Synthesis and photocatalytic activity of CuYyFe2−yO4–CuCo2O4 nanocomposites for H2 evolution under visible light irradiation

Spinel-type CuYyFe2−yO4–CuCo2O4 nanocomposites have been successfully synthesized via a facile citric acid (CA)-assisted sol–gel method. And the as-synthesized nanocomposites have been characterized by techniques of X-ray diffraction (XRD), nitrogen adsorption BET method, and transmission electron microscopy (TEM). The samples are composed of primary ultrafine nanoparticles with nearly spherical morphology and mean particle size of about 80 nm. Moreover, the photocatalytic H2 evolution activity of the as-obtained samples has been evaluated from aqueous oxalic acid solution under visible light irradiation. The influence of photocatalyst type, calcination temperature, Y3+ doping content, and the durability of the as-obtained photocatalyst have been investigated in detail. The best photocatalytic H2 evolution activity was obtained over the as-synthesized CuY0.08Fe1.92O4–CuCo2O4 nanocomposite.