Cellulose-assisted one-step liquid-phase synthesis of cuprous oxide nanoframes for efficient degradation of 4-nitrophenol: Oxygen vacancy engineering and crystal plane effect

Abstract

In this study, we report a cuprous oxide nano-framework catalyst with abundant oxygen vacancies and multiple exposed crystalline surfaces. The catalyst exhibits excellent catalytic performance in the hydro-reduction reaction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) with good reusability. Experimental and theoretical simulations showed that the construction of oxygen vacancies induced a change in the corresponding atomic configuration and electronic properties of the catalyst, which contributed to the improvement of the adsorption of 4-NP and the capture and activation of H atoms, thus accelerating the transfer process of reactive hydrogen and electrons to 4-NP using the catalyst as a mediator. In addition, the rough surface of the nano-framework exposed a variety of crystalline facets, among which the (210) facets possessed more suitable H atom adsorption energy and more electron transfer compared to the (100) facet, which further improved the hydrogenation performance of the catalyst. This study provides a catalyst design strategy based on the synergy of oxygen vacancies and crystalline surfaces for the efficient degradation of organic pollutants.