祝贺任勇齐等同学的文章被 Chinese Chemical Letters 接受发表！

祝贺任勇齐等同学的文章

“Layer-by-layer enriching active Ni-N₃C sites in nickel-nitrogen-carbon electrocatalysts for enhanced CO₂-to-CO reduction”

被Chinese Chemical Letters接受发表！

Abstract

Transition metal and nitrogen co-doped carbons (M-N-C) have proven to be promising catalysts for CO₂ electroreduction into CO because of the high activity and selectivity. Effective enrichment of the active transition metal coordinated nitrogen sites is desirable but is challenging for a practical volumetric productivity. Herein, we report four kinds of model electrocatalysts to unveil this issue, which include the NC structures with surface N-functionalities, Ni-N-C_I with one layer of surface Ni-N₃C sites, NC@Ni-N-C_I with surface N-functionalities and underneath Ni-N3C sites as well as Ni-N-C_II with doubled surface Ni-N₃C sites. The X-ray absorption spectroscopy indicates the coordination configuration of Ni-N3C. For NC catalysts, when N-doping level increased from 3.5 at% to 8.4 at%, the CO partial current density increased from below 0.1 mA/cm² to 3 mA/cm². Introducing one layer of Ni-N₃C onto the NC structures leads to a 54 times higher CO partial current density than that of NC, in the meantime the FECO is 66 times higher. Furthermore, doubling the density of surface Ni-N₃C sites by a layer-by-layer method doubles the CO partial current density (jCO), indicating its potential to achieve a high density of active coordinated sites and current densities.