采用溶胶-凝胶法制备Ti/Sn O_2-F电极,进行全氟辛酸(PFOA)电氧化降解的研究,实验考察了F替代Sb掺杂、电流密度、初始pH值和支持电解质对PFOA降解效率的影响。结果表明,当F替代Sb掺杂Sn O_2,电流密度为20 m A/cm^2,初始pH值3.7,支持电解...采用溶胶-凝胶法制备Ti/Sn O_2-F电极,进行全氟辛酸(PFOA)电氧化降解的研究,实验考察了F替代Sb掺杂、电流密度、初始pH值和支持电解质对PFOA降解效率的影响。结果表明,当F替代Sb掺杂Sn O_2,电流密度为20 m A/cm^2,初始pH值3.7,支持电解质为NaClO_4时,电解30 min后PFOA的降解率达98%。采用液相色谱-质谱联用(HPLC-MS/MS)和离子色谱(IC)对PFOA降解产物进行分析,解析了PFOA电氧化降解的反应机理。展开更多
A series of TiO2-SnO2 nano-sized composite photo-catalysts containing Sn(9.3%-30.1%)were prepared from TiCl4and SnCl4·5H2O by using sol-gel,supercritical fluid dry and solid-phase reaction(SCFD)combination ...A series of TiO2-SnO2 nano-sized composite photo-catalysts containing Sn(9.3%-30.1%)were prepared from TiCl4and SnCl4·5H2O by using sol-gel,supercritical fluid dry and solid-phase reaction(SCFD)combination technology.Characterizations with X-ray diffraction(XRD),transmission electron microscopy(TEM)and Fourier Transform Infrared Spectroscopy(FTIR)showed that,in addition to anatase type TiO2,a new active phase(Ti,Sn)O2(with particle size of 2.0-4.3 nm)formed,and there were no SnO2 crystals observed in the range of the doping concentration studied.Photo-catalytic reaction of phenol was used as a model reaction to evaluate the catalytic activities of the obtained catalysts.Compared with pure TiO2 or Ti-Sn catalyst prepared with general sol-gel method,Ti-Sn nano-composite photo-catalyst thus obtained showed significant improvement in catalytic activity.The photo-catalytic degradation rate of phenol could reach as high as 93.5%after 7 h.The preparation conditions of the new phase(Ti,Sn)O2 were investigated and its catalytic mechanism was proposed.The photo-catalytic particles prepared using SCFD combination technology exhibited small particle size,large surface area and high activity.展开更多
The humidity sensing properties of La^3+ and K^+ co-doped Ti0.9Sn0.1O2 thin films were investigated. The humidity sensitive thin films were prepared by sol-gel method on alumina substrates. The sensing behaviors of ...The humidity sensing properties of La^3+ and K^+ co-doped Ti0.9Sn0.1O2 thin films were investigated. The humidity sensitive thin films were prepared by sol-gel method on alumina substrates. The sensing behaviors of thin films were inspected at different sintering temperatures by constructing a humidity-impedance measuring system. It was found that the addition of rare earth ion La^3+ and alkali ion K^+ was beneficial for improving the humidity sensitive properties of the samples and La0.003K0.5Ti0.9Sn0.1O2 sintered at 500 ℃ for 4 h showed the best humidity sensing properties. The impedance of this thin film decreased from 109 to 104 Ω with excellent linearity in the humidity range of 11%-95%. Narrow hysteresis loop, prominent stability and high sensitivity were obtained. The effects of dopant con-tent and doping mechanism on humidity sensitivity were also discussed in terms of segregation of rare earth ions at grain boundaries and granularity of crystalline and influence of K^+ on the decrease in the intrinsic resistance of the materials, and increase in the number of wa-ter adsorption sites.展开更多
Compound Zn2Sn0.8Ti0.2O4 was synthesized by a hydrothermal method in which SnCl4-5H2O,TiCl4,ZnCl2 and N2H4-H2O were used as reactants.The composite Zn2Sn0.8Ti0.2O4/C was then prepared through a carbothermic reduction ...Compound Zn2Sn0.8Ti0.2O4 was synthesized by a hydrothermal method in which SnCl4-5H2O,TiCl4,ZnCl2 and N2H4-H2O were used as reactants.The composite Zn2Sn0.8Ti0.2O4/C was then prepared through a carbothermic reduction process using the as-prepared Zn2Sn0.8Ti0.2O4 and glucose as reactants.The structure,morphology and electrochemical properties of the as-prepared products were investigated by XRD,XPS,TEM and electrochemical measurements.In addition,electrochemical Li insertion/extraction in composite Zn2Sn0.8Ti0.2O4/C were examined by ex situ XRD and SEM.The first discharge capacity of Zn2SnO4 is about 1670.8 mA-h/g,with a capacity retain of 342.7 mA-h/g in the 40th cycle at a constant current density of 100 mA/g in the voltage range of 0.05-3.0 V.Comparing with the Zn2SnO4,some improved electrochemical properties are obtained for Zn2Sn0.8Ti0.2O4,Zn2SnO4/C and Zn2Sn0.8Ti0.2O4/C.The composite Zn2Sn0.8Ti0.2O4/C shows the best electrochemical properties,and its first discharge capacity is about 1530.0 mA-h/g,with a capacity retain of 479.1 mA-h/g the 100th cycle.展开更多
用溶胶-凝胶法合成锂离子电池用富锂正极材料Li[Li0.2Ni0.15Mn0.55Co0.1]O2,通过XRD、SEM、电感耦合等离子体发射光谱(ICP-OES)和电化学性能测试考察煅烧温度对合成材料结构和性能的影响。900℃下制备的材料具有典型的α-Na Fe O2层...用溶胶-凝胶法合成锂离子电池用富锂正极材料Li[Li0.2Ni0.15Mn0.55Co0.1]O2,通过XRD、SEM、电感耦合等离子体发射光谱(ICP-OES)和电化学性能测试考察煅烧温度对合成材料结构和性能的影响。900℃下制备的材料具有典型的α-Na Fe O2层状结构、较好的晶型结构及良好的电化学性能。在2.04.8 V充放电,20℃下的0.10 C首次放电比容量为235.4 m Ah/g,库仑效率为78.5%;依次以0.10 C、0.20 C、0.50 C、0.75 C和1.00 C循环10次,再以0.20 C放电,首次1.00 C放电比容量为149.7 m Ah/g,最后一次0.20 C放电比容量为首次0.10 C放电比容量的85.9%。展开更多
基金The authors thank the National Natural Scir nce Foun-dation of China(No.20076004)the National Development Project of High Technology(No.2001AA322030)the Doctoral Program of Higher Education(No.2000001005)for the financial support of this project.
摘要A series of TiO2-SnO2 nano-sized composite photo-catalysts containing Sn(9.3%-30.1%)were prepared from TiCl4and SnCl4·5H2O by using sol-gel,supercritical fluid dry and solid-phase reaction(SCFD)combination technology.Characterizations with X-ray diffraction(XRD),transmission electron microscopy(TEM)and Fourier Transform Infrared Spectroscopy(FTIR)showed that,in addition to anatase type TiO2,a new active phase(Ti,Sn)O2(with particle size of 2.0-4.3 nm)formed,and there were no SnO2 crystals observed in the range of the doping concentration studied.Photo-catalytic reaction of phenol was used as a model reaction to evaluate the catalytic activities of the obtained catalysts.Compared with pure TiO2 or Ti-Sn catalyst prepared with general sol-gel method,Ti-Sn nano-composite photo-catalyst thus obtained showed significant improvement in catalytic activity.The photo-catalytic degradation rate of phenol could reach as high as 93.5%after 7 h.The preparation conditions of the new phase(Ti,Sn)O2 were investigated and its catalytic mechanism was proposed.The photo-catalytic particles prepared using SCFD combination technology exhibited small particle size,large surface area and high activity.
摘要The humidity sensing properties of La^3+ and K^+ co-doped Ti0.9Sn0.1O2 thin films were investigated. The humidity sensitive thin films were prepared by sol-gel method on alumina substrates. The sensing behaviors of thin films were inspected at different sintering temperatures by constructing a humidity-impedance measuring system. It was found that the addition of rare earth ion La^3+ and alkali ion K^+ was beneficial for improving the humidity sensitive properties of the samples and La0.003K0.5Ti0.9Sn0.1O2 sintered at 500 ℃ for 4 h showed the best humidity sensing properties. The impedance of this thin film decreased from 109 to 104 Ω with excellent linearity in the humidity range of 11%-95%. Narrow hysteresis loop, prominent stability and high sensitivity were obtained. The effects of dopant con-tent and doping mechanism on humidity sensitivity were also discussed in terms of segregation of rare earth ions at grain boundaries and granularity of crystalline and influence of K^+ on the decrease in the intrinsic resistance of the materials, and increase in the number of wa-ter adsorption sites.
基金Project (51004028) supported by the National Natural Science Foundation of China
摘要Compound Zn2Sn0.8Ti0.2O4 was synthesized by a hydrothermal method in which SnCl4-5H2O,TiCl4,ZnCl2 and N2H4-H2O were used as reactants.The composite Zn2Sn0.8Ti0.2O4/C was then prepared through a carbothermic reduction process using the as-prepared Zn2Sn0.8Ti0.2O4 and glucose as reactants.The structure,morphology and electrochemical properties of the as-prepared products were investigated by XRD,XPS,TEM and electrochemical measurements.In addition,electrochemical Li insertion/extraction in composite Zn2Sn0.8Ti0.2O4/C were examined by ex situ XRD and SEM.The first discharge capacity of Zn2SnO4 is about 1670.8 mA-h/g,with a capacity retain of 342.7 mA-h/g in the 40th cycle at a constant current density of 100 mA/g in the voltage range of 0.05-3.0 V.Comparing with the Zn2SnO4,some improved electrochemical properties are obtained for Zn2Sn0.8Ti0.2O4,Zn2SnO4/C and Zn2Sn0.8Ti0.2O4/C.The composite Zn2Sn0.8Ti0.2O4/C shows the best electrochemical properties,and its first discharge capacity is about 1530.0 mA-h/g,with a capacity retain of 479.1 mA-h/g the 100th cycle.