摘要
高熵合金(HEAs)因其非常规的组成和独特的物理化学性质而得到广泛研究.本文,我们首次提出了一种表面应变策略来调控HEAs的电子结构用于高效的甲醇电氧化反应(MOR).高分辨像差校正扫描透射电子显微镜(STEM)和元素分布分析表明,在Pt Fe CoNi Cu HEAs中各原子分散均匀,并形成FCC晶体结构.700℃热处理所得HEA-700的压缩应变比400℃热处理所得HEA-400的压缩应变高0.94%.正如预期,HEA-700的比活性和质量活性远超HEA-400和目前大多数最先进的催化剂.MOR活性的增强归因于压缩应变导致HEA-700中Pt–Pt键距缩短.同时,核中的非贵金属原子通过转移电子到表面Pt层产生压缩应变和d带中心的下移.这项工作为高性能HEAs电催化剂的设计提供了一个新的视角.
High-entropy alloys(HEAs)have been widely studied due to their unconventional compositions and unique physicochemical properties for various applications.Herein,for the first time,we propose a surface strain strategy to tune the electrocatalytic activity of HEAs for methanol oxidation reaction(MOR).High-resolution aberration-corrected scanning transmission electron microscopy(STEM)and elemental mapping demonstrate both uniform atomic dispersion and the formation of a face-centered cubic(FCC)crystalline structure in Pt Fe Co Ni Cu HEAs.The HEAs obtained by heat treatment at 700℃(HEA-700)exhibit 0.94%compressive strain compared with that obtained at 400℃(HEA-400).As expected,the specific activity and mass activity of HEA-700 is higher than that of HEA-400 and most of the state-of-the-art catalysts.The enhanced MOR activity can be attributed to a shorter Pt–Pt bond distance in HEA-700 resulting from compressive strain.The nonprecious metal atoms in the core could generate compressive strain and down shift d-band centers via electron transfer to surface Pt layer.This work presents a new perspective for the design of high-performance HEAs electrocatalysts.
作者
王东东
陈志文
黃裕呈
李巍
王娟
卢琢乐
顾开智
王特华
吴雨洁
陈晨
张怡琼
黄小青
陶李
董崇禮
陈俊
Chandra Veer Singh
王双印
Dongdong Wang;Zhiwen Chen;Yu-Cheng Huang;Wei Li;Juan Wang;Zhuole Lu;Kaizhi Gu;Tehua Wang;Yujie Wu;Chen Chen;Yiqiong Zhang;Xiaoqing Huang;Li Tao;Chung-Li Dong;Jun Chen;Chandra Veer Singh;Shuangyin Wang(State Key Laboratory of Chemo/Bio-Sensing and Chemometrics,College of Chemistry and Chemical Engineering,Hunan University,Changsha 410082;Department of Materials Science and Engineering,University of Toronto,Toronto ON M5S 3E4;College of Materials Science and Engineering,Changsha University of Science&Technology,Changsha 410114;ARC Centre of Excellence for Electromaterials Science,Intelligent Polymer Research Institute(IPRI),Australian Institute of Innovative Materials(AIIM),University of Wollongong,Wollongong NSW 2522;Research Center for X-Ray Science&Department of Physics,Tamkang University,New Taipei City 25137;College of Chemistry,Chemical Engineering and Materials Science,Soochow University,Suzhou 215123)
基金
supported by the National Natural Science Foundation of China (51402100, 21573066, 21825201, 22002039, and 21522305)
the Scientific Research Foundation of Hunan Provincial Education Department (19C0054)
the Postgraduate Scientific Research Innovation Project of Hunan Province (CX20200441)
the Australian Research Council (CE 140100012)
the Australian National Fabrication Facility | UOW Electron Microscopy Centre, and Compute Canada, Natural Sciences and Engineering Research Council of Canada (NSERC), University of Toronto
