Zeng Xiaojun, Nie Tianli, Zhao Chao, Zhu Guozhen, Zhang Xiaozhen, Yu Ronghai, Stucky Galen D, Che Renchao
Advanced Ceramic Materials Research Institute, School of Materials Science and Engineering, Jingdezhen Ceramic University, Jingdezhen 333403, China.
Institute of Advanced Materials, Jiangxi Normal University, Nanchang 330022, China.
ACS Appl Mater Interfaces. 2022 Sep 14;14(36):41235-41245. doi: 10.1021/acsami.2c12958. Epub 2022 Aug 31.
Constructing the strong interaction between the matrix and the active centers dominates the design of high-performance electromagnetic wave (EMW) absorption materials. However, the interaction-relevant absorption mechanism is still unclear, and the design of ultrahigh reflection loss ( < -80 dB) absorbers remains a great challenge. Herein, CoFe-based Prussian blue (PB) nanocubes are coprecipitated on the surface of ultrathin CoAl-LDH nanoplates with the assistance of unsaturated coordination sites. During the subsequent pyrolysis process, CoAl-LDH serves as a "ligand" providing a Co source and reacts with Fe or C in the CoFe-PB "host" to form stable CoFe alloys or CoC species. As a result, strong reactions emerged between the CoAl-LDH matrix and the active CoFe-CoC@NC centers. Based on the experimental results, the CoAl/CoFe-CoC@NC hierarchical heterostructure delivers good dielectric losses (dipolar polarization, interface polarization, and conductive loss), magnetic losses (eddy current loss, natural resonance, and exchange resonance), and impedance matching, resulting in a remarkable EMW absorption performance with a reflection loss () value of -82.1 dB at a matching thickness of 3.8 mm. Theoretical results (commercial CST) identify that the strong interaction between the 2D CoAl-LDH "ligand" and 2D CoFe-CoC "host" promotes a robust heterointerface among the nanoparticles, nanosheets, and nanoplates, which extremely contribute to the dielectric loss. Meanwhile, the coupling effect of nanosheets and nanoplates greatly contributes to the matching performance. This work provides an aggressive strategy for the effect of ligands and hosts on high-performance EMW absorption.
构建基体与活性中心之间的强相互作用主导着高性能电磁波吸收材料的设计。然而，与相互作用相关的吸收机制仍不明确，设计超高铁损（<-80 dB）吸收体仍然是一个巨大的挑战。在此，基于钴铁的普鲁士蓝（PB）纳米立方体在不饱和配位点的辅助下共沉淀在超薄钴铝层状双氢氧化物（CoAl-LDH）纳米片表面。在随后的热解过程中，CoAl-LDH作为一种“配体”提供钴源，并与CoFe-PB“主体”中的铁或碳反应形成稳定的钴铁合金或碳化钴物种。结果，在CoAl-LDH基体与活性CoFe-CoC@NC中心之间出现了强烈反应。基于实验结果，CoAl/CoFe-CoC@NC分级异质结构具有良好的介电损耗（偶极极化、界面极化和传导损耗）、磁损耗（涡流损耗、自然共振和交换共振）以及阻抗匹配，在3.8 mm的匹配厚度下产生了显著的电磁波吸收性能，反射损耗（）值为-82.1 dB。理论结果（商业CST）表明，二维CoAl-LDH“配体”与二维CoFe-CoC“主体”之间的强相互作用促进了纳米颗粒、纳米片和纳米板之间形成强大的异质界面，这极大地有助于介电损耗。同时，纳米片和纳米板的耦合效应极大地有助于匹配性能。这项工作为配体和主体对高性能电磁波吸收的影响提供了一种积极的策略。
