N‐doped Ti3C2Tx MXene‐regulated metal‐oxide facilitates the efficient electrocatalytic CO2 reduction to CO

Abstract

CO2 electroreduction reaction (CO2ER) provides a promising pathway for scaling up the conversion of CO2 to CO using renewable electricity, thereby providing an alternative potential pathway to carbon neutrality. Typically, the reaction conducted in aqueous media is an ideal way on the standpoint of sustainability. However, the undesired hydrogen evolution reaction (HER) is feasible to occur on the catalyst surface together with CO2ER, thereby reducing the overall CO2‐to‐CO efficiency. In this work, we utilized the stacked structure of N‐doped Ti3C2Tx MXene material supported metal oxide (ZnO) to form a ZnO/N‐Ti3C2Tx catalyst in electrolytic CO2 reduction to CO. The catalyst exhibited an Faradaic efficiency (FCO) of 96.4% in the CO2ER at ‐0.967 V (vs. RHE) with a current density of 7.2 mA·cm‐2. ZnO acted as the active site for the CO2ER in ZnO/N‐Ti3C2Tx, while N‐doped Ti3C2Tx MXene was responsible for enhancing textural properties and electrical conductivity, which could promote the mass transfer of gas molecules and electron transfer to ZnO active sites, and further improving the activity. This work inspires the rational design of unique metal oxide/N‐Ti3C2Tx interfaces to regulate the high‐performance electrocatalytic selectivity of CO2 reduction.