In the long‐running of sulphur hexafluoride (SF6)‐insulated equipment, SF6 inevitably decomposes to various decomposition products under electric discharge, including SOF2 and SO2F2. In this work, single Pt modified molybdenum disulphide (Pt‐MoS2) monolayer, and double Pt modified molybdenum disulphide (Pt2‐MoS2) monolayer are proposed to analyse its adsorption and sensing properties to SOF2 and SO2F2 with single and double gas molecules adsorption based on density functional theory. The adsorption energy, density of states, and molecular orbit theory are employed to analyse the adsorption and sensing mechanism. It turns out that the Pt‐MoS2 and Pt2‐MoS2 present outstanding adsorption capacity to gas molecules. Specifically, double SOF2 adsorption on Pt2‐MoS2 shows the best adsorption performance, and the conductivity of the adsorption system changes the most in the adsorption process. Overall, both Pt‐MoS2 and Pt2‐MoS2 perform as an excellent gas sensor. This study provides a theoretical basis to develop Pt‐MoS2 and Pt2‐MoS2 based materials for SOF2 and SO2F2 detection in SF6‐insulated equipment.

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In this paper, flower-like carbonyl iron powder (CIP) is prepared under normal temperature and pressure by a simple method of chemical reduction. This flower-like morphology is conducive to forming discontinuous network, enhancing diffuse scattering of the incident microwave and polarizing more interface charges. Those are all in favor of electromagnetic wave penetration and absorption. The test results show that compared with the unmodified CIP, the electromagnetic wave absorbing property of flower-like CIP is significantly improved in X-band. It is concluded that this research paves a way to enhance the microwave absorption properties of spherical metal particles.

Reduced graphene oxide (RGO)/Fe nanocomposites were synthesized by a facile one-step reduction reaction, using reduced graphene oxide and FeSO 4 •7H 2 O as raw materials. These RGO/Fe nanocomposites combine Fe nanoparticles with graphene in various thicknesses. The results show that the residual defects and groups in chemically reduced graphene oxide brought about defect polarization relaxation and groups' electronic dipole relaxation, which both make the electromagnetic absorbing performance of RGO/Fe nanocomposites better than that of pure Fe nanoparticles. Most importantly, this paper reveals that graphene with different thicknesses has a great influence on the microwave-absorbing properties of the composites. There was serious agglomeration in RGO/Fe nanocomposites synthesized by thin graphene, while the graphene of a certain thickness could support the nanoparticles on its surface, thereby reducing the effect of agglomeration on the composite material and giving full play to dielectric loss properties of the graphene.

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