Highly dispersed face-centered cubic copper–cobalt alloys constructed by ultrafast carbothermal shock for efficient electrocatalytic nitrate-to-ammonia conversion

Abstract

Ammonia is a promising new generation of green energy that has the potential to replace hydrogen energy and facilitate the energy structure optimization of human society. However, the technology of green ammonia production under ambient conditions is still immature. It is urgent to develop new strategies for efficient and green ammonia production adapted to distributed energy, resource environment, and human health. Hereon, a highly dispersed face-centered cubic copper–cobalt alloy was prepared by ultrafast carbothermal shock for green ammonia production from nitrate under ambient conditions. The Cu2.5Co alloy achieves a remarkable ammonia yield of 164.23 μmol/h/cm2 and an exceptional faradaic efficiency of 96.29% at −0.25 V and −0.05 V versus reversible hydrogen electrode in a neutral solution. The electronic regulation of Co on Cu reduces the Tafel slope from 182 mV/dec of monometallic Cu to 108 mV/dec of bimetal Cu2.5Co alloy; the addition of Co optimizes the overall catalytic activity of the catalyst. This work provides a new idea for the design and synthesis of high-efficiency electrocatalyst for green ammonia production from nitrate and water under ambient conditions.