Ghosh Kalyan, Srivastava Suneel Kumar
Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
ACS Omega. 2021 Feb 5;6(7):4582-4596. doi: 10.1021/acsomega.0c05034. eCollection 2021 Feb 23.
This study is focused on the preparation of the CuS/RGO nanocomposite via the hydrothermal method using GO and Cu-DTO complex as precursors. X-ray diffraction, Fourier-transform infrared spectroscopy, and Raman and X-ray photoelectron spectroscopy study revealed the formation of the CuS/RGO nanocomposite with improved crystallinity, defective nanostructure, and the presence of the residual functional group in the RGO sheet. The morphological study displayed the transformation of CuS from nanowire to quantum dots with the incorporation of RGO. The galvanostatic charge/discharge curve showed that the CuS/RGO nanocomposite (12 wt % Cu-DTO complex) has tremendous and outperforming specific capacitance of 3058 F g at 1 A g current density with moderate cycling stability (∼60.3% after 1000 cycles at 10 A g). The as-prepared nanocomposite revealed excellent improvement in specific capacitance, cycling stability, Warburg impedance, and interfacial charge transfer resistance compared to neat CuS. The fabricated nanocomposites were also investigated for their bulk DC electrical conductivity and EMI shielding ability. It was observed that the CuS/RGO nanocomposite (9 wt % Cu-DTO) exhibited a total electromagnetic shielding efficiency of 64 dB at 2.3 GHz following absorption as a dominant shielding mechanism. Such a performance is ascribed to the presence of interconnected networks and synergistic effects.
本研究聚焦于以氧化石墨烯（GO）和铜 - DTO 配合物为前驱体，通过水热法制备硫化铜/还原氧化石墨烯（CuS/RGO）纳米复合材料。X 射线衍射、傅里叶变换红外光谱、拉曼光谱和 X 射线光电子能谱研究表明，形成了具有改善结晶度、缺陷纳米结构且还原氧化石墨烯片层中存在残余官能团的 CuS/RGO 纳米复合材料。形态学研究显示，随着还原氧化石墨烯的引入，硫化铜从纳米线转变为量子点。恒电流充放电曲线表明，CuS/RGO 纳米复合材料（12 wt%铜 - DTO 配合物）在 1 A g 电流密度下具有高达 3058 F g 的优异比电容，且具有适度的循环稳定性（在 10 A g 下 1000 次循环后约为 60.3%）。与纯硫化铜相比，所制备的纳米复合材料在比电容、循环稳定性、Warburg 阻抗和界面电荷转移电阻方面均有显著改善。还对制备的纳米复合材料的体直流电导率和电磁干扰屏蔽能力进行了研究。结果表明，CuS/RGO 纳米复合材料（9 wt%铜 - DTO）在 2.3 GHz 时以吸收作为主要屏蔽机制，总电磁屏蔽效率达到 64 dB。这种性能归因于相互连接的网络结构和协同效应。
