Axial Chlorine-Induced Symmetry-Breaking Iron Single-Atom Catalyst for Electrochemical Ammonia Synthesis

被引：0

作者：

Wan, Jieying ^{[1
]}

Yang, Ji ^{[2
]}

Yang, Na ^{[3
]}

Sun, Yifei ^{[4
]}

Hu, Chuansheng ^{[5
]}

Zhao, Yang ^{[6
]}

Xu, Xiaoyan ^{[6
]}

Qi, Haifeng ^{[7
]}

Li, Xiaodong ^{[1
]}

Zhang, Hao ^{[1
]}

机构：

[1] Zhejiang Univ, State Key Lab Clean Energy Utilizat, Hangzhou 310027, Peoples R China

[2] Xiamen Univ, Coll Chem & Chem Engn, Xiamen 361005, Peoples R China

[3] Univ Elect Sci & Technol China, Sch Mat & Energy, Chengdu 611731, Sichuan, Peoples R China

[4] Xiamen Univ, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China

[5] Univ Sci & Technol China, Natl Synchrotron Radiat Lab, Hefei 230026, Anhui, Peoples R China

[6] Chinese Acad Sci, Dalian Inst Chem Phys, Dalian Natl Lab Clean Energy DNL, Dalian 116023, Peoples R China

[7] Cardiff Univ, Max Planck Cardiff Ctr Fundamentals Heterogeneous, Translat Res Hub, Cardiff CF24 4HQ, Wales

来源：

ACS CATALYSIS | 2025年 / 15卷 / 06期

基金：

欧盟地平线“2020”; 中国国家自然科学基金;

关键词：

electrochemical ammonia synthesis; nitrate reduction; Fe-N-C; single-atom catalyst; symmetry breaking; NITRATE REDUCTION;

D O I：

10.1021/acscatal.4c06501

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Electrochemical nitrate reduction reaction (NO3-RR) presents a sustainable method for ammonia synthesis. Single-atom catalysts possessing the symmetric planar four-ligand structure (M-N-4) serve as advantageous catalytic active sites for NO3-RR. However, the inherent extreme symmetry of the standard M-N-4 structure limits the reaction kinetics. Herein, we introduce a symmetry-breaking iron single-atom catalyst coordinated with axial chlorine on nitrogen-doped carbon (Cl-Fe-NC) for NO3-RR. Cl-Fe-NC exhibits a 99.4% ammonia Faradaic efficiency (FE) at -0.28 V vs reversible hydrogen electrode (RHE) with a 9396.7 mu g(NH3) h(-1) cm(-2) yield rate at -0.68 V vs RHE, remarkably surpassing that of Fe-NC (<80%, 4330.9 mu g(NH3) h(-1) cm(-2) at the same potential). Operando synchrotron radiation Fourier transform infrared (SR-FTIR) spectroscopy confirms that key intermediates, such as *NO, *NO-H-x, and sigma(N-H), are formed. Density functional theory (DFT) calculations attribute the optimized free energy of NO3-RR intermediates to the axial chlorine design, reducing the potential determination step barrier energy by up to 0.66 eV. The presence of axial Cl atoms modulates the symmetry of the single Fe atom, enhancing the adsorption of nitrate ions and the enrichment of critical intermediates during NO3-RR while inhibiting the hydrogen evolution reaction (HER). This discovery opens avenues for boosting electrochemical ammonia synthesis through the precise modulation of atomic structures by doping heteroatoms for symmetry breaking.

引用

页码：4507 / 4518

页数：12