Fe2O3/NiO photocathode for photocatalytic methanol fuel cell: An insight on solar energy conversion

A promising photocathode material based on Fe2O3/NiO heterostructure was developed for efficient photoelectric conversion in a methanol fuel cell. The Fe2O3/NiO heterogeneous film was prepared via in-situ hydrothermal synthesis and then cathodic electrodeposition process. Surface photovoltage results showed that after electrodeposition of NiO on the Fe2O3 film, the separation direction of photogenerated electrons and holes was reversed. The photogenerated electrons accumulated on the surface of Fe2O3/NiO photocathode can induce the oxygen reduce reaction due to the relatively high conduction band level of the entire semiconductor composite. In addition, the Fe2O3/NiO based photocatalytic methanol fuel cell showed significant improvements under illumination of simulated sunlight, and the short-circuit current and open-circuit voltage reach 183 μA/cm2 and 0.48 V respectively. The work provided a new vision for solar - chemical energy conversion in the fuel cell.