Boosting H Production from a BiVO Photoelectrochemical Biomass Fuel Cell by the Construction of a Bridge for Charge and Energy Transfer.

Utilizing a photoelectrochemical (PEC) fuel cell to replace difficult water oxidation with facile oxidation of organic wastes is regarded as an effective method to improve the H production efficiency. However, in most reported PEC fuel cells, their PEC activities are still low and the energy in organic fuels cannot be effectively utilized. Here, a unique BiVO PEC fuel cell is successfully developed by utilizing the low-cost biomass, tartaric acid, as an organic fuel. Thanks to the strong complexation between BiVO and tartaric acid, a bridge for the charge and energy transfer is successfully constructed, which not only improves the photoelectric conversion efficiency of BiVO , but also effectively converts the chemical energy of biomass into H . Remarkably, under AM1.5G illumination, the optimal nanoporous BiVO photoanode exhibits a high current density of 13.54 mA cm at 1.23 V vs reversible hydrogen electrode (RHE) for H production, which is higher than that of previously reported PEC water splitting systems or PEC fuel cell systems. This work opens a new path for solving the low PEC H production efficiency and provides a new idea for improving the performances and energy conversion efficiency in traditional PEC fuel cells.