Alumina‐Supported CoFe Alloy Catalysts Derived from Layered‐Double‐Hydroxide Nanosheets for Efficient Photothermal CO2 Hydrogenation to Hydrocarbons

Abstract A series of novel CoFe‐based catalysts are successfully fabricated by hydrogen reduction of CoFeAl layered‐double‐hydroxide (LDH) nanosheets at 300–700 °C. The chemical composition and morphology of the reaction products (denoted herein as CoFe‐ x ) are highly dependent on the reduction temperature ( x ). CO 2 hydrogenation experiments are conducted on the CoFe‐ x catalysts under UV–vis excitation. With increasing LDH‐nanosheet reduction temperature, the CoFe‐ x catalysts show a progressive selectivity shift from CO to CH 4 , and eventually to high‐value hydrocarbons (C 2+ ). CoFe‐650 shows remarkable selectivity toward hydrocarbons (60% CH 4 , 35% C 2+ ). X‐ray absorption fine structure, high‐resolution transmission electron microscopy, Mössbauer spectroscopy, and density functional theory calculations demonstrate that alumina‐supported CoFe‐alloy nanoparticles are responsible for the high selectivity of CoFe‐650 for C 2+ hydrocarbons, also allowing exploitation of photothermal effects. This study demonstrates a vibrant new catalyst platform for harnessing clean, abundant solar‐energy to produce valuable chemicals and fuels from CO 2 .