The mechanism of ethanol steam reforming on Co10α-Al2O3 (0001) surface: A DFT study

摘要

? 2022ESR (Ethanol steam reforming) seems to be a promising way to produce hydrogen which has been proposed as the most desirable energy carriers to overcome the problem of fossil fuels shortage. The ESR mechanism on the optimized Co10|α-Al2O3 (0001) surface is investigated by means of DFT calculations. The results show that oxidation state of Co cluster and micro-chemical environment play important roles in the ESR reaction. C-C bond scission is favored on the Co0 site while C-O bond scission is likely to happen on the Cox+ site, and the energy barrier is influenced by the number of hydrogen and oxygen atoms that are bonded with C/O atom. ESR reaction is initiated by the O-H bond scission of ethanol on the Cox+ site: CH3CH2OH*→ CH3CH2O*→CH3*+CH2O*→CH2O*+OH*→H2COOH*→COOH*+H2*→CO*+H2*with the dehydrogenation of H2COO* as the rate-determining step.