CuIr Nanoparticles for Electrochemical Reduction of CO2 to t-BuOH

Abstract

Recent advances in electrocatalysts for the CO2 reduction reaction (CO2RR) have led to several promising results, including the large-scale production of low-carbon fuels. One of the next steps in this route is the generation of economically and scientifically valuable multicarbon (e.g., C-4) chemicals. However, this process has rarely been reported to-date and has generally suffered from a low production rate (j(partial) = 0.097 mA cm(-2)) and Faradaic efficiency (FE) of = 1%. This is largely due to the lack of efficient electrocatalysts for the complicated and interconnected reaction pathway of C-4 generation. Herein, CuxIr1-x alloy nanoparticles (NPs) are shown to convert CO2 into (CH3)(3)COH (t-BuOH) with a jpartial of 0.207 mA cm(-2) at a FE of 14.8%, which is the best performance toward C-4 production demonstrated so far. Furthermore, this study proposes a probable mechanism of C-4 formation based on density functional theory (DFT) calculations. The findings suggest that the C-4 production is facilitated by the strong electronic interaction between Cu and Ir and the high oxophilicity of the Ir-rich surface, which enhances the binding strength of oxygen-bound intermediates. This work opens the potential of Ir-based alloys for the CO2RR and highlights the production of C-4 chemicals beyond the currently available C-1-C-3 products.