CdSe/V₂O₅ core/shell quantum dots decorated reduced graphene oxide nanocomposite for high-performance electromagnetic interference shielding application

Abstract

The present work reports nanocomposite of CdSe/V 2 O 5 core-shell quantum dots with reduced graphene oxide (rGO-V-CdSe), as an efficient lightweight electromagnetic wave shielding material, synthesized by a simplistic solvothermal approach. The as-synthesized nanocomposite was analyzed for its structural, compositional and morphological features by x-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy and x-ray photoelectron spectroscopy (XPS). The measurement of complex permittivity/permeability and total shielding efficiency of the as-synthesized samples has been done in a wide frequency range of 8-12 GHz (X-band). Compared to rGO and rGO-CdSe, rGO-V-CdSe nanocomposite exhibits significantly enhanced EMI shielding properties in terms of both dielectric loss and total shielding SE T . The high value of real permittivity (average ε′∼70) and the overall shielding effectiveness up to ∼38 dB have been recorded for rGO-V-CdSe nanocomposite. The studies also infer that the absorption contributes more in total shielding than reflection. The high value of dielectric loss and shielding effectiveness could also be attributed to the presence of various defects leading to dipolar and interfacial polarizations. The excellent EMI shielding properties of the nanocomposite in GHz frequency range (X-band) pave an intuitive way for fabricating a versatile EMI shielding nanocomposite material for applications.

In Situ Fabrication of Activated Carbon from a Bio-Waste Desmostachya bipinnata for the Improved Supercapacitor Performance

“…It gives details of the associated functional groups in the activated carbon material. The appearance of an absorption band at 3115 cm −1 and a small peak at 2368.78 cm −1 owes to −OH stretching vibration of hydroxyl functional groups [10,45,46] . The peak at 1624.63 cm −1 is associated −C=C stretching of the aromatic rings , which may be formed because of the decomposition of C-H bonds to form a more stable -C=C group at higher activation [39,43,[47][48][49] in the as-synthesized activated carbon material, respectively.…”

Fabrication of N-Doped Reduced Graphite Oxide/MnCo2O4 Nanocomposites for Enhanced Microwave Absorption Performance

“…In addition, exposure of EM waves to human beings adversely affects health and leads to many diseases like brain cancer, miscarriage, and leukemia . Therefore, numerous efforts have been made to develop high-performance EM wave shielding materials. − A typical EMI (electromagnetic interference) shield exerts its shielding efficiency (SE) by absorption (SE A ), reflection (SE R ), and multiple internal reflections (SE M ). It may be mentioned that applications of shielding materials, such as metals, carbonaceous materials (carbon nanotube (CNT), graphene, reduced graphite oxide (RGO), carbon nanofiber (CNF)) exhibiting high reflection of incidental EM wave could be limited due to emergence of the passive electromagnetic pollution to the surroundings.…”

Recent Advancement of Electromagnetic Interference (EMI) Shielding of Two Dimensional (2D) MXene and Graphene Aerogel Composites

“…In 2020, the world utilizes electromagnetic radiation as a jamming tool or weapon in battlefields or to destroy electronic components of the ships, radars, and flights, and destroy security of the countries. Hence, electromagnetic interference shielding is the inevitable choice around the globe [9][10][11][12][13][14][15]. So far, scientists have studied EMI shielding in various frequency range by using numerous materials which include zero−dimension (0D), one−dimension (1D), two−dimension (2D), and three−dimension (3D) materials.…”

“…The MXene, MAX phase, quantum dots (QDs) metal nanoparticle, oxide nanoparticle, carbon black, graphene (GN), graphite, single wall carbon nanotube (SWCNT), multiwall carbon nanotube (MWCNT), magnetic nanoparticle, metal oxides, core shell Nano materials, metal plates, organic substances, nonconductive polymers (NCP), conductive polymers (CP), and craft polymers are being utilized for EMI shielding application. Graft and nonconductive polymers are being used as a matrix and used to connect the (0, 1, 2, and 3)−dimensional materials (Table 1) [10][11][12][13][14][15][16][17][18][19]. CPs which act as fillers and help to create different structural feature meanwhile electric conductivity (EC), thermal conductivity (TC), tensile strength, and EMI shielding of the composites also improved substantially.…”

“…[ [10][11][12][13][14][15][16][17][18] EMI shielding can be achieved by absorption (SE A ), reflection (SE R ), and multiple reflection (SE MR ). SE R occurs on the surface whereas SE A and SE MR are happening within the shielding material.…”