FeNi3 nanoparticles for electrocatalytic synthesis of urea from carbon dioxide and nitrate

Due to the environmental pollution and high energy consumption associated with the conventional industrial Bosch-Meiser method, electrocatalytic urea synthesis emerges as a promising and sustainable alternative route. In this work, we constructed and utilized nitrogen-doped porous carbon loaded with bimetallic FeNi3 alloy nanoparticles as an efficient electrocatalyst for synthesizing urea from carbon dioxide (CO2) and nitrate (NO3-). The created FeNi3 alloy within FeNi/NC served as the active site for the C-N coupling reaction, generating a higher urea yield of 496.5 & mu;g h(-1) mg(cat.)(-1) with a correlating faradaic efficiency (FE) of 16.58% at -0.9 V versus the reversible hydrogen electrode (vs. RHE), when in comparison to monometallic Fe/NC and Ni/NC catalysts. Moreover, we also monitored the urea generation process via in situ Raman spectroscopy technology, which enabled the identification of two critical reaction species, namely O-C-O and N-C-N, inferring that C-N coupling acted as the key reaction step.