WO3/In2S3 with NiOx for photocathodic protection of 304 stainless steel and for inhibiting sulfide photocorrosion

[Display omitted] •WO3/In2S3/NiOx composite photoanode was successfully prepared by facile method.•The solvent used in the preparation of In2S3 was water, which was green and environmentally friendly.•A change in the chemical state of Ni2+ in NiOx before and after the test of the WO3/In2S3/NiOx composite photoanode.•The composite photoanode kill three birds with one stone. A WO3/In2S3/NiOx composite photoanode was prepared by hydrothermal, chemical bath deposition, and impregnation methods. The photocurrent density of the WO3/In2S3/NiOx composite photoanode was 0.85 mA/cm2, about four times that of pure In2S3. Coupling the composite photoanode with 304 stainless steel negatively shifted the open-circuit potential to −665 mV under white light condition. The enhanced performance is due to the formation of a heterostructure and the co-catalyst load, which promote carrier separation and inhibit photocorrosion. This composite photoanode is a good candidate for photocathodic protection.