Facile approach for a robust graphene/silver nanowires aerogel with high-performance electromagnetic interference shielding

Abstract

Robust graphene/silver nanowires (AgNWs) hybrid aerogels were fabricated by facile processes including mixing directly, reducing, and ambient pressure drying. The mechanical properties and electromagnetic interference (EMI)-shielding performance of the resultant hybrid aerogels were investigated in detail. Because silver nanowires with a high aspect ratio have been acting as crosslinkers to bridge twodimensional graphene sheets, a highly porous and electrically conducting framework can resist high external loading to prevent major deformation and act as an express way for electron transport.Consequently, the hybrid aerogel exhibits large mechanical strength of 42 kPa, 35 times larger than that of the neat reduced graphene oxide aerogel (1.2 kPa), which can resist great damage. More importantly, the as-prepared aerogel possesses high EMI-shielding performance of up to $45.2 dB due to its unique nanostructure and good electrical properties. These results indicate that graphene/AgNWs hybrid aerogel prepared using this simplified method promises to be an ideal functional component for mechanically robust and high-performance EMI-shielding nanocomposites. † Electronic supplementary information (ESI) available. See Fig. 1 (a) Schematic illustration of fabrication process of AgNWs/GO hybrid aerogel and corresponding digital photos; (b), (c) typical SEM and TEM images of GO and AgNWs individually; (d) SEM images of composite aerogel at different magnifications. 28 | RSC Adv., 2019, 9, 27-33 This journal isFig. 4 EMI-shielding performances of RGO/AgNWs aerogel with different mass ratios in the frequency range from 8.2 to 12.4 GHz: (a) SE T , (b) SE A , (c) SE R ; (d) average EMI-SE values from (a), (b), (c).30 | RSC Adv., 2019,9,[27][28][29][30][31][32][33] This journal is

Lightweight Cellulose Nanofibril/Reduced Graphene Oxide Aerogels with Unidirectional Pores for Efficient Electromagnetic Interference Shielding

“…The C 1s peak can be further fitted into three subpeaks including C−H/C−C, C−O, and C=O, whose binding energy is 285, 287, and 288.3 eV, respectively (Figure 4e,f). [ 31 ] Compared to u‐CNF 1 /GO, the C−O peak of u‐CNF 1 /rGO shows a lower intensity, confirming the decrease in oxygen‐containing components. [ 32 ]…”

“…[ 30 ] The I D / I G decreases after reduction, which is explainable by the repair of the defects created by oxygen‐containing groups. [ 31 ] And the I D / I G decreases with the temperature increasing, indicating the degree of reduction of GO increases.…”

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

“…The findings clearly indicate that tan δ ε increases with increasing filler loading (GO) in the nanocomposites and is found to be the highest in Ag/RGO-3. This is probably due to the formation of a conductive network between Ag and RGO, a uniform distribution of Ag, conductivity, dipolar polarization arising from RGO functionalities, electric polarization, and multiple interfacial polarization in Ag/RGO nanocomposites. ,,,, The presence of an incomplete semicircle (as an arc) in the Cole–Cole plot for Ag/RGO-3 shown in Figure d could be attributed to the Debye dipolar relaxation and conductive loss causing electromagnetic waves on the conductive materials. ,,, …”

“…Recently, carbon-based materials, such as carbon black, carbon nanofibers, carbon nanotubes, graphene, graphene oxide (GO), and reduced graphene oxide (RGO) have attracted extensive attention as EMI-shielding materials. ,− Among these, GO provides a hydrophilic surface comprising a large number of negatively charged oxygen-containing functional groups available for the strong electrostatic interactions with positively charged metal ions . An Ag/GO composite provides favorable properties, such as low density, good dispersion, corrosion resistance, electrical conductivity, easy processing, and synergistic effects. ,− Additionally, the properties of Ag decorated on RGO nanocomposites also received much attention due to its wide range of applications in the field of sensing, catalysis, heavy metal detection, optoelectronics, EMI shielding, and as an antibacterial agent. , Therefore, combining carbonaceous materials with Ag is considered a right approach for the formation of their nanostructured composites for achieving effective EMI shielding. ,,− …”

“…Aepuru et al fabricated Ag/3D graphene aerogels by the freeze-casting method and observed an EMI SE of about ∼32 dB in the X-band range. In another work, an RGO/Ag NW aerogel was prepared by a high temperature reflux (140 °C)/freezing method with an EMI SE of ∼45.2 dB . Ag/graphene hybrids prepared electrochemically exhibited an EMI SE of up to 29.9 dB (thickness: 0.257 mm) .…”