Emerging Role of p‐Block Element in Catalyzing Electrochemical NOx Reduction to Ammonia: A Theoretical Perspective

Abstract

AbstractFixing earth‐abundant nitrogen elements into essential compounds is one of the ultimate issues for mankind. Electrochemical nitrogen fixation is regarded as promising to replace the Haber‐Bosch (HB) process at current stage. However, direct fixation of N2 is found skeptical recently due to the stable chemical properties of N2 molecule. In this regard, the more reactive nitrogen oxides (NOx) species came to light as an alternative of nitrogen sources. Since NOx species is one of the most prevalent pollutants in wastewater, it is also desired that NOx reduction can transform these detrimental ingredients into value‐added products such as ammonia. Like other chemical reactions, the performance of electrochemical NOx reduction to ammonia (eNOxRA) has a strong relation with the performance of catalysts. Previously, catalyst design of eNOxRA is dominantly based on transition metals. The role of p‐block elements in eNOxRA is not fully realized until very recent years. In this perspective, the up‐to‐date advances of p‐block‐contained catalysts in eNOxRA are concluded, with the role of p‐block elements specifically classified and discussed. Several strategies are also introduced to delicately investigate the interaction between p‐block elements and NOx species. At the end, some dilemmas and potential opportunities are proposed to achieve a more comprehensive understanding toward developing high‐efficient p‐block electrocatalyst for NOxRA.