Dynamical investigation of tunable magnetism in Au@Ni-carbide nanocrystals by a combined soft and hard X-ray absorption spectroscopy

作     者：Weifeng Huang Jianxin Kang Tingwen Chen Dawei Pang Lihua Wang Hang Wei Changchun Yang Dongfeng Zhang Lin Guo Weifeng Huang;Jianxin Kang;Tingwen Chen;Dawei Pang;Lihua Wang;Hang Wei;Changchun Yang;Dongfeng Zhang;Lin Guo

作者机构：College of Chemistry and Chemical EngineeringInner Mongolia UniversityHohhot 010021China School of Electronic EngineeringJiujiang UniversityJiujiang 332005China School of ChemistryBeihang UniversityBeijing 100191China Institute of Microstructure and Property of Advanced MaterialsBeijing University of TechnologyBeijing 100124China 

出 版 物：《Nano Research》 (纳米研究（英文版）)

年 卷 期：2022年第15卷第5期

页      面：4320-4326页

核心收录：

学科分类：07[理学] 070205[理学-凝聚态物理] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 0702[理学-物理学] 

基　　金：This work was supported by the National Natural Science Foundation of China(NSFC Nos.21801140 51532001 51667009 21771014 and 52002010)。 

主　　题：X-ray absorption spectroscopy soft X-ray absorption spectroscopy carbide nickel carbonation process magnetism 

摘      要：Nickel based magnetic nanocrystals have been widely applied in magnetic and catalytic facilities.Tunable magnetic properties of nickel can be easily obtained via non-magnetic doping or phase transformation.However,phase transformation from face centered cubic(fcc)to hexagonal close packed(hcp)induced magnetism adjustment of Ni are always confused with nickel carbide(Ni_(3)C),due to the similar atomic structures of hcp-Ni and Ni3C.Here,we present series of Au@Ni-carbide magnetic materials achieved from the controlled carbonation of Au@Ni core-shell structures,whose magnetism is tunable by adjusting the amount of carbon in the Ni layer.Ex-situ hard X-ray absorption spectroscopy(XAS)at the metal K edge and soft XAS at both metal L edge and carbon K edge provide solid evidence for the carbonation process from fcc-Ni to Ni_(x)C,rather than phase transformation to hcp-Ni.Further investigation reveals that the magnetism of the hybrids is mainly contributed from the residual fcc-Ni.The result represents an accurate and effective way to distinguish hexagonal Ni_(3)C from hcp-Ni,and provides the pathway to control magnetism of Ni-based materials for applications.