Novel Fe-MOF@Cu/NiAl-LDH as Photo-Catalysts in Methane Bireforming: Effect of Preparation Strategy

Abstract

In this work, Fe-MOF@Ni/CuAl-LDH nanocomposites are developed for the first time in photocatalytic CO2/CH4 conversion to ultrapure formaldehyde. The reaction takes place in a dynamic (continuous flow) photosystem working under atmospheric pressure in presence of visible-light irradiation. The visible-light-active photocatalysts are prepared using two strategies in order to enhance both morphology and optical properties of the new composite. First strategy based on growing of MOF on the in-situ N2 exfoliated LDH using solvothermal reaction (FMNHT and FMCHT), where, the MOF is formed on surface and/or inside lamellar layer. The second based on formation of LDH around the previously prepared Fe-MOF via microwave assisted method (NFMMW and CFMMW). The data herein indicate that, both samples NFMMW and CFMMW, have LDH/MOF strong electronic coupling and exhibit an adjustable band gap share in improve charge generation/separation rate, reduce e−/h+ recombination rate and increase light absorption capacity. Those characteristics provide higher efficiency in photocatalytic CH4/CO2 conversion and give high selectivity toward ultrapure formaldehyde formation (99.9%).