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 dif-ference 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% recycla-bility 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.

Automated summary

Visible-light-driven mixed metal oxide nanostructures were synthesized using layered double hydroxide (LDHs) as precursors. The LDHs-derived mixed metal oxide photocatalysts showed distinct differences in cyclohexane oxidation under visible light, mainly due to the controllable composition of metal cations. Among the series of photocatalysts, Cr0.2Mg3AlO exhibited the best catalytic activity, with 12.5% conversion and 96.7% recyclability for cyclohexane oxidation. The superior oxidation performance of Cr0.2Mg3AlO was attributed to the formation of MgAlO/MgCr2O4 heterojunction, which enhanced the absorption of visible light and the separation of electron-holes, leading to accelerated photocatalytic activity. This work provided an effective strategy for the synthesis of highly efficient photocatalysts for cyclohexane oxidation.