Efficient Electrochemical Nitrogen Fixation over Isolated Pt Sites

Abstract Recently, ambient electrochemical N 2 fixation has gained great attention. However, the commercial Pt‐based electrocatalyst hardly shows its potential in this field. Herein, it is found that the isolated Pt sites anchored on WO 3 nanoplates exhibit the optimum electrochemical NH 3 yield rate (342.4 µg h −1 mg −1 Pt ) and Faradaic efficiency (31.1%) in 0.1 m K 2 SO 4 at −0.2 V versus RHE, which are about 11 and 15 times higher than their nanoparticle counterparts, respectively. The mechanistic analysis indicates that N 2 conversion to NH 3 follows an alternating hydrogenation pathway, and positively charged isolated Pt sites with special Pt−3O structure can favorably chemisorb and activate the N 2 . Furthermore, the hydrogen evolution reaction can be greatly suppressed on isolated Pt sites decorated WO 3 nanoplates, which guarantees the efficient going‐on of nitrogen reduction reaction.