Nitrate reduction to ammonium: from CuO defect engineering to waste NO_x-to-NH₃ economic feasibility

Critical to the feasibility of electrochemical reduction of waste NOx (NOxRR), as a sustainable pathway and to close the NOx cycle for the emerging NH3 economy, is the requirement of inexpensive, scalable and selective catalysts that can generate NH4+ with high yield, as indicated by our economic modelling.