Ultralight Magnetic and Dielectric Aerogels Achieved by Metal-Organic Framework Initiated Gelation of Graphene Oxide for Enhanced Microwave Absorption

Xiaogu Huang; Jiawen Wei; Yunke Zhang; BinBin Qian; Qi Jia; Jun Liu; Xiaojia Zhao; Gaofeng Shao

doi:10.1007/s40820-022-00851-3

Ultralight Magnetic and Dielectric Aerogels Achieved by Metal-Organic Framework Initiated Gelation of Graphene Oxide for Enhanced Microwave Absorption

Nanomicro Lett. 2022 Apr 19;14(1):107. doi: 10.1007/s40820-022-00851-3.

Authors

Xiaogu Huang¹, Jiawen Wei², Yunke Zhang², BinBin Qian^{3

4}, Qi Jia⁵, Jun Liu⁵, Xiaojia Zhao⁶, Gaofeng Shao⁷

Affiliations

¹ Institute of Advanced Materials and Flexible Electronics (IAMFE), School of Chemistry and Materials Science, Nanjing University of Information Science and Technology, Nanjing, 210044, People's Republic of China. hxg@nuist.edu.cn.
² Institute of Advanced Materials and Flexible Electronics (IAMFE), School of Chemistry and Materials Science, Nanjing University of Information Science and Technology, Nanjing, 210044, People's Republic of China.
³ Department of Chemical and Biological Engineering, Monash University, Victoria, 3800, Australia.
⁴ School of Chemistry and Environmental Engineering, Yancheng Teachers University, Yancheng, 224002, People's Republic of China.
⁵ College of Field Engineering, Army Engineering University of PLA, Nanjing, 210007, People's Republic of China.
⁶ Hebei Key Laboratory of Inorganic Nano-Materials, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
⁷ Institute of Advanced Materials and Flexible Electronics (IAMFE), School of Chemistry and Materials Science, Nanjing University of Information Science and Technology, Nanjing, 210044, People's Republic of China. gfshao@nuist.edu.cn.

Abstract

Metal-organic frameworks (MOFs) are used to directly initiate the gelation of graphene oxide (GO), producing MOF/rGO aerogels. The ultralight magnetic and dielectric aerogels show remarkable microwave absorption performance with ultralow filling contents. The development of a convenient methodology for synthesizing the hierarchically porous aerogels comprising metal-organic frameworks (MOFs) and graphene oxide (GO) building blocks that exhibit an ultralow density and uniformly distributed MOFs on GO sheets is important for various applications. Herein, we report a facile route for synthesizing MOF/reduced GO (rGO) aerogels based on the gelation of GO, which is directly initiated using MOF crystals. Free metal ions exposed on the surface of MIL-88A nanorods act as linkers that bind GO nanosheets to a three-dimensional porous network via metal-oxygen covalent or electrostatic interactions. The MOF/rGO-derived magnetic and dielectric aerogels Fe₃O₄@C/rGO and Ni-doped Fe₃O₄@C/rGO show notable microwave absorption (MA) performance, simultaneously achieving strong absorption and broad bandwidth at low thickness of 2.5 (- 58.1 dB and 6.48 GHz) and 2.8 mm (- 46.2 dB and 7.92 GHz) with ultralow filling contents of 0.7 and 0.6 wt%, respectively. The microwave attenuation ability of the prepared aerogels is further confirmed via a radar cross-sectional simulation, which is attributed to the synergistic effects of their hierarchically porous structures and heterointerface engineering. This work provides an effective pathway for fabricating hierarchically porous MOF/rGO hybrid aerogels and offers magnetic and dielectric aerogels for ultralight MA.

Keywords: Gelation mechanism; Magnetic and dielectric aerogels; Metal–organic frameworks; Microwave absorption; Radar cross-sectional simulation.