NiFe layered double hydroxide/BiVO₄ photoanode based dual-photoelectrode photocatalytic fuel cell for enhancing degradation of azo dye and electricity generation

Photocatalytic fuel cell (PFC) has recently emerged as a promising technology for simultaneous solar photocatalytic degradation of organic compounds and recovery of chemical energy stored in the organic compounds. Enhanced PFC using NiFe layered double hydroxide (LDH)/BiVO₄ photoanode and Cu₂O/Cu photocathode is first reported in this paper. The experimental results obtained show that the heterojunction photoanode can extend the spectrum of visible light absorption and effectively increase the photocurrent density. The superior characteristics are attributed to the heterojunction which decreases the interface recombination at the NiFe-LDH/BiVO₄ junction and allows favorable Helmholtz layer potential drop_. The short-circuit current, open-circuit voltage and maximum power density of the NiFe-LDH/BiVO₄-Cu₂O/Cu PFC are 0.196 mA cm^-2, 0.647 V and 74 µW cm^-2, respectively, in photocatalytic degradation of methylene blue dye.