聚苯胺修饰Pt/C催化剂对质子交换膜燃料电池动态响应的促进作用

将超级电容器材料聚苯胺引入电极催化剂中以缓冲燃料电池负载的变化.以硫酸为掺杂剂,将化学法合成的聚苯胺(PANI)与Pt/C超声分散混合,制成PANI-Pt/C催化剂.PANI-Pt/C的循环伏安测试和作为质子交换膜燃料电池阴极电催化剂的电池性能测试表明,PANI含量为10%时能够提高Pt/C催化剂对氧的还原动力学速度和燃料电池放电性能.电池在不同电流负载下的电压动态响应和对电池脉冲电流的动态响应以及PANI-Pt/C催化剂多电位电势阶跃计时电流测试显示,聚苯胺在催化剂中具有在瞬间电流负载时缓冲电池电压和电池大电流放电时平稳电压的作用.

Improvement of Dynamic Respondence of a Proton Exchange Membrane Fuel Cell over a Polyaniline-Modified Pt/C Catalyst

A proton exchange membrane fuel cell(PEMFC) possesses several advantages such as high energy density,low operating temperature,and fast startup,which make PEMFC the most promising and attractive candidate for electric vehicles and portable power.However,operations of fuel cells in the application of these systems are dynamic,and the transient behavior happens when the load changes.Transient operations may result in the oxidant starvation due to gas response rate lagging the loading rate,which will affect the durability and reliability of fuel cells further.In this paper,polyaniline(PANI) as a supercapacitor material was hybridized with a PEMFC catalyst in the electrode in order to buffer the load.PANI was synthesized by the chemical method using sulfide acid as the dopant.The PANI-Pt/C catalyst was prepared by mixing PANI and Pt/C in ultrasound and drying in air.The cyclic voltammetry of 10%PANI-Pt/C demonstrates that PANI can effectively improve oxygen reduction rate.The fuel cell performance is also improved by PANI according to the single fuel cell polarization experiment.The dynamic respondence of voltage to current and the multi-potential step chronoamperometry show that PANI can buffer and stabilize the voltage during the transient current loading and working at a large current.