Structure-activity Relationship of Cu Species in the Ethanol Upgrading to n-Butanol

Cu-based catalysts have been widely used in ethanol upgrading to value-added chemicals, however the selectivity towards target products is still not satisfactory due to the complexity of reaction network. Herein, we take the ethanol conversion to n-butanol as an example, and demonstrate that there are relationships of the ethanol conversion, the selectivity of n-butanol and ethyl acetate, and the rate of n-butanol formation with the ratios of the surface area of Cu(0)and Cu+. Both Cu(0)and Cu(+)are involved in the formation of ethyl acetate, and the ratio is indicative of the catalytic performance, being the higher the ratio, the higher activity of ethanol conversion to n-butanol but lower selectivity towards ethyl acetate. This work will help develop more efficient and selective catalysts for ethanol upgrading.