Super-light Cu@Ni nanowires/graphene oxide composites for significantly enhanced microwave absorption performance

Abstract

Graphene oxide (GO) was rarely used as microwave absorption (MA) material due to its lower dielectric loss compared with reduced GO (RGO). However, the characteristics of low conductivity, light weight, and large surface area were beneficial to the impedance matching for absorbers already containing highly conductive metal materials. Cu@Ni nanowires are promising MA materials due to the desired dielectric loss from copper and excellent magnetic loss from nickel. However, the high density was an impediment to its further application. Combining Cu@Ni nanowires with GO should be an effective solution to decrease the absorber’s density and improve its MA properties. Herein, we demonstrated that Cu@Ni nanowires/GO composites exhibited enhanced MA capacities compared with Cu@Ni nanowires or GO alone, and the minimum reflection loss reached −42.8 dB at 16.9 GHz with a thickness of 2.1 mm. The enhanced MA performance mainly originated from good impedance matching, as a result of the addition of low conductivity of GO. To confirm this point, the MA performance of Cu@Ni nanowires/RGO was studied, and unsurprisingly, weak MA performance was obtained. Our work provides a new strategy to decrease the density, broaden the frequency band and tune MA performance of composites.

Microstructural Effects on the Interfacial Adhesion of Nanometer-Thick Cu Films on Glass Substrates: Implications for Microelectronic Devices

“…While the spectra of the Cu films ( Figure 6 a) were similar for all three specimens, showing a mixture of Cu and Cu 2 O; the Cu 2p peaks recorded on the glass side needed an additional peak fit analysis ( Figure 6 b), 40 showing an additional contribution of Cu(OH) 2 in the as-deposited state, which vanished in the annealed state. 41 The chemical composition is identical between both as-deposited runs. From these results, it can be demonstrated that the interface chemistry is similar for the as-deposited and annealed samples and thus does not significantly contribute to the different adhesion energies that were measured.…”

CuCo LDHs Coated CuCoTe Honeycomb‐Like Nanosheets as a Novel Anode Material for Hybrid Supercapacitors

“…All these peaks are suggesting the Cu o and Cu 2+ states of Cu in CTC HLSs owing to the presence of Cu metal and Cu(OH) 2 in the final product. [ 41 ] Co 2p has been split into Co 2p 3/2 (779.94 eV) and Co 2p 1/2 (795.25 eV) (Figure 4d). The satellite peaks of Co 2p 3/2 and Co 2p 1/2 presented at 783.8 and 801.58 eV, respectively.…”

Highly CO Selective Trimetallic Metal-Organic Framework Electrocatalyst for the Electrochemical Reduction of CO2

“…However, their high cost and non-abundance in the earth are regarded as huge disadvantages in terms of their usage for the economical ERC electrode materials [26][27][28]. Recent studies have shown that non noble metals such as Cu and Zn components could be good candidates for the ERC electrode materials because of their high electrocatalytic activity and high abundance in the earth, but it still needs improvement in terms of CO selectivity [29][30][31][32][33][34][35].…”