Improving nitric oxide reduction reaction through surface doping on superstructures

Abstract

Electrochemical nitric oxide reduction reaction (NORR) combining the production of NH3 with the removal of atmospheric pollutant NO is regarded as a promising strategy for producing important chemicals and reducing environmental pollution. However, existing NORR electrocatalysts such as Cu(111) have disadvantages of low activity and selectivity. In this work, the Cu2Si/Cu(111) and Cu2Si/Si(111) superstructures are proposed as NORR electrocatalysts with high stability, activity and selectivity. The results indicate that doping p-block element Si on Cu(111) and transition metal Cu on Si(111) changes the surface chemical environment and local physical properties, optimizing NO adsorption energy and successfully getting rid of the energy barriers of 0.15 and 1.56 eV on Cu(111) and Si(111), respectively. It is of great interest to find that the interfacial effect suppresses the competitive hydrogen evolution reaction (HER) by improving the interlayer charge transfer and modulating Si-3pz orbital, thus ensuring the high NORR selectivity. This theoretical work paves a new way to help design better NORR electrocatalysts for producing renewable fuels from pollutant NO.