Conductive Polymer-Titania Photocathode Development for Hydrogen Production

Abstract

Polybithiophene and polybithiophene-titania films were electropolymerized under galvanostatic conditions on carbon fibre paper substrates and tested under AM1.5G conditions in 0.5 mM H2SO4 in order to evaluate their catalytic performance, their photonic conversion efficiency, as well as their Faradaic photoelectrochemical performance for hydrogen generation. The electrochemical data indicates that the films were stable and showed promise as a viable photocathode material as they significantly reduced the cathodic overpotential needed to promote hydrogen generation up to a current density of 75 µAcm-2. The photonic efficiency was low and showed a maximum incoming photonic conversion efficiency (IPCE) at a current density of 240 µAcm-2. Substrate considerations such as sub-micron architectural variables should be further investigated alongside film thickness and nanoparticle composition to optimize the photonic and catalytic performance.