Abstract
Although Faraday efficiency (FE) for CO production of single-atom catalysts immobilized on nitrogen-doped carbon supports (M-N/C) for CO2 electrocatalytic reduction reaction (CO2RR) is generally over 90%, M-N/C catalysts demonstrate a poor reaction current density, much worse than the current density of industrial level. Herein, we first report a generalized strategy of amino-functionalized carbon supports to regulate electronic structure of M-N/C catalysts (M=Ni, Fe, Zn) to significantly increase current density of CO production. The aminated Ni single-atom catalyst achieves a remarkable CO partial current density of 447.6 mA cm-2 (a total current density over 500 mA cm-2) with a nearly 90% CO FE at a moderate overpotential of 0.89 V, and especially CO FE can be maintained over 85% in a wide operating potential range from -0.5 V to -1.0 V. DFT calculations and experimental researches demonstrate that the superior activity is attributed to enhanced adsorption energies of CO2* and COOH* intermediates caused by the change of electronic structure of aminated catalysts. This work provides an ingenious method for significantly increasing current density at industrial-relevant level of single-atom catalysts for CO2RR.
Fabricating high-loading Fe-N4 single-atom catalysts for oxygen reduction reaction by carbon-assisted pyrolysis of metal complexes