Identification of M‐NH₂‐NH₂ Intermediate and Rate Determining Step for Nitrogen Reduction with Bioinspired Sulfur‐Bonded FeW Catalyst

Abstract

The multimetallic sulfur-framework catalytic site of biological nitrogenases allows the efficient conversion of dinitrogen (N 2 )toammonia (NH 3 )u nder ambient conditions. Inspired by biological nitrogenases,abimetallic sulfide material (FeWS x @FeWO 4 )was synthesized as ahighly efficient N 2 reduction (NRR) catalyst by sulfur substitution of the surface of FeWO 4 nanoparticles.T hus prepared FeW-S x @FeWO 4 catalysts exhibit ar elatively high NH 3 production rate of 30.2 ug h À1 mg À1 cat and aF araday efficiency of 16.4 %at À0.45 Vv ersus ar eversible hydrogen electrode in af low cell; these results have been confirmed via purified 15 N 2 -isotopic labeling experiments.I ns itu Raman spectra and hydrazine reduction kinetics analysis revealed that the reduction of undissociated hydrazine intermediates (M-NH 2 -NH 2 )o nt he surface of the bimetallic sulfide catalyst is the rate-determing step for the NRR process.T herefore,t his work can provide guidance for elucidating the structure-activity relationship of NRR catalysts.

Defect and interface engineering in metal sulfide catalysts for the electrocatalytic nitrogen reduction reaction: a review

“…5I). 81 Compared with FeWO 4 , the FeWS x @FeWO 4 exhibited stronger N 2 adsorption ability, suggesting that metal–sulfur bonds were beneficial for N 2 adsorption. Electrochemical measurements also indicated the better NRR performance of FeWS x @FeWO 4 , and an NH 3 yield of 30.2 μg h −1 mg cat −1 with a FE of 16.4% was achieved at −0.45 V in 0.1 M KOH (Fig.…”

Water-resistant organic–inorganic hybrid perovskite quantum dots activated by the electron-deficient d-orbital of platinum atoms for nitrogen fixation

“…41,58 Consequently, for selective NRR, the ideal catalysts of OIP QDs should be further designed with (1) a lower d-band state to weaken H adsorption and (2) abundant electron deficient sites with strong N 2 affinity. 54,59–61…”

Single-Metal-Atom Dopants Increase the Lewis Acidity of Metal Oxides and Promote Nitrogen Fixation

“…Doping another atom into the host surface is a feasible strategy to reach improved surface electronic properties and conductivity and further optimize the adsorption strength of the reaction intermediates, thereby being greatly favorable for enhancing the catalytic activity. Recently, cation and anion dopant-tuned catalysts, such as V/Zr-doped TiO 2 , , Fe-doped CeO 2 /W 18 O 49 , , S-doped FeWO 4 , and B-doped C 3 , have been developed for the improvement of NRR performance by generating the oxygen/nitrogen-vacancy sites (O v /N v ), also known as Lewis acid sites, with an empty orbital to trap the electron lone pair of the Lewis base N 2 molecules. However, the number of vacancy sites is extremely limited and easily vanishes during NRR as a result of N filling due to the high binding strength of N atoms on O v /N v , thus significantly hampering the NH 3 selectivity (<20%) and yield rate.…”

“…Recently, cation and anion dopant-tuned catalysts, such as V/Zr-doped TiO 2 , , Fe-doped CeO 2 /W 18 O 49 , , S-doped FeWO 4 , and B-doped C 3 , have been developed for the improvement of NRR performance by generating the oxygen/nitrogen-vacancy sites (O v /N v ), also known as Lewis acid sites, with an empty orbital to trap the electron lone pair of the Lewis base N 2 molecules. However, the number of vacancy sites is extremely limited and easily vanishes during NRR as a result of N filling due to the high binding strength of N atoms on O v /N v , thus significantly hampering the NH 3 selectivity (<20%) and yield rate. In addition, the presence of O v sites has been well established for facilitating water dissociation to H* in alkaline media and has also been explored for various catalytic applications. − Enlightened by the above discussion, systematic design strategies are urgently required to maximize the density of Lewis acid sites on the TMOs for enhancing N 2 interaction and stabilizing the key NRR intermediates along with suppressing the H* dimerization to achieve substantially high NH 3 FE and yield rate, but this remains a challenging issue.…”

“…CeO 2 /W 18 O 49 ,15,16 S-doped FeWO 4 ,17 and B-doped C 3 ,18 have been developed for the improvement of NRR performance by generating the oxygen/nitrogen-vacancy sites (O v /N v ), also known as Lewis acid sites, with an empty orbital to trap the electron lone pair of the Lewis base N 2 molecules. However, the number of vacancy sites is extremely limited and easily vanishes during NRR as a result of N filling due to the high binding strength of N atoms on O v /N v ,17 thus…”