Seeded Synthesis of Unconventional 2H-Phase Pd Alloy Nanomaterials for Highly Efficient Oxygen Reduction

Yiyao Ge; Xixi Wang; Biao Huang; Zhiqi Huang; Bo Chen; Chongyi Ling; Jiawei Liu; Guanghua Liu; Jie Zhang; Gang Wang; Ye Chen; Lujiang Li; Lingwen Liao; Lei Wang; Qinbai Yun; Zhuangchai Lai; Shiyao Lu; Qinxin Luo; Jinlan Wang; Zijian Zheng; Hua Zhang

doi:10.1021/jacs.1c08973

Seeded Synthesis of Unconventional 2H-Phase Pd Alloy Nanomaterials for Highly Efficient Oxygen Reduction

J Am Chem Soc. 2021 Oct 20;143(41):17292-17299. doi: 10.1021/jacs.1c08973. Epub 2021 Oct 6.

Authors

Yiyao Ge¹, Xixi Wang¹, Biao Huang^{1

2}, Zhiqi Huang¹, Bo Chen¹, Chongyi Ling³, Jiawei Liu⁴, Guanghua Liu⁵, Jie Zhang⁵, Gang Wang⁶, Ye Chen⁶, Lujiang Li¹, Lingwen Liao¹, Lei Wang⁷, Qinbai Yun¹, Zhuangchai Lai¹, Shiyao Lu¹, Qinxin Luo¹, Jinlan Wang³, Zijian Zheng⁷, Hua Zhang^{1

2

8}

Affiliations

¹ Department of Chemistry, City University of Hong Kong, Hong Kong, China.
² Hong Kong Branch of National Precious Metals Material Engineering Research Center (NPMM), City University of Hong Kong, Hong Kong, China.
³ School of Physics, Southeast University, Nanjing 211189, China.
⁴ Center for Programmable Materials, School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore.
⁵ State Key Laboratory of New Ceramics & Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
⁶ Department of Chemistry, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China.
⁷ Laboratory for Advanced Interfacial Materials and Devices, Institution of Textiles and Clothing, Research Institute for Smart Energy, & Research Institute of Intelligent Wearable Systems, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, China.
⁸ Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, China.

PMID: 34613737
DOI: 10.1021/jacs.1c08973

Abstract

Crystal phase engineering of noble-metal-based alloy nanomaterials paves a new way to the rational synthesis of high-performance catalysts for various applications. However, the controlled preparation of noble-metal-based alloy nanomaterials with unconventional crystal phases still remains a great challenge due to their thermodynamically unstable nature. Herein, we develop a robust and general seeded method to synthesize PdCu alloy nanomaterials with unconventional hexagonal close-packed (hcp, 2H type) phase and also tunable Cu contents. Moreover, galvanic replacement of Cu by Pt can be further conducted to prepare unconventional trimetallic 2H-PdCuPt nanomaterials. Impressively, 2H-Pd₆₇Cu₃₃ nanoparticles possess a high mass activity of 0.87 A mg^-1_Pd at 0.9 V (vs reversible hydrogen electrode (RHE)) in electrochemical oxygen reduction reaction (ORR) under alkaline condition, which is 2.5 times that of the conventional face-centered cubic (fcc) Pd₆₉Cu₃₁ counterpart, revealing the important role of crystal phase on determining the ORR performance. After the incorporation of Pt, the obtained 2H-Pd₇₁Cu₂₂Pt₇ catalyst shows a significantly enhanced mass activity of 1.92 A mg^-1_Pd+Pt at 0.9 V (vs RHE), which is 19.2 and 8.7 times those of commercial Pt/C and Pd/C, placing it among the best reported Pd-based ORR electrocatalysts under alkaline conditions.