Low-temperature electrical conductivity of composite film formed by carbon nanotubes with MoS2 flakes

Abstract

Multifunctional composite nanosystems containing both one-dimensional and two-dimensional nanostructures possess improved electrical, mechanical, and thermal properties which offer a wide range of applications. In this work, the composite films formed by single-walled carbon nanotubes and MoS2 flakes (MoS2-SWNTs) are studied exploiting Raman spectroscopy, scanning electron microscopy, and low-temperature conductivity measurements (5–312 K). The MoS2-SWNTs and SWNTs films demonstrate the semiconductor behavior with negative temperature coefficient of resistance. The temperature dependence of the composite film resistance in the range of 5–204 K is considered whithin the framework of Mott model that describes the motion of electrons with variable range hopping due to thermally activated tunneling (3D Mott VRH model). At T > 204 K, the temperature dependence of composite film resistance was fitted by the Arrhenius-like equation. The empirical parameters included in two transport models were evaluated. The comparison between the composite and SWNTs films shows that the conductivity of the composite is mostly determined by nanotubes.