文献类型：期刊文献

英文题名：The cation exchange driving multi-phase regulation in Co7Fe3/Co@NC for enhanced broadband electromagnetic wave absorption

作者：Zhou, Xingyue[1];Wu, Xiaohan[1];Li, Siyue[1];He, Yu[1];Wang, Ruoqi[1];Rao, Siyu[1];Zhuang, Qixin[1];Zhou, Yukang[1];Liu, Xiaoyun[1];Zuo, Peiyuan[1]

机构：[1]East China Univ Sci & Technol, Sch Mat Sci & Engn, Shanghai 200237, Peoples R China

年份：2024

卷号：230

外文期刊名：CARBON

收录：;EI(收录号：20243616974381);WOS:【SCI-EXPANDED(收录号:WOS:001386055900001)】；

基金：All authors are grateful for financial support from the National Natural Science Foundation of China (52373073, 52303083, 52073091, 22171086) , Shanghai Pujiang Program (22PJ1402500) and the Key Laboratory of Advanced Polymeric Materials of Shanghai.

语种：英文

外文关键词：Phase engineering; Cation exchange reaction; Electromagnetic parameters; Impedance matching; Heterogeneous structures

摘要：Phase engineering offers distinctive advantages in designing efficient electromagnetic wave (EMW) absorbers. The manipulation of the interaction and arrangement of different multi-phase systems enables the achievement of more precise EMW absorption. However, the transition mechanism from single metal phases to metal/alloy phases has not yet been fully revealed. Here, we employ multiphase engineering driven by cation exchange reactions to finely control the proportion of Co/Co7Fe3 phases and regulate electromagnetic parameters. The introduction of cavities and heteroatoms through cation exchange enables optimized defect distribution and composition, which enhances both impedance matching and electromagnetic attenuation capabilities. Specifically, we yield hollow Co7Fe3/Co@N-doped carbon (H-Co7Fe3/Co@NC) embedded in high-crystallinity graphite carbon after high-temperature pyrolysis, which promotes significant electron transfer between phases, thus enhancing conduction and polarization losses. H-Co7Fe3/Co@NC exhibits ultra-strong reflection loss (RL) of -59.70 dB at 9.37 GHz and achieves broadband absorption of 6.01 GHz at 2.1 mm. This study highlights the influence of Co7Fe3/Co heterogeneous structures on absorption performance and validates the electromagnetic response mechanism of multi-phase heterostructures through COMSOL finite element simulation analysis. Thus, this work paves the way for applying multi-phase engineering driven by cation exchange reactions for advanced absorbers.