Ambient electrosynthesis of urea with nitrate and carbon dioxide over a CuRu alloy catalyst

Abstract

Urea synthesis under mild conditions starting from the electrocatalytic coupling of carbon dioxide (CO₂) and nitrate represents a promising alternative experimentally to conquer the huge energy consumption in the industrial Haber–Bosch process. Herein, an electrocatalyst consisting of CuRu alloy nanoparticles on carbonized cellulose (CuRu-CBC) is designed and realizes the urea yield rate of 394.85 ± 16.19 μg h⁻¹ mg_cat⁻¹ and an ultrahigh faradaic efficiency (FE) of 68.94 ± 3.05% at −0.55 V (vs. RHE) under ambient conditions. Further XAS analyses indicated that the favored internal electron transfer between Cu and Ru dual active sites significantly improved the C–N coupling activity. Various characterizations, including in situ ATR-SEIRAS and DEMS analysis highlighted the favorable generation of key intermediates *CO and *NH, making CuRu-CBC a promising catalyst for urea synthesis.