Construction of frustrated lewis pairs in ZnO surface for boosting electrocatalytic NO reduction to NH3: Theoretical prediction and experimental validation

Abstract

Herein, we reported the design of unique FLPs for electrocatalytic reduction of nitric oxide (NOER) through anion doping on the ZnO (100) surface. The results demonstrated that the introduced dopant and its adjacent non−bonding Zn site function as a Lewis base and Lewis acid, respectively, to synergistically activate NO molecules. Using density functional theory for material screening, P−doped ZnO is predicted to exhibit rather high NOER activity with an ultralow limiting potential (−0.04 V), accompanied by the excellent suppression effect on the competitive side reactions to guarantee its high selectivity for NH3 production. Motivated by the theoretical prediction, the synthesized P−doped ZnO catalyst showed a high NH3 yield rate (218.2 μmol h−1cm−2 at −0.7 V) and a high Faradaic efficiency (91.4 %), as confirmed by our experimental measurements. This work not only suggests a high−performance catalyst for NO reduction but also expands upon the potential applications of FLPs in electrocatalysis.