Synthesis of 2H/fcc‐Heterophase AuCu Nanostructures for Highly Efficient Electrochemical CO2 Reduction at Industrial Current Densities

• Published in: Advanced materials (Weinheim) Vol. 35; no. 51; pp. e2304414 - n/a
• Main Authors: Zhou, Xichen, Zhang, An, Chen, Bo, Zhu, Shangqian, Cui, Yu, Bai, Licheng, Yu, Jinli, Ge, Yiyao, Yun, Qinbai, Li, Lujiang, Huang, Biao, Liao, Lingwen, Fu, Jiaju, Wa, Qingbo, Wang, Gang, Huang, Zhiqi, Zheng, Long, Ren, Yi, Li, Siyuan, Liu, Guangyao, Zhai, Li, Li, Zijian, Liu, Jiawei, Chen, Ye, Ma, Lu, Ling, Chongyi, Wang, Jinlan, Fan, Zhanxi, Du, Yonghua, Shao, Minhua, Zhang, Hua
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.12.2023; Wiley
• Subjects: bimetallic nanostructures; Carbon dioxide; Carbon monoxide; Catalysis; Chemical reduction; CO2 reduction reaction; Crystal defects; Current density; Electrocatalysts; Fourier transforms; Grain boundaries; heterophase; Infrared reflection; Infrared spectroscopy; Intermetallic compounds; in‐situ FTIR; MATERIALS SCIENCE; Nanomaterials; Nanostructure; phase engineering of nanomaterials; Spectrum analysis; Stacking faults; Structural engineering; Synthesis; Twin boundaries
• DOI: 10.1002/adma.202304414
• ISSN: 0935-9648

Structural engineering of nanomaterials offers a promising way for developing high‐performance catalysts toward catalysis. However, the delicate modulation of thermodynamically unfavorable nanostructures with unconventional phases still remains a challenge. Here, the synthesis of hierarchical AuCu nanostructures is reported with hexagonal close‐packed (2H‐type)/face‐centered cubic (fcc) heterophase, high‐index facets, planar defects (e.g., stacking faults, twin boundaries, and grain boundaries), and tunable Cu content. The obtained 2H/fcc Au99Cu1 hierarchical nanosheets exhibit excellent performance for the electrocatalytic CO2 reduction to produce CO, outperforming the 2H/fcc Au91Cu9 and fcc Au99Cu1. The experimental results, especially those obtained by in‐situ differential electrochemical mass spectroscopy and attenuated total reflection Fourier‐transform infrared spectroscopy, suggest that the enhanced catalytic performance of 2H/fcc Au99Cu1 arises from the unconventional 2H/fcc heterophase, high‐index facets, planar defects, and appropriate alloying of Cu. Impressively, the 2H/fcc Au99Cu1 shows CO Faradaic efficiencies of 96.6% and 92.6% at industrial current densities of 300 and 500 mA cm−2, respectively, as well as good durability, placing it among the best CO2 reduction electrocatalysts for CO production. The atomically structural regulation based on phase engineering of nanomaterials (PEN) provides an avenue for the rational design and preparation of high‐performance electrocatalysts for various catalytic applications. 2H/fcc‐heterophase AuCu hierarchical nanostructures, i.e., Au99Cu1 and Au91Cu9, are synthesized via a facile one‐pot wet‐chemical method. The obtained 2H/fcc Au99Cu1 hierarchical nanosheets show superior performance of electrochemical CO2 reduction toward the CO production at industrial current densities due to the unique structural features, including unconventional 2H/fcc heterophase, high‐index facets, planar defects, and appropriate alloying of Cu.