Electrocatalytically Activating and Reducing N2 Molecule by Tuning Activity of Local Hydrogen Radical.

Abstract

Decarbonizing N2 conversion is particularly challenging, but essential for sustainable development of industry and agriculture. Herein, we achieve electrocatalytic activation/reduction of N2 on X/Fe-N-C (X=Pd, Ir and Pt) dual-atom catalysts under ambient condition. We provide solid experimental evidence that local hydrogen radical (H*) generated on the X site of the X/Fe-N-C catalysts can participate in the activation/reduction of N2 adsorbed on the Fe site. More importantly, we reveal that the reactivity of X/Fe-N-C catalysts for N2 activation/reduction can be well adjusted by the activity of H* generated on the X site, i.e., the interaction between the X-H bond. Specifically, X/Fe-N-C catalyst with the weakest X-H bonding exhibits the highest H* activity, which is beneficial to the subsequent cleavage of X-H bond for N2 hydrogenation. With the most active H*, the Pd/Fe dual-atom site promotes the turnover frequency of N2 reduction by up to 10 times compared with the pristine Fe site.