In this study,the electrochemical oxidation of reactive brilliant orange X-GN dye with a boron-doped diamond(BDD)anode was investigated.The BDD electrodes were deposited on the niobium(Nb)substrates by the hot filamen...In this study,the electrochemical oxidation of reactive brilliant orange X-GN dye with a boron-doped diamond(BDD)anode was investigated.The BDD electrodes were deposited on the niobium(Nb)substrates by the hot filament chemical vapor deposition method.The effects of processing parameters,such as film thickness,current density,supporting electrolyte concentration,initial solution pH,solution temperature,and initial dye concentration,were evaluated following the variation in the degradation efficiency.The microstructure and the electrochemical property of BDD were characterized by scanning electron microscopy,Raman spectroscopy,and electrochemical workstation;and the degradation of X-GN was estimated using UV-Vis spectrophotometry.Further,the results indicated that the film thickness of BDD had a significant impact on the electrolysis of X-GN.After 3 h of treatment,100%color and 63.2%total organic carbon removal was achieved under optimized experimental conditions:current density of 100 mA/cm2,supporting electrolyte concentration of 0.05 mol/L,initial solution pH 3.08,and solution temperature of 60°C.展开更多
The electrochemical treatment of wastewater containing chlorophenols （2-monochlorophenol, 4-monochlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol） was carried out experimentally with synthetic boron-d0ped diam...The electrochemical treatment of wastewater containing chlorophenols （2-monochlorophenol, 4-monochlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol） was carried out experimentally with synthetic boron-d0ped diamond （BDD） thin film electrodes. Current vs time curves under different cell voltages were measured. Removal rate of COD, instant current efficiency （ICE） and energy consumption were investigated under different current densities. The influence of supporting media is reported, which plays an important role in determining the global oxidation rate. The oxidative chloride is stronger than peroxodisulphate. The electrochemical characteristics of boron-doped diamond electrodes were investigated in comparison with active coating Ti substrate anode （ACT）. The experimental results show that BDD is markedly superior to ACT due to its different absorption properties.展开更多
Nitrogen doping in chemical vapor deposition-derived ultrananocrystalline diamond(UNCD)films in-creases the electronic conductivity,yet its microstructural effects on electron transport are insufficiently understood.W...Nitrogen doping in chemical vapor deposition-derived ultrananocrystalline diamond(UNCD)films in-creases the electronic conductivity,yet its microstructural effects on electron transport are insufficiently understood.We investigated the formation of nitrogen-induced diaph-ite structures(hybrid diamond-graphite phases)and their role in changing the conductivity.Nitrogen doping in a hy-drogen-rich plasma environment promotes the emergence of unique sp^(3)-sp^(2)bonding interfaces,where diamond grains are covalently integrated with graphitic domains,facilitating a structure-driven electronic transition.High-resolution transmis-sion electron microscopy and selected area electron diffraction reveal five-fold,six-fold and twelve-fold symmetries,along with an atypical{200}crystallographic reflection,confirming diaphite formation in 5%and 10%N-doped UNCD films,while high-er doping levels(15%and 20%)result in extensive graphitization.Raman spectroscopy tracks the evolution of sp^(2)bonding with increasing nitrogen content,while atomic force microscopy and X-ray diffraction indicate a consistent diamond grain size of~8 nm.Cryogenic electronic transport measurements reveal a conductivity increase from 8.72 to 708 S/cm as the nitrogen dop-ing level increases from 5%to 20%,which is attributed to defect-mediated carrier transport and 3D weak localization.The res-ulting conductivity is three orders of magnitude higher than previously reported.These findings establish a direct correlation between diaphite structural polymorphism and tunable electronic properties in nitrogen-doped UNCD films,offering new ways for defect-engineering diamond-based electronic materials.展开更多
Lonsdaleite,also known as hexagonal diamond,is an allotrope of carbon with a hexagonal crystal structure,which was discovered in the nanostructure of the Canyon Diablo meteorite.Theoretical calculations have shown tha...Lonsdaleite,also known as hexagonal diamond,is an allotrope of carbon with a hexagonal crystal structure,which was discovered in the nanostructure of the Canyon Diablo meteorite.Theoretical calculations have shown that this structure gives it exceptional physical properties that exceed those of cubic diamond,making it highly promising for groundbreaking applications in superhard cutting tools,wide-bandgap semiconductor devices,and materials for extreme environments.As a result,the controllable synthesis of hexagonal diamond has emerged as a cutting-edge research focus in materials science.This review briefly outlines the progress in this area,with a focus on the mechanisms governing its key synthesis conditions,its intrinsic physical properties,and its potential applications in various fields.展开更多
Diamond combines many unique properties,including high stability,strong optical dispersion,excellent mechanical strength,and outstanding thermal conductivity.Its structure,surface groups,and electrical conductivity ar...Diamond combines many unique properties,including high stability,strong optical dispersion,excellent mechanical strength,and outstanding thermal conductivity.Its structure,surface groups,and electrical conductivity are also tunable,increasing its functional versatility.These make diamond and its related materials,such as its composites,highly promising for various applications in energy fields.This review summarizes recent advances and key achievements in energy storage and conversion,covering electrochemical energy storage(e.g.,batteries and supercapacitors),electrocatalytic energy conversion(e.g.,CO_(2)and nitrogen reduction reactions),and solar energy conversion(e.g.,photo-(electro)chemical CO_(2)and nitrogen reduction reactions,and solar cells).Current challenges and prospects related to the synthesis of diamond materials and the technologies for their energy applications are outlined and discussed.展开更多
基金Project(2016YEB0301402) supported by the National Key Research and Development Program of ChinaProject(51601226) supported by the National Natural Science Foundation of China+1 种基金Project supported by the Open-End Fund for the Valuable and Precision Instruments of Central South University,ChinaProject supported by State Key Laboratory of Powder Metallurgy,China
文摘In this study,the electrochemical oxidation of reactive brilliant orange X-GN dye with a boron-doped diamond(BDD)anode was investigated.The BDD electrodes were deposited on the niobium(Nb)substrates by the hot filament chemical vapor deposition method.The effects of processing parameters,such as film thickness,current density,supporting electrolyte concentration,initial solution pH,solution temperature,and initial dye concentration,were evaluated following the variation in the degradation efficiency.The microstructure and the electrochemical property of BDD were characterized by scanning electron microscopy,Raman spectroscopy,and electrochemical workstation;and the degradation of X-GN was estimated using UV-Vis spectrophotometry.Further,the results indicated that the film thickness of BDD had a significant impact on the electrolysis of X-GN.After 3 h of treatment,100%color and 63.2%total organic carbon removal was achieved under optimized experimental conditions:current density of 100 mA/cm2,supporting electrolyte concentration of 0.05 mol/L,initial solution pH 3.08,and solution temperature of 60°C.
基金Project(20113282241450) supported by the Science and Technology Program from Ministry of Transport of China
文摘The electrochemical treatment of wastewater containing chlorophenols （2-monochlorophenol, 4-monochlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol） was carried out experimentally with synthetic boron-d0ped diamond （BDD） thin film electrodes. Current vs time curves under different cell voltages were measured. Removal rate of COD, instant current efficiency （ICE） and energy consumption were investigated under different current densities. The influence of supporting media is reported, which plays an important role in determining the global oxidation rate. The oxidative chloride is stronger than peroxodisulphate. The electrochemical characteristics of boron-doped diamond electrodes were investigated in comparison with active coating Ti substrate anode （ACT）. The experimental results show that BDD is markedly superior to ACT due to its different absorption properties.
文摘Nitrogen doping in chemical vapor deposition-derived ultrananocrystalline diamond(UNCD)films in-creases the electronic conductivity,yet its microstructural effects on electron transport are insufficiently understood.We investigated the formation of nitrogen-induced diaph-ite structures(hybrid diamond-graphite phases)and their role in changing the conductivity.Nitrogen doping in a hy-drogen-rich plasma environment promotes the emergence of unique sp^(3)-sp^(2)bonding interfaces,where diamond grains are covalently integrated with graphitic domains,facilitating a structure-driven electronic transition.High-resolution transmis-sion electron microscopy and selected area electron diffraction reveal five-fold,six-fold and twelve-fold symmetries,along with an atypical{200}crystallographic reflection,confirming diaphite formation in 5%and 10%N-doped UNCD films,while high-er doping levels(15%and 20%)result in extensive graphitization.Raman spectroscopy tracks the evolution of sp^(2)bonding with increasing nitrogen content,while atomic force microscopy and X-ray diffraction indicate a consistent diamond grain size of~8 nm.Cryogenic electronic transport measurements reveal a conductivity increase from 8.72 to 708 S/cm as the nitrogen dop-ing level increases from 5%to 20%,which is attributed to defect-mediated carrier transport and 3D weak localization.The res-ulting conductivity is three orders of magnitude higher than previously reported.These findings establish a direct correlation between diaphite structural polymorphism and tunable electronic properties in nitrogen-doped UNCD films,offering new ways for defect-engineering diamond-based electronic materials.
基金the National Natural Science Foundation of China(12274170 and 52225203)。
文摘Lonsdaleite,also known as hexagonal diamond,is an allotrope of carbon with a hexagonal crystal structure,which was discovered in the nanostructure of the Canyon Diablo meteorite.Theoretical calculations have shown that this structure gives it exceptional physical properties that exceed those of cubic diamond,making it highly promising for groundbreaking applications in superhard cutting tools,wide-bandgap semiconductor devices,and materials for extreme environments.As a result,the controllable synthesis of hexagonal diamond has emerged as a cutting-edge research focus in materials science.This review briefly outlines the progress in this area,with a focus on the mechanisms governing its key synthesis conditions,its intrinsic physical properties,and its potential applications in various fields.
基金西南大学中央高校基本科研业务费项目(SWU-KT22030)重庆市教育委员会科学技术研究项目(KJQN202300205)Deutsche Forschungsgemeinschaft(DFG,German Research Foundation,457444676).
文摘Diamond combines many unique properties,including high stability,strong optical dispersion,excellent mechanical strength,and outstanding thermal conductivity.Its structure,surface groups,and electrical conductivity are also tunable,increasing its functional versatility.These make diamond and its related materials,such as its composites,highly promising for various applications in energy fields.This review summarizes recent advances and key achievements in energy storage and conversion,covering electrochemical energy storage(e.g.,batteries and supercapacitors),electrocatalytic energy conversion(e.g.,CO_(2)and nitrogen reduction reactions),and solar energy conversion(e.g.,photo-(electro)chemical CO_(2)and nitrogen reduction reactions,and solar cells).Current challenges and prospects related to the synthesis of diamond materials and the technologies for their energy applications are outlined and discussed.
