Cu–Co synergy enabling efficient tandem nitrate reduction to ammonia on engineered TiO2 nanofibers

Abstract

This study constructs a Cu₁–Co₁/TiO₂ catalyst featuring diatomic sites anchored on TiO₂ nanofibers. This architecture synergistically enables nitrate activation, reactive hydrogen species generation, and protonation of reaction intermediates. In neutral electrolyte environments, the catalyst effectively suppresses the hydrogen evolution reaction (HER), exhibiting exceptional selectivity for nitrate to ammonia conversion: at −0.9 V vs. RHE, it achieves a high NH₃ yield rate of 8.99 mg h⁻¹ cm⁻² with a faradaic efficiency (FE) of 93.22%.