Insight into the dissociation mechanism of ethanol molecule over the nano-aluminum surface: a density functional theory study

Nano-Al-ethanol-based nanofluid fuel as a high-energy fuel has broad application prospects in the field of aviation vehicles. However, the detailed reaction mechanism of ethanol over the nano-Al surface is still a gray area. Hence, the adsorption and dissociation behaviors of ethanol molecule on the nano-Al (111) surface were investigated by a density functional theory calculation. Ethanol can be chemically adsorbed on the Al-top site by forming an Al–O bond. For ethanol dissociation, it can be dehydrogenated first to form ethoxy, acetaldehyde, and ethyl species, respectively. Then, ethoxy continues to dehydrogenate to generate acetaldehyde, ethylene oxide isomer, and formaldehyde. Finally, ethylene oxide can be dissociated to form formyl-methyl, formaldehyde, and ethylene species. Moreover, ethanol can also strip off both a hydrogen and a hydroxyl group concurrently to form ethylene. The generated acetaldehyde intermediate can be further decomposed into products such as acetyl, aldehyde group, and formyl-methyl species, which increase the variety of active substances of Al-ethanol based nanofluid fuel. This theoretical calculation provides a new insight for studying the decomposition mechanism of organic molecules in nanofluid fuels at the microscopic level.