Effect of Heteroatom and Charge Reconstruction in Atomically Precise Metal Nanoclusters on Electrochemical Synthesis of Ammonia

Abstract

Although atomically precise metal nanoclusters (NCs) are widely used in catalysis, a wide gap exists between state‐of‐the‐art performance and practical requirements. Regulating the intrinsic activity of NCs is critical for the rational design and synthesis of highly efficient catalysts. Herein, M4Ni2 NCs (M = Au, Ag) with improved electrocatalytic nitrogen reduction reaction (NRR) activity due to the introduction of Ni are synthesized, which significantly suppresses the H2 generation competition reaction. Ag4Ni2 NCs exhibit the best NRR activity at −0.2 V versus RHE with a NH3 yield of 23.32 µg mg–1 h–1 and a faradic efficiency of 78.97% due to the higher N2 chemisorption ability and lower rate‐determining barrier. Meanwhile, ligand partial detachment of NCs during electrocatalysis offers exposed active sites and induces the charge reconstruction, also contributing to the outstanding NRR performance. Based on the precise composition and structure, deep insights into the NRR mechanism at the atom level are provided by in situ Fourier‐transformed infrared spectroscopy and ab initial calculation. The study presents an efficient strategy based on heteroatom doping and charges reconstruction to promote NCs catalytic performance.

Rigorous Assessment of Cl−‐Based Anolytes on Electrochemical Ammonia Synthesis

“…+ is also limited, due to a lack Comparison of ammonia yield rates reported in literature and the calibrated values based on this work. [32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49] of oxidized F − . (4) Long-term electrolysis experiments were carried out to evaluate the diffusion and oxidation of NH 4…”

“…Figure 5.Comparison of ammonia yield rates reported in literature and the calibrated values based on this work [32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49]. …”

A review on catalysts for electrocatalytic and photocatalytic reduction of N2to ammonia

“…Recently, Han et al 25 synthesized M 4 Ni 2 NC (M = Au, Ag) catalysts for the e-NRR by doping NCs with heteroatoms. The Ag 4 Ni 2 NCs showed the best faradaic efficiency of 78.97% and an NH 3 yield of 23.32 μg mg −1 h −1 at −0.2 V vs. RHE.…”

“…At present, the Haber-Bosch 3 process is widely used in the industry to synthesize ammonia, that is, nitrogen and hydrogen are combined to form ammonia under the action of a high-temperature and high-pressure catalyst (iron). The reaction conditions of this process are very harsh and require high pressure (15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25) and high temperature (673-873 K). 4 Due to the high temperature and pressure conditions, the process consumes a lot of energy, producing millions of tons of carbon dioxide by-products every year.…”

Structure and assembly of a hexanuclear AuNi bimetallic nanocluster

“…With the participation of P and S atoms in the Au 4 plane, the average distances of the adjacent gold atoms and the opposite gold atoms are respectively 3.4 and 4.8 Å, which are longer than those in octahedral M 6 systems. [30][31][32][33][34][35][36][37][38] The open and giant [-PPh 2 -Au-S-Au-] 2 ring would be a potential site for further applications such as catalysis and molecular recognition. (2) The rigid Ni-PCP pincer complex was introduced in nanoclusters for the first time (Fig.…”