Regulating Pd nanosheets by W-doping for electrochemical nitrate reduction to ammonia

Abstract

The electrochemical nitrate reduction reaction (NO₃RR) has been recently recognized as a prospective approach for green NH₃ production, while developing high-efficiency catalysts to attain both high activity and selectivity is crucial for an efficient NO₃RR process. Herein, we attempt to regulate Pd nanosheets via W doping (PdW) to enhance the NO₃RR activity, and the resulting PdW with a trace W amount (4.8 at%) exhibits an NH₃ yield of 2.3 mg h⁻¹ cm⁻² and a faradaic efficiency of 70.8% at −0.7 V (RHE) along with a favorable durability. Theoretical calculations reveal that surface W oxides on PdW can upshift the d-band center of Pd to result in enhanced NO₃⁻ activation and reduced reaction energy barriers for the critical step of *NH hydrogenation to *NH₂.