A new family of two-dimensional (2D) materials, tellurene, composed only by group-VI element tellurium, were recently predicted theoretically and verified experimentally. The most stable phase of monolayer tellurene adopts the 1T-MoS 2 -like structure with the space group P3̅ m1. The predicted multivalency character and ditch-rich surface structure imply tellurene might be a good substrate for alkali atom adsorption and therefore be used as anode materials for lithium-or sodium-ion batteries. We performed systematic theoretical studies on the adsorption and diffusion behaviors of lithium and sodium atoms on monolayer tellurene. The theoretical volumetric capacity is estimated to be around 900 mAh cm −3 . The low diffusion barrier of 0.123 eV and the low expansion ratio of 11.86% suggest that multivalency and a ditch-rich surface might be propitious for high-performance electrode materials design.

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In this study, a method for testing the aging of silicone rubber insulators using terahertz waves in the 0.17–0.22 THz frequency band is proposed, aiming at the problem of online non-destructive testing of the aging degree of composite insulators. The relationship between the aging degree of silicone rubber composite insulators and the relative dielectric constant was studied through first-principles calculations and molecular chain scission models. In addition, the electromagnetic model of the terahertz signal incident on the silicon rubber sheet was simulated and the relationship between the aging degree of the silicon rubber and the terahertz input return loss was obtained. Eleven insulator samples with different degrees of aging were selected. In these samples, the degree of aging was calibrated according to the degree of surface deterioration and the average partial discharge voltage. The terahertz return loss measurement experiment was performed after that. Finally, the results of experiment and calculation simulation were compared and the reliability of the relationship between the aging degree of the silicone rubber insulator and the terahertz input return loss was verified.

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