Electrochemical Partial Reforming of Ethanol into Ethyl Acetate Using Ultrathin Co ₃O ₄ Nanosheets as a Highly Selective Anode Catalyst

Abstract

Electrochemical partial reforming of organics provides an alternative strategy to produce valuable organic compounds while generating H ₂ under mild conditions. In this work, highly selective electrochemical reforming of ethanol into ethyl acetate is successfully achieved by using ultrathin Co ₃O ₄ nanosheets with exposed (111) facets as an anode catalyst. Those nanosheets were synthesized by a one-pot, templateless hydrothermal method with the use of ammonia. NH ₃ was demonstrated critical to the overall formation of ultrathin Co ₃O ₄ nanosheets. With abundant active sites on Co ₃O ₄ (111), the as-synthesized ultrathin Co ₃O ₄ nanosheets exhibited enhanced electrocatalytic activities toward water and ethanol oxidations in alkaline media. More importantly, over the Co ₃O ₄ nanosheets, the electrooxidation from ethanol to ethyl acetate was so selective that no other oxidation products were yielded. With such a high selectivity, an electrolyzer cell using Co ₃O ₄ nanosheets as the anode electrocatalyst and Ni–Mo nanopowders as the cathode electrocatalyst has been successfully built for ethanol reforming. The electrolyzer cell was readily driven by a 1.5 V battery to achieve the effective production of both H ₂ and ethyl acetate. After the bulk electrolysis, about 95% of ethanol was electrochemically reformed into ethyl acetate. This work opens up new opportunities in designing a material system for building unique devices to generate both hydrogen and high-value organics at room temperature by utilizing electric energy from renewable sources.

Abstract

The preparation of electrocatalysts composed of earth-abundant elements enables the development of an electrochemical partial reforming process to simultaneously produce valuable organics and hydrogen under mild conditions.