Efficient Photocatalytic Fuel Cell via Simultaneous Visible-Photoelectrocatalytic Degradation and Electricity Generation on a Porous Coral-like WO3/W Photoelectrode.

Abstract

Photocatalytic fuel cells (PFCs) have proven to be effective for generating electricity and degrading pollutants with a goal to resolve environmental and energy problems. However, the degradation of persistent organic pollutants (POPs), such as perfluorooctanoic acid (PFOA), remains challenging. In the present work, a porous coral-like WO3/W (PCW) photoelectrode with a well-designed energy band structure was used for the photoelectrocatalytic degradation of POPs and the simultaneous generation of electricity. The as-constructed bionic porous coral-like nanostructure greatly improved the light-harvesting capacity of the PCW photoelectrode. A maximum photocurrent density (0.31 mA/cm2) under visible light (λ > 420 nm) irradiation and a high incident photon conversion efficiency (IPCE) value (5.72% at 420 nm) were achieved. Because of the unique porous coral-like structure, the suitable energy band position, and the strong oxidation ability, this PCW photoelectrode-based PFC system exhibited a strong ability for simultaneous photoelectrocatalytic degradation of PFOA and electricity generation under visible-light irradiation, with a power output of 0.0013 mV/cm2 using PFOA as the fuel. This work provides a promising way to construct a reliable PFC using highly toxic POPs to generate electricity.