Symmetry-Breaking p-Block Antimony Single Atoms Trigger N-Bridged Titanium Sites for Electrocatalytic Nitrogen Reduction with High Efficiency

Hongfei Gu; Jiani Li; Xiangfu Niu; Jie Lin; Li-Wei Chen; Zedong Zhang; Ziqian Shi; Zhiyi Sun; Qingqing Liu; Peng Zhang; Wensheng Yan; Yu Wang; Liang Zhang; Pengfei Li; Xinyuan Li; Dingsheng Wang; Penggang Yin; Wenxing Chen

doi:10.1021/acsnano.3c07857

Symmetry-Breaking p-Block Antimony Single Atoms Trigger N-Bridged Titanium Sites for Electrocatalytic Nitrogen Reduction with High Efficiency

ACS Nano. 2023 Nov 14;17(21):21838-21849. doi: 10.1021/acsnano.3c07857. Epub 2023 Nov 1.

Authors

Hongfei Gu¹, Jiani Li², Xiangfu Niu³, Jie Lin⁴, Li-Wei Chen², Zedong Zhang⁵, Ziqian Shi⁶, Zhiyi Sun¹, Qingqing Liu⁶, Peng Zhang⁷, Wensheng Yan⁸, Yu Wang⁹, Liang Zhang³, Pengfei Li², Xinyuan Li¹⁰, Dingsheng Wang⁵, Penggang Yin⁶, Wenxing Chen¹

Affiliations

¹ Energy & Catalysis Center, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing 100081, China.
² Key Laboratory of Cluster Science Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic, Advanced Research Institute of Multidisciplinary Science, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China.
³ School of Vehicle and Mobility, Center for Combustion Energy, Tsinghua University, Beijing 100084, China.
⁴ Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Science, 1219 Zhongguan West Road, Ningbo 315201, P. R. China.
⁵ Department of Chemistry, Tsinghua University, Beijing 100084, China.
⁶ Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry, Beihang University, Beijing 100191, China.
⁷ Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
⁸ National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, China.
⁹ Shanghai Synchrotron Radiation Facilities, Shanghai Institute of Applied Physics, Chinese Academy of Science, Shanghai 201204, China.
¹⁰ MOE Key Laboratory of Cluster Science, School of chemistry and chemical engineering, Beijing Institute of Technology, Beijing 100081, China.

PMID: 37909679
DOI: 10.1021/acsnano.3c07857

Abstract

The electrochemical nitrogen reduction reaction (eNRR) under mild conditions emerges as a promising approach to produce ammonia (NH₃) compared to the typical Haber-Bosch process. Herein, we design an asymmetrically coordinated p-block antimony single-atom catalyst immobilized on nitrogen-doped Ti₃C₂T_x (Sb SA/N-Ti₃C₂T_x) for eNRR, which exhibits ultrahigh NH₃ yield (108.3 μg h^-1 mg_cat^-1) and excellent Faradaic efficiency (41.2%) at -0.3 V vs RHE. Complementary in situ spectroscopies with theoretical calculations reveal that the nitrogen-bridged two titanium atoms triggered by an adjacent asymmetrical Sb-N₁C₂ moiety act as the active sites for facilitating the protonation of the rate-determining step from *N₂ to *N₂H and the kinetic conversion of key intermediates during eNRR. Moreover, the introduction of Sb-N₁C₂ promotes the formation of oxygen vacancies to expose more titanium sites. This work presents a strategy for single-atom-decorated ultrathin two-dimensional materials with the aim of simultaneously enhancing NH₃ yield and Faradaic efficiency for electrocatalytic nitrogen reduction.

Keywords: Sb−N1C2 moiety; Ti3C2Tx MXene; antimony single atom; asymmetrically coordinated catalyst; nitrogen reduction reaction.