Poly(3-phenylthiophene)-based Hybrid Conducting Polymers as Catalyst Support in PEMFC

摘要

In this paper, we report on the capability of poly(3-feniltiofeno), and its copolymers con 3,4(ethylenedioxithiophene) and thiophene hybrid electronic/ionic conductors to be used as Pt support in PEMFC, replacing both the conductive carbon support and the ionomer hinder. The results obtained indicate that all synthesized polymer have low electronic conductivity, the value being independent of the polymer and the doping agent employed, with ionic conductivities in the range of 10(-5)-10(-3) S.cm(-1). The cell containing the P(3PhT-co-EDOT) copolymer as Pt support has a superior performance, in terms of the values of maximum potential (0.9V), current density (250 mA.cm(-2)) and power density. A decrease on current and power densities cell performance was detected on increasing temperature or gas (hydrogen and oxygen) pressure. This behaviour, opposite to that commonly observed in PEMFC, where increasing the working temperature or gas pressure usually enhance the cell performance, was explained in terms of a loss of catalytic activity due to the conducting polymer degradation in the cell strong acid media.