Photo/Thermal Dual‐Activation Improves the Photocurrent of Bismuth Vanadate for PEC Water Splitting

Abstract

AbstractMaking full use of the whole sunlight spectrum and developing photoanode with high performance are the two crucial challenges to realizing the industrial application of PEC water splitting. Thermal‐activation is an ideal way to realize the full use of the whole sunlight spectrum as the thermal energy is easily generated by the long wavelength sunlight. Photo‐activation is an effect way to enhance the PEC performance of BiVO4 through the synergistic effects of its bulk charge transfer and surface properties. In this work, the combining of thermal‐activation and photo‐activation (dual‐activation) was conducted on the BiVO4 photoanode to improve its photocurrent performance. The results indicate that the dual‐activation dramatically improved the photocurrent density of BiVO4 photoanode from 0.62 mA cm−2 to 1.32 mA cm−2 at 1.23 VRHE, and the improvement could be ascribed to the synergistic effects of Ddonor enhancement and diminished Fermi level pinning effect. Besides, the charge transfer process in the BiVO4 photoanode was also effectively facilitated by the dual‐activation.