Fast site-to-site electron transfer of high-entropy alloy nanocatalyst driving redox electrocatalysis

• Published in: Nature communications Vol. 11; no. 1; p. 5437
• Main Authors: Li, Hongdong, Han, Yi, Zhao, Huan, Qi, Wenjing, Zhang, Dan, Yu, Yaodong, Cai, Wenwen, Li, Shaoxiang, Lai, Jianping, Huang, Bolong, Wang, Lei
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 28.10.2020; Nature Publishing Group; Nature Portfolio
• Subjects: 639/301/299/886; 639/638/563/979; 639/638/77/884; 639/925/357/354; Alloys; Catalysts; Electrocatalysts; Electron transfer; Entropy; High entropy alloys; Humanities and Social Sciences; Hydrogen evolution reactions; Low temperature; Methanol; multidisciplinary; Nanoalloys; Nanoparticles; Oxidation; Redox reactions; Reduction; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-020-19277-9

Designing electrocatalysts with high-performance for both reduction and oxidation reactions faces severe challenges. Here, the uniform and ultrasmall (~3.4 nm) high-entropy alloys (HEAs) Pt 18 Ni 26 Fe 15 Co 14 Cu 27 nanoparticles are synthesized by a simple low-temperature oil phase strategy at atmospheric pressure. The Pt 18 Ni 26 Fe 15 Co 14 Cu 27 /C catalyst exhibits excellent electrocatalytic performance for hydrogen evolution reaction (HER) and methanol oxidation reaction (MOR). The catalyst shows ultrasmall overpotential of 11 mV at the current density of 10 mA cm −2 , excellent activity (10.96 A mg −1 Pt at −0.07 V vs. reversible hydrogen electrode) and stability in the alkaline medium. Furthermore, it is also the efficient catalyst (15.04 A mg −1 Pt ) ever reported for MOR in alkaline solution. Periodic DFT calculations confirm the multi-active sites for both HER and MOR on the HEA surface as the key factor for both proton and intermediate transformation. Meanwhile, the construction of HEA surfaces supplies the fast site-to-site electron transfer for both reduction and oxidation processes. The design of nanostructured catalysts plays a key role in the electrocatalytic redox reaction performances. Here, authors prepared uniform and small-sized high-entropy alloy PtNiFeCoCu nanoparticles that showed improved activities for H 2 evolution methanol oxidation reactions.