One-stone, two birds: Alloying effect and surface defects induced by Pt on Cu2−xSe nanowires to boost C-C bond cleavage for electrocatalytic ethanol oxidation

The high-efficient C-C bond cleavage is the key for ethanol electrooxidation. In this work, PtCu/Cu2−xSe nanowires (NWs) with abundant surface defects were constructed and exhibited remarkable activity of 5.03 A mg−1Pt as well as 5.29 A mg−1Pt for ethanol oxidation and methanol oxidation, respectively, which are 5.0 and 5.3 fold of commercial Pt/C. ex situ, in situ experiments and calculation results reveal that the formation of PtCu alloys lowered the d-band level to promote the adsorption of hydroxyl species. The abundant defects created high density of low-coordinated atoms to boost the reaction kinetics. Thus, PtCu/Cu2−xSe NWs displayed enhanced C-C bond cleavage ability and high selectivity for C1 products (CO2). The assembled direct ethanol fuel cells (DEFCs) with PtCu/Cu2−xSe NWs as anode provided an open-circuit voltage (OCV) of 0.773 V and a peak power density of 7.8 mW cm−2. This work not only give us a potential catalyst for C-C bond cleavage, but also provides an effective strategy to enhance the electrocatalytic activity of ethanol/methanol oxidation.