Activating dual atomic electrocatalysts for the nitric oxide reduction reaction through the P/S element

The development of efficient atomic electrocatalysts to resolve the activity and selectivity issues of the nitric oxide reduction reaction (NORR) has increasingly received more attention but is still challenging. The current research on the dual atomic NORR electrocatalyst is exclusively focused on TM atoms. Herein, we propose a novel mechanism of introducing a P/S element, which takes advantage of finite orbitals to active the transition metal (TM) atoms of dual atomic electrocatalysts for NORR. The finite orbitals can hinder the capture of the lone pair electrons of NO but modulate the electronic configurations of the neighboring TM and thus the "donation-backdonation" mechanism can be realized. Through large-scale first-principles calculations, the catalytic performance of a series of P/S-TM biatoms supported by the monolayer CN (P/S-TM@CN) is evaluated. According to a "four-step" screening strategy, P-Cu@CN and S-Ni@CN are successfully screened as promising catalysts with outstanding activity and high selectivity for direct NO-to-NH₃ conversion. Moreover, we identify Δε_d-p as a valid descriptor to evaluate the adsorption of NO on such catalysts, allowing for reducing the number of catalytic candidates. Our work thus provides a new direction for the rational design of dual atomic electrocatalysts.