Distinctive p-d Orbital Hybridization in CuSb Porous Nanonetworks for Enhanced Nitrite Electroreduction to Ammonia

Abstract

Electrochemical nitrite reduction reaction ( ${\mathrm{NO}}_2^{-}\mathrm{RR}$ ), as a green and sustainable ammonia synthesis technology, has broad application prospects and environmental friendliness. Herein, an unconventional p-d orbital hybridization strategy is reported to realize the fabrication of defect-rich CuSb porous nanonetwork (CuSb PNs) electrocatalyst for ${\mathrm{NO}}_2^{-}\mathrm{RR}$ . The crystalline/amorphous heterophase structure is cleverly introduced into the porous nanonetworks, and this defect-rich structure exposes more atoms and activated boundaries. CuSb PNs exhibit a large NH₃ yield ( $r_{N{H}_3}$ ) of 946.1 µg h^-1 $m_{\mathrm{cat}}^{-1}$ and a high faradaic efficiency (FE) of 90.7%. Experimental and theoretical studies indicate that the excellent performance of CuSb PNs results from the defect-rich porous nanonetworks structure and the p-d hybridization of Cu and Sb elements. This work describes a powerful pathway for the fabrication of p-d orbital hybrid defect-rich porous nanonetworks catalysts, and provides hope for solving the problem of nitrogen oxide pollution in the field of environment and energy.

Keywords: CuSb bimetallic material; electrocatalysis; nitrite reduction reaction; p-d orbital hybridization; porous nanonetwork.