【摘要】 为提高SiO2的质子传导能力,在硫酸介质中,以碱性的聚乙烯吡咯烷酮(PVP)为模板剂,用溶胶-凝胶法合成了高导电性的介孔SiO2(m-S-SiO2)。N2-吸附脱附结果显示,m-S-SiO2的BET比表面积为588m2/g,BJH平均孔径为6.0nm。交流阻抗测定结果显示,25℃和100%相对湿度下,水洗除去游离酸后m-S-SiO2的质子电导率高达5.9×10-2S/cm,与Nafion膜的电导率相当,比相同条件下用中性EO20PO70EO20作模板制备的介孔SiO2的高出1个数量级。在相同质子浓度下,用磷酸、盐酸和硝酸代替硫酸,以PVP为模板合成的介孔m-P-SiO2,m-Cl-SiO2和m-N-SiO2样品的电导率分别为4.3×10-2、9.9×10-4和3.0×10-4S/cm。更多还原

【Abstract】 For improving the conductivity of SiO2,mesoporous SiO2 ( m-S-SiO2 ) was synthesized by sol - gel method with alkaline polyvinyl pyrrolidone (PVP) as template in H2 SO4 medium. The BET surface area and average pore size of the sample calculated from N2 -adsorption and desorption isotherm were about 588m2 /g and 6. 0nm, respectively. The proton conductivity of the washed m-S-SiO2 ,in which unbonded acid species had been removed, measured by AC impedance technique at 25℃ under 100% RH was 5. 9 × 10 -2 S /cm,corresponding to the value of Nafion membrane and higher than that of mesoporous SiO2 synthesized with EO20 PO70 EO20 as template at the same condition. The proton conductivities of m-P-SiO2 ,m-Cl-SiO2 or m-N-SiO2 samples synthesized using PVP as template in H3 PO4 ,HCl or HNO3 medium at the same H + concentration were 4. 3 × 10 -2 ,9. 9 × 10 -4 and 3. 0 × 10 -4 S /cm, respectively.更多还原