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

Decarbonizing N-2 conversion is particularly challenging, but essential for sustainable development of industry and agriculture. Herein, we achieve electrocatalytic activation/reduction of N-2 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 N-2 adsorbed on the Fe site. More importantly, we reveal that the reactivity of X/Fe-N-C catalysts for N-2 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 N-2 hydrogenation. With the most active H*, the Pd/Fe dual-atom site promotes the turnover frequency of N-2 reduction by up to 10 times compared with the pristine Fe site.