Efficient carrier separation in Al-BiVO4/Co2AlO4 photocatalytic fuel cell photoanode through Schottky junction along with Co2+/Co3+ cycle

Photocatalytic fuel cell technology is one of the effective ways to solve the energy crisis and water pollution. The development of efficient photoanodes is the key to the practical application of photocatalytic fuel cell. Herein, BiVO 4 was doped with Aluminum, and then combined with Co 2 AlO 4 to construct a Schottky junction photoanode of Al-BiVO 4 /Co 2 AlO 4 . The photocatalytic fuel cell system achieved an open-circuit voltage of 0.38 V, a short-circuit current density of 1.01 mA cm −2 , and a maximum power density of 0.13 mW cm −2 using Al-BiVO 4 /Co 2 AlO 4 photoanode in the PHNa electrolyte with 5 mg L −1 ibuprofen as fuel. The current generated by Al-BiVO 4 /Co 2 AlO 4 fueled with ibuprofen was higher than that produced by fuels such as tartaric acid, malic acid, methyl orange and basic fuchsin. The photoelectric conversion performance of Al-BiVO 4 /Co 2 AlO 4 was dramatically improved compared to BiVO 4 , which was basically attributed to Schottky barrier between Al-BiVO 4 and Co 2 AlO 4 along with Co 2+ /Co 3+ cycle, promoting the efficient separation and injection of Al-BiVO 4 /Co 2 AlO 4 carriers.