Acta Phys. -Chim. Sin. ›› 2023, Vol. 39 ›› Issue (10): 2305034.doi: 10.3866/PKU.WHXB202305034

Special Issue: Special Issue on the 30th Anniversary of the Center for Nanochemistry at Peking University

• ARTICLE • Previous Articles     Next Articles

Epitaxial Growth of Unconventional 4H-Pd Based Alloy Nanostructures on 4H-Au Nanoribbons towards Highly Efficient Electrocatalytic Methanol Oxidation

Jie Wang1,2, Guigao Liu2,7, Qinbai Yun3, Xichen Zhou3, Xiaozhi Liu6, Ye Chen8, Hongfei Cheng2, Yiyao Ge3, Jingtao Huang2, Zhaoning Hu2, Bo Chen3, Zhanxi Fan3,4,5, Lin Gu9, Hua Zhang3,4,5,*()   

  1. 1 Key Laboratory of Fluid and Power Machinery of Ministry of Education, School of Materials Science and Engineering, Xihua University, Chengdu 610039, China
    2 Center for Programmable Materials, School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
    3 Department of Chemistry, City University of Hong Kong, Hong Kong, China
    4 Hong Kong Branch of National Precious Metals Material Engineering Research Center (NPMM), City University of Hong Kong, Hong Kong, China
    5 Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, Guangdong Province, China
    6 Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
    7 National Special Superfine Powder Engineering Research Center, School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
    8 Department of Chemistry, The Chinese University of Hong Kong, Hong Kong, China
    9 Beijing National Center for Electron Microscopy and Laboratory of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
  • Received:2023-05-17 Accepted:2023-07-10 Published:2023-07-17
  • Contact: Hua Zhang E-mail:hua.zhang@cityu.edu.hk
  • Supported by:
    the Research Grants Council of Hong Kong(11301721);the Research Grants Council of Hong Kong(TRS(T23-713/22-R)-碳中和);ITC via the Hong Kong Branch of National Precious Metals Material Engineering Research Center (NPMM), and the City University of Hong Kong(9380100);ITC via the Hong Kong Branch of National Precious Metals Material Engineering Research Center (NPMM), and the City University of Hong Kong(7020054);ITC via the Hong Kong Branch of National Precious Metals Material Engineering Research Center (NPMM), and the City University of Hong Kong(9678272);ITC via the Hong Kong Branch of National Precious Metals Material Engineering Research Center (NPMM), and the City University of Hong Kong(7020013);ITC via the Hong Kong Branch of National Precious Metals Material Engineering Research Center (NPMM), and the City University of Hong Kong(1886921)

Abstract:

Direct methanol fuel cells (DMFCs) hold great promise as clean energy conversion devices in the future. Noble metal nanocatalysts, renowned for their exceptional catalytic activity and stability, play a crucial role in DMFCs. Among these catalysts, Pt- and Pd-based nanocatalysts are widely recognized as the most effective catalysts for the electrochemical methanol oxidation reaction (MOR), which is the key half-cell reaction in DMFCs. However, due to the high cost of Pt- and Pd-based materials, there is a strong desire to further enhance their catalytic performance. One of the most promising approaches for it is to develop noble metal-based alloy nanocatalysts, which have shown great potential in improving electrocatalytic activity. Notably, advancements in phase engineering of nanomaterials (PEN) have revealed that noble metal-based nanomaterials with unconventional phases exhibit superior catalytic properties in various catalytic reactions compared to their counterparts with conventional phases. To obtain noble metal-based nanocatalysts with unconventional crystal phases, wet-chemical epitaxial growth has been employed as a facile and effective method, utilizing unconventional-phase noble metal nanocrystals as templates. Nevertheless, epitaxially growing bimetallic alloy nanostructures with unconventional crystal phases remains a challenge, impeding further exploration of their catalytic performance in electrochemical reactions such as MOR. In this study, we utilize 4H hexagonal phase Au (4H-Au) nanoribbons as templates for the epitaxial growth of unconventional 4H hexagonal PdFe, PdIr, and PdRu, resulting in the formation of 4H-Au@PdM (M = Fe, Ir, and Ru) core-shell nanoribbons. As a proof-of-concept application, we investigate the electrocatalytic activity of the synthesized 4H-Au@PdFe nanoribbons towards MOR, which exhibit a mass activity of 3.69 A·mgPd−1, i.e., 10.5 and 2.4 times that of Pd black and Pt/C, respectively, placing it among the best Pd- and Pt-based MOR electrocatalysts. Our strategy opens up an avenue for the rational construction of unconventional-phase multimetallic nanostructures to explore their phase-dependent properties in various applications.

Key words: Phase engineering of nanomaterials, Crystal phase, 4H phase, Pd-based alloy, Methanol oxidation reaction