基于溶胶-凝胶技术的磷钨杂多酸化学修饰电极的组装及其电催化

将 Dawson型磷钨杂多酸盐 K6 P2 W1 8O6 2 · 1 0 H2 O( P2 W1 8)掺杂到溶胶 -凝胶中 ,滴涂在碳糊电极表面 ,制备成化学修饰电极 .并对该化学修饰电极的电化学行为 ,包括溶液 p H值的影响和电极稳定性等进行了详细的研究 .结果表明 ,此电极既保持了该杂多酸的电化学活性和电催化性能 ,又具有良好的稳定性和灵敏度 .实验发现 ,在 0 .5mol/L H2 SO4溶液中 ,掺杂在溶胶 -凝胶膜中的 P2 W1 8的第 3、第 4个还原峰对 NO- 2 离子具有很好的电催化活性 ,且催化电流同 NO- 2 浓度呈线性关系 .同时 ,P2 W1 8的第 3、第 4个还原峰对分子氧也具有很好的电催化活性 .

Fabrication of Chemically-modified Electrode Containing 2:18 Tungstophosphate Anions Based on Sol-gel Technique and Its Electrocatalysis

The anions of Dawson type tungstophosphate acid were modified on the surface of a carbon paste electrode by the sol gel technique. The electrochemical behavior of the modified electrode was studied in detail, including pH dependence, stability and so on. Experimental results show that the modified electrode not only maintains the electrochemical activity and electrocatalytic properties of P 2W 18 , but also has a good stability and sensibility. In 0 5 mol/L H 2SO 4 solution, the third and the fourth cathodic peaks of P 2W 18 doped in sol gel film have a good catalytic effect on the reduction of nitrite. The catalytic current is proportional to NO - 2 concentration. At the same time, we found that the third and the fourth cathodic peaks of P 2W 18 doped in sol gel film had an excellent effect on the reduction of dioxygen. WT5HZ]