Enhanced Supercapacitor Performance and Electromagnetic Interference Shielding Effectiveness of CuS Quantum Dots Grown on Reduced Graphene Oxide Sheets

Abstract

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–1 at 1 A g–1 current density with moderate cycling stability (∼60.3% after 1000 cycles at 10 A g–1). 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.

Solar Desalination via Multilayers of Transparent Photothermal Fe3O4@Cu2–xS Thin Films

“…Figure 5 a shows the FTIR spectra of Fe 3 O 4 @Cu 2– x S/PMMA film with 85% AVT. As shown in this figure, the film characteristically exhibits the peaks at 1728, 1435, 1147, 605, and 548 cm −1 , which respectively correspond to CO, CH 3 , CO bonds of PMMA and CuS, FeO bonds in Fe 3 O 4 @Cu 2– x S. [ 35–37 ] These FTIR peaks confirm the Fe 3 O 4 @Cu 2– x S nanoparticles in the matrix of PMMA. The XRD patterns of both Fe 3 O 4 and Fe 3 O 4 @Cu 2– x S nanoparticles are shown in Figure 5b.…”

Room-Temperature One-Step Synthesis of Silver/Reduced Graphene Oxide Nanocomposites as an Excellent Microwave Absorber

“…The total EMI shielding (SE T ) of a material is attributed to the degree of attenuation of propagating electromagnetic radiation. SE T can be described as a ratio of power (intensity) of transmitted radiation ( P T ) to incident radiation ( P I ). , …”

“…The SE T follows three basic mechanisms: (a) reflection of radiation from the front face of the shield (reflection-shielding effectiveness, SE R ), (b) absorption of radiation as it propagates through the shield’s thickness (absorption-shielding effectiveness, SE A ), and (c) multiple reflections from different interfaces of a material (multiple reflection-shielding effectiveness, SE M ) . Hence, SE T is represented as follows …”

Polymer Composites with Quantum Dots as Potential Electrode Materials for Supercapacitors Application: A Review

“…Hydrothermal method is also used to prepare CuO quantum dots via using copper (II) acetate monohydrate precursor and additionally single layer graphene was added on the CuO quantum dot surface for better structural stability (unique core-shell structure) and improved performance [57]. Likewise, CuS, SnO 2 , NiCo 2 O 4 quantum dots were also produced using copper (II) dithiooxamide, stannous chloride dehydrate, nickel acetate tetra-hydrate and cobalt acetate tetra-hydrate precursors respectively [58][59][60]. In order to synthesize WS 2 and MoS 2 QDs, solvothermal technique is been broadly used [61].…”