Photocatalytic hydrogen production over CuGa2−xFexO4 spinel

Recovery of hydrogen from industrial H2S waste using spinel photocatalyst was studied. Spinel metal oxide photocatalysts (CuGa2−xFexO4 for x = 0.8, 0.6 and 0.4) were synthesized by ceramic route. They were loaded with 0.5 and 1 wt% noble metal oxide, RuO2. Their XRD pattern revealed a single phase cubic spinel crystalline structure for all the catalysts. SEM displayed small size cubic particles with the particle size decreasing with the decrease in iron content. 1 wt% RuO2 loaded CuGa1.6Fe0.4O4 decomposed H2S in aqueous 0.5 M KOH solution under visible light (λ ≥ 420 nm) irradiation and generated H2 to the tune of 10,045 μmol/h, giving rise to a high quantum efficiency of 21% at 510 nm.

► Spinel photocatalysts (CuGa2−xFexO4 for x = 0.8, 0.6 and 0.4) were synthesized. ► The prepared catalysts were characterized by XRD, SEM, EDS and UV-DRS. ► They were loaded with 0.5 and 1 wt% noble metal oxide, RuO2. ► Spinel photocatalysts decomposed H2S in aqueous 0.5 M KOH in visible light (λ ≥ 420 nm). ► 1 wt% Ru/CuGa1.6Fe0.4O4 generated 10,045 μmol/h of H2 and has quantum yield 21% at 510 nm.