Engineering of mixed metal oxides photocatalysts derived from transition-metal-based layered double hydroxide towards selective oxidation of cyclohexane under visible light

In this work, visible-light-driven mixed metal oxide nanostructures were synthesized selecting layered double hydroxide (LDHs) as precursors. Such LDHs-derived mixed metal oxide photocatalysts possessed distinct difference in cyclohexane oxidation under visible light, which was mainly due to the controllable composition of metal cations. Through the analysis of photocatalytic performances, it was figured out that, Cr0.2Mg3AlO showed the best catalytic activity among the series of photocatalysts, possessing 12.5% conversion and 96.7% recyclability for oxidation of cyclohexane. The superior oxidation performance of Cr0.2Mg3AlO was largely dependent on the formation of MgAlO/MgCr2O4 heterojunction, and it matched band structure could effectively enhance the absorption of visible light and the separation of electron-holes, and therefore accelerated the photocatalytic activity. This work provided an effective strategy for the preparation of highly efficient photocatalysts toward oxidation of cyclohexane.