Efficient Electrochemical Nitrogen Fixation over Isolated Pt Sites

Abstract

Recently, ambient electrochemical N2 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 WO3 nanoplates exhibit the optimum electrochemical NH3 yield rate (342.4 µg h−1 mg−1Pt) and Faradaic efficiency (31.1%) in 0.1 m K2SO4 at −0.2 V versus RHE, which are about 11 and 15 times higher than their nanoparticle counterparts, respectively. The mechanistic analysis indicates that N2 conversion to NH3 follows an alternating hydrogenation pathway, and positively charged isolated Pt sites with special Pt−3O structure can favorably chemisorb and activate the N2. Furthermore, the hydrogen evolution reaction can be greatly suppressed on isolated Pt sites decorated WO3 nanoplates, which guarantees the efficient going‐on of nitrogen reduction reaction.

Comprehensive Understanding of the Thriving Ambient Electrochemical Nitrogen Reduction Reaction

“…showed that N 2 can be electrochemically reduced to NH 3 at isolated Pt sites on a WO 3 plate, while the HER activity of these sites can be inhibited. [ 73 ] Specifically, the electron‐rich Pt more easily adsorbs H atoms, and the number of surface‐adsorbed H atoms is positively correlated to HER activity. Isolated Pt atoms are often coordinated by atoms such as O and N that anchor Pt to make it more electron‐deficient and thus less prone to adsorb H atoms and be attacked by N 2 .…”

Exploration and Investigation of Periodic Elements for Electrocatalytic Nitrogen Reduction

“…Contrarily, single Pt atoms grown on WO 3 manifested 31.10% efficiency with 342.4 µg h −1 mg cat −1 . [207] We believe, further in-depth studies are required to study the nature of Pt toward NRR. Table 8 shows the summary of catalytic properties of d 8 -transition elements toward NRR.…”

“…Contrarily, single Pt atoms grown on WO 3 manifested 31.10% efficiency with 342.4 µg h −1 mg cat −1 . [ 207 ] We believe, further in‐depth studies are required to study the nature of Pt toward NRR.…”

Advancement of Bismuth‐Based Materials for Electrocatalytic and Photo(electro)catalytic Ammonia Synthesis

“…The in situ Fourier transform infrared (FTIR) can unravel the formation of intermediates on the catalyst surface during NRR. [60,81] For example, in EC-NRR, using N, P codoped porous carbon, the in situ FTIR spectra showed an absorption peak at 1106 cm −1 attributed to the NN stretching (Figure 2h). This peak intensity increased along with the prolonged reaction time, suggesting the cleavage of NN bond into a single bond.…”