Intermetallic PtSn Nanosheets with p-d Orbital Hybridization for Selective Hydroxylamine Electrosynthesis.

The electrocatalytic nitrate reduction to hydroxylamine (NHOH) is a challenging catalytic process that has gained significant attention. However, its performance is hindered by the low selectivity of the electrocatalysts. Here, intermetallic PtSn nanosheets with p-d orbital hybridization have been synthesized, which significantly enhances the performance of electrocatalytic nitrate reduction to NHOH. The Faradaic efficiency of NHOH reaches a maximum of 82.83 ± 1.55% at -0.10 V versus the reversible hydrogen electrode (vs RHE), and the yield of NHOH achieves 6.15 ± 0.32 mmol h mg at -0.25 V vs RHE. Mechanistic studies reveal that p-d orbital hybridization between p-block Sn and d-block Pt effectively enhances nitrate adsorption and NHOH desorption to boost electrochemical NHOH synthesis. Given their excellent performance in the electrochemical synthesis of NHOH, PtSn nanosheets are utilized as the cathode in an alkaline-acid hybrid Zn-NO battery to facilitate the production of NHOH, achieving an NHOH FE of 80.42%.