C-Bound or O-Bound Surface: Which One Boosts Electrocatalytic Urea Synthesis?

Abstract

The electrocatalytic C-N coupling from carbon dioxide and nitrate under ambient conditions is kind of sustainable and promising alternative method for urea synthesis. To date, the influence of catalyst surface properties on molecular adsorption configuration and electrocatalytic urea synthesis activity is unclear. In this work, we proposed that the urea synthesis activity is closely linked with the localized surface charge on bimetallic electrocatalysts, it is found that a negatively charged surface induces C-bound path and boosts urea synthesis. The urea yield rate can reach 13.1 mmol g-1 h-1 on negatively charged Cu97 In3 -C, which is about 13 times that of positively charged Cu30 In70 -C counterpart with O-bound surface. This conclusion also applies to Cu-Bi and Cu-Sn systems. The molecular modification shifts the surface of Cu97 In3 -C to positively charged state, which leads to a sharp decline in urea synthesis performance. We demonstrated that the C-bound surface is more favorable than O-bound one to boost electrocatalytic urea synthesis.