摘要:电子信息技术的发展对微波吸收材料(MAMs)提出了更高要求,其有效集成多种功能以满足各类复杂场景的实际应用需求,将成为未来发展方向。本文,烟台大学杜伟 教授、侯传信 教授、山东大学刘峣 教授等在《Chemical Engineering Journal》期刊发
1成果简介
电子信息技术的发展对微波吸收材料(MAMs)提出了更高要求,其有效集成多种功能以满足各类复杂场景的实际应用需求,将成为未来发展方向。本文,烟台大学杜伟 教授、侯传信 教授、山东大学刘峣 教授等在《Chemical Engineering Journal》期刊发表名为“Hollow multiphase cobalt sulfide nanospheres/rGO aerogels with sulfur vacancy and heterogeneous interfaces for optimized microwave absorption, thermal insulation, flame retardation, and supercapacitor performance”的论文,研究在富含缺陷与异质界面的还原氧化石墨烯(rGO)气凝胶基底上,实现了空心多相硫化钴(CoS, Co₉S₈, Co₃S₄)纳米球原位生长。所制备的复合材料凭借特殊空心纳米结构与多孔气凝胶的协同效应、CoS/Co9S8/Co3S4/rGO间广泛的异质界面以及热场刺激引入的硫空位,在低厚度条件下实现了6.16 GHz的最大有效吸收带宽(EABmax),几乎完全覆盖Ku波段和X波段。同时通过雷达散射截面(RCS)模拟验证了复合材料的实际应用价值。
此外,其卓越的隔热与阻燃性能确保了微波吸收体(MA)在高温及电磁干扰(EMI)环境下的整体可靠性。此外,制备的CoxSy/rGO复合材料作为超级电容器电极,展现出卓越的电化学性能:在1.0 A g⁻¹条件下实现1023.3 F g⁻¹的高比容量,并在10.0 A g⁻¹循环5000次后仍保持近100%库仑效率。本研究为开发兼具微波吸收特性及其他多功能特性的硫化钴基复合材料指明了发展方向。
2图文导读
图1. Influence of solvothermal reaction time on the structural properties of CSX. Samples of CSX system: (a1) preparation flowchart; (a2) schematic of morphology evolution; (b1-b3) SEM images, (c) XRD spectra, (d) EPR spectrograms; (e) electromagnetic parameters, and (f) α-curves. (g) Schematic of wave absorption by hollow cobalt sulfide nanospheres in the heterophase of CS2. (h1−h3) Im and (i1-i3) three-dimensional performance plots of the CSX samples.
图2. (a) Preparation flowchart of RCS2-Y system samples; (b) XRD spectra of RCS2-Y and rGO samples. (c) Close-up schematic of aerogel; (d) N2 adsorption isotherm and (e) BJH pore size distribution for RCS2–12. (f) Raman curves of RCS2-Y and rGO samples. (g) XPS spectra of RCS2–12, high resolution XPS spectra of (h) S 2p, (i) Co 2p, (g) C 1 s, (k) O 1 s.
图3. (a-c) SEM images; (d) HR-TEM images; (e) crystal modeling maps; (f) TEM image; (g) HAADF and EDS mapping images of RCS2–12.
图5. (a-c) RL/tm/Z-f curves for the RCS2-Y, (d) comparison of EAB and RLmin values, (e) EAB of RCS2–12 in the range of 2.0–3.1 mm in the X and Ku bands, (f) comparison of wave-absorbing properties of this experimental samples with cobalt sulfide-based EWAMs.
图6. Schematic diagram of the mechanism of composite aerogel samples regarding absorbing EMWs.
图7. (a) Optical images of ultralight RCS2–12 aerogel standing on dandelion seeds. (b, c) Tests of thermal insulation capacity of RCS2–12 with rGO. (d) Tests of flame-retardant capacity of polyethylene foam monoliths; (e) polyethylene foam stacked with RCS2–12 aerogel.
图8. (a-c) CV, GCD, EIS curves for rGO samples; (d-f) CV, GCD, EIS curves for composites; (g) CV curves at different scanning rates, (h) GCD curves at different current densities, and (i) cycling performance and coulombic efficiency for RCS2–12 samples.
3小结
本文通过溶剂加热、冷冻干燥和碳化工艺,合成了具有硫空位和异质界面的多相空心硫化钴纳米球(CoS, Co₉S₈, Co₃S₄)/rGO气凝胶。其卓越的电磁吸收性能归因于形态调控、缺陷工程与异质界面的三元协同作用,实现了吸收带宽(Im)与衰减能力的协同优化,从而增强电磁波吸收效果。最佳复合材料在2.2毫米厚度下展现出6.16GHz的有效吸收带宽(EAB),基本覆盖整个Ku波段;在3.0毫米厚度下EAB达3.84GHz,基本覆盖整个X波段。通过电磁仿真验证了其潜在实用价值。实验结果表明制备的CoxSy/rGO兼具隔热、阻燃与储能特性。本研究为开发多功能高效磁吸附材料提供了新思路。
文献:
来源:材料分析与应用
来源:石墨烯联盟