Wide Potential CO<sub>2</sub>‐to‐CO Electroreduction Relies on Pyridinic‐N/Ni–N<sub><i>x</i></sub> Sites and Its Zn–CO<sub>2</sub> Battery Application
Zipeng Zeng, Aya Gomaa Abdelkader Mohamed, Xiang Zhang, Yaobing Wang
Abstract
Although metal–N‐doped carbons are promising electrocatalysts for CO 2 ‐to‐CO conversion due to their high conversion efficiency and current density, their commercial application is still challenging due to their narrow potential/current range. In general, a wide potential/current electrocatalyst is in high demand for industrial CO 2 electrocatalysis. Controllable strategy to tune N configurations toward pyridinic‐enriched metal–N x active sites is attractive. The synergetic effect of the ability of pyridinic N to capture Lewis acidic CO 2 and the characteristics of Ni–N active sites to inhibit the hydrogen evolution reaction (HER) can achieve a wide potential window, which has high practical value. Herein, the well‐chosen precursors resulting in a pyridinic‐enriched Ni–N x site can selectively catalyze CO 2 toward CO generation in aqueous media with a high Faradaic efficiency (FE) of 100% with an overpotential of 680 mV. Continuous CO FE > 90% was recorded under a wide range of potentials without decay. Motivated by its practical characteristics in CO 2 electrocatalysts, a Zn–CO 2 battery is assembled achieving a CO 2 –CO conversion efficiency of more than 90% in a wide discharge current window. Therefore, the results highlight that pyridinic‐enriched Ni–N x holds great promise as simultaneous CO‐selective electrocatalyst by suitably tuning M–N configurations as new perspective strategy.