Interface-Enhanced Catalytic Selectivity on the C<sub>2</sub> Products of CO<sub>2</sub> Electroreduction
Zhen Li, Yao Yang, Zhenglei Yin, Xing Wei, Hanqing Peng, Kangjie Lyu, Fengyuan Wei, Li Xiao, Gongwei Wang, Héctor D. Abruña, Juntao Lu, Lin Zhuang
Abstract
Powered by renewable electricity, the electrochemical conversion of CO2 to liquid fuels and valuable chemicals is a meaningful approach to enable carbon cycling and tackle environmental issues. An intrinsic challenge has been the low efficiency and selectivity, in particular for deep reduction products. Here, we report on an interface-enhanced strategy for transforming the catalytic selectivity toward the CO2 reduction reaction (CO2RR). Inspired by the enzyme catalysis in nature, where the catalytic center is surrounded by a chemically selective environment, we create a thin layer of nitrogen-doped carbon (NxC) over the Cu surface. The NxC environment does not modify the electronic property of Cu but selectively enriches and activates CO2 molecules through the specific N–CO2 interaction, as experimentally identified. Such a Cu/NxC interface has boosted the faradic efficiency (FE) of the CO2RR to be above 90%, with the C2 products (ethylene and ethanol) being the majority (80% in total FE). The NxC overlayer also protects well the Cu substrate from the morphological change, thus increasing the catalytic stability. Our findings manifest that the chemical environment over the metal surface indeed plays a crucial, but not well recognized, role in selectivity control, which can hardly be achieved by solely tuning the electronic structure of metal catalysts.