addition,various SiNWs@C composite electrodes are easily prepared using this method.
基金supported by the National Basic Research Program of China(973 Program)(2013CB934001).
文摘Hierarchical porous ZnMn_(2)O_(4) microspheres assembled by nanosheets with an average thickness of several nanometers are successfully synthesized by a facile hydrothermal method and subsequent calcination at 500℃ in air.When used as an anode electrode of lithium ion batteries(LIBs),the ZnMn_(2)O_(4) microspheres exhibit a high discharge capacity of 1132 mA h g^(−1) after 500 cycles at a current density of 500 mA g^(−1) and excellent rate capability.It is believed that the outstanding electrochemical performance benefits from the hierarchical porous structure that can not only increase the contact area between the electrode and the electrolyte to facilitate the transfer of Li+ions,but also provide sufficient space for volume expansion of the electrode during the cycling process.
基金supported by the Foundation of Sichuan University of Science&Engineering(2023RC02 and 202510622030)support from the National Natural Science Foundation of China(62304148)+4 种基金the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(22KJB150037)National Natural Science Foundation of China(22279061)the Natural Science Foundation of Jiangsu Province(BK20180514)support from City University of Hong Kong(9380117,7005620 and 7020040)Hong Kong Institute for Advanced Study,City University of Hong Kong,Hong Kong,P.R.China。
文摘By leveraging the intrinsic advantages of electrical conductivity,enhancedπ-electron transfer,synergistic active sites,tunable electronic structures,and improved stability,a butterfly-shaped conjugatedπ-d copper-catecholate-based metal-organic framework(Cu-DBC MOF),is constructed and delivered as a novel anodic electrode for lithium-ion batteries.The uniqueπ-d conjugation between copper ions and catecholate ligands in Cu-DBC significantly enhances its electrical conductivity and facilitates lithium-ion transport,addressing key limitations of conventional MOF-based anodes.As a result,Cu-DBC demonstrates exceptional electrochemical behavior,achieving a reversible capacity of 550 mAh g^(-1)within 100 mA g^(-1),showcasing excellent rate-capability properties with 192 mAh g^(-1)under 1000 mA g^(-1),and maintaining prolonged cycling stability,delivering 410±10 mAh g^(-1)after 100 cycles within 100 mA g^(-1)and 170±10 mAh g^(-1)after 2500 cycles even under 1000 mA g^(-1),respectively,based on the lithiation-delithiation reactions involving both redox reactions of Cu^(2+)/Cu^(+)and[Cu(OR)_(4)]^(3-)/[Cu(OR)_(4)]^(2-)couples.
基金the financial support granted by the Brazilian research funding institutions CNPq,CAPES and FAPESP.
文摘The Hall-Héroult process is used for alumina reduction by the use of graphite anodes even though it involves a high emission of carbon dioxide (CO2) and several other organic compounds. Proposals have been made aiming at substituting graphite for a single-phase SnO2-based ceramic with low resistivity and chemical resistance to cryolite, which is characterized as an inconsumable anode, reducing pollutant emissions. To this end, a wide range of studies were carried out on SnO2-based ceramics modified with ZnO as a densification aid doped with the promoters of electrical conductivity such as Nb2O5, Al2O3 and Sb2O3 through a mixture of oxides and hybrid sintering in a microwave oven. The pressed pellets were sintered in a microwave oven up to 1050℃ under a constant heating rate of 10℃/min. After sintering, the density was determined by the Archimedes method, the phases were then characterized by X-ray diffraction, the microstructure and chemical composition resulting from the sintered SnO2-based ceramics were also investigated by field emission scanning electron microscopy (FE-SEM) coupled with an energy-dispersive X-ray spectroscopy (EDS) and the electrical properties were determined by the measurements of the electric field x current density. A single-phase ceramic was obtained with a relative density of above 90% and electrical resistivity of 6.1 Ω·cm at room temperature. The ceramics obtained in this study could be a potential candidate as an inconsumable anode to replace the current fused coke used in the reduction of alumina.
基金financially supported by the National Natural Science Foundation of China(Nos.52572325,52207249 and 52472131)Shandong Provincial Natural Science Foundation(No.ZR2025QB33)+1 种基金the Excellent Youth Innovation Team Project for Higher Education Institutions of Shandong Province(No.2023KJ238)the Science Fund of Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai(No.AMGM2024F27)
文摘Transition metal selenides have been considered as prospective anode materials for advanced lithium-ion batteries due to the features of high theoretical capacity,environmentally friendly and abundant resource reserves.Nevertheless,the long-term cycling stability property is limited owing to electrode structure disruption caused by huge volume expansion during cycling and the poor rate capability results from their poor intrinsic conductivity.Herein,the hollow selenium/ferromanganese selenide nanospheres(Se/MnFe_(2)Se_(4)) were synthesized via a SiO_(2)-assisted template method,which was decorated with 3D porous graphene aerogel with satisfactory structure and mechanical properties,forming the Se/MnFe_(2)Se_(4)/rGO composites.The prepared composites offered multiple advantages for enhancing lithium storage.First,hollow nanospheres can reduce ion/electron diffusion pathways,widen the surface area,and alleviate partial volume expansion.Meanwhile,Se was introduced into the composites to improve their conductivity and provided extra capacity by participating in the charging/discharging process.Besides,3D porous graphene aerogels(rGO) provided more active sites,which improved the conductivity,shortened the transport path of ions and electrons,and effectively alleviated the stress concentration due to volume changes.The Se/MnFe_(2)Se_(4)/rGO composites showed stable cycling performance of 961.3 mAh g^(-1) at 0.1 A g^(-1)after 200 cycles and 638.7 mAh g^(-1) at 1.0 A g^(-1) after 2500 cycles.This work provided a novel anode electrode with a satisfactory electrochemical performance improvement strategy,which would promote the development of high-performance LIBs and other energy storage devices.
