Nafion/TiO2 composite membranes were prepared by in-situ chemical reaction method using Ti(OC4H9)4 and Nafion 117 as raw materials. The membranes were characterized by UV, FTIR-ATR and XRD, respectively. Methanol perm...Nafion/TiO2 composite membranes were prepared by in-situ chemical reaction method using Ti(OC4H9)4 and Nafion 117 as raw materials. The membranes were characterized by UV, FTIR-ATR and XRD, respectively. Methanol permeability and water uptake were investigated as a function of TiO2 contents. The conductivity of the membranes was measured under water vapor pressure (2.644 7 kPa) or in dry atmospheres. The XRD results showed that the titanium dioxide in Nafion membranes were crystallized in anatase phase with an average crys- taline diameter of 3.0 nm. The water uptake of the composite membranes was larger than that of the pure Nafion○ membrane when the TiO2 loading was within 14wt%. The methanol permeability of the membrane decreased as the TiO2 loading increased. The addition of 3wt% TiO2 to Nafion○ membranes improved the conductivity in dry measurement conditions. The proton conductivity of the composite membrane increased greatly after the hy- drothermal treatment at 160 ℃ for 2 hours.展开更多
文摘Nafion/TiO2 composite membranes were prepared by in-situ chemical reaction method using Ti(OC4H9)4 and Nafion 117 as raw materials. The membranes were characterized by UV, FTIR-ATR and XRD, respectively. Methanol permeability and water uptake were investigated as a function of TiO2 contents. The conductivity of the membranes was measured under water vapor pressure (2.644 7 kPa) or in dry atmospheres. The XRD results showed that the titanium dioxide in Nafion membranes were crystallized in anatase phase with an average crys- taline diameter of 3.0 nm. The water uptake of the composite membranes was larger than that of the pure Nafion○ membrane when the TiO2 loading was within 14wt%. The methanol permeability of the membrane decreased as the TiO2 loading increased. The addition of 3wt% TiO2 to Nafion○ membranes improved the conductivity in dry measurement conditions. The proton conductivity of the composite membrane increased greatly after the hy- drothermal treatment at 160 ℃ for 2 hours.
文摘采用溶胶-凝胶法在导电载玻片上制备均匀透明的纳米TiO2薄膜,并以此薄膜作为基体电极,在浓度为0.50 mol/L的H2SO4溶液中用恒电位法制备了TiO2-磷钨酸修饰电极,用SEM分析了不同薄膜的结构,并对其电阻率,电化学行为与光电特性进行了初步研究.实验结果表明,制备TiO2-H3PW12O40复合膜的最优化合成条件为:5.0×10-3mol/L磷钨酸(H3PW12O40)+5.0×10-3mol/L吡咯(PY)+0.5 mol/LH2SO4的混合溶液中于1.4 V恒电压下电沉积60 m in.
