LAUSR

Abstract Topological insulators exhibit a new variety of unusual phenomena associated with topologically protected gapless surface states. Interestingly, most topological insulators are possibly outstanding electromagnetic shielding materials due to the easily adjustable electric transport performance, which is controlled by regulating nanostructures based on conducting surface states. Herein, a series of Sb2Te3 nanosheets with different thicknesses were prepared by a hydrothermal method. The electrical conductivity increases as the thickness of the topological nanosheet decreases, so the nanosheet aggregates exhibit an extraordinary electromagnetic response behavior different from metallic materials, which is conducive to achieving ultra-thin electromagnetic shielding. Moreover, Sb2Te3 nanosheet aggregates show a positive temperature coefficient (PTC) of electrical conductivity that it increases monotonically with increasing temperature in the entire range of 313-573 K. The effect of PTC implies that the longitudinal conductance plays a dominant role in Sb2Te3 nanosheet aggregates. An equivalent circuit model is proposed to describe the unique electrical conductance behavior of nanosheet aggregates for topological insulators. The outstanding electromagnetic shielding performance and positive temperature correlation make Sb2Te3 nanosheets emerging in next-generation electronic equipment and aerospace applications in high-temperature environments.