Organic covalent modification to improve thermoelectric properties of TaS2

Organic semiconductors are attracting considerable attention as a new thermoelectric material because of their molecular diversity, non-toxicity and easy processing. The side chains which are introduced into two-dimensional (2D) transition metal dichalcogenides (TMDs) by covalent modification lead to a significant decrease in their thermal conductivity. Here, we describe a simple approach to preparing the side chains covalent modification TaS2 (SCCM-TaS2) organic/inorganic hybrid structures, which is a homogeneous and nondestructive technique that does not depend on defects and boundaries. Electrical conductivity of 3,401S cm(-1) and a power factor of 0.34 mW m(-1) K-2 are obtained for a hybrid material of SCCM-TaS2, with an in-plane thermal conductivity of 4.0 W m(-1) K-1, which is 7 times smaller than the thermal con- ductivity of the pristine TaS2 crystal. The power factor and low thermal conductivity contribute to a thermoelectric figure of merit (ZT) of similar to 0.04 at 443 K.

Automated summary

Organic semiconductors are gaining attention as a thermoelectric material due to their molecular diversity, non-toxicity, and easy processing. This study focuses on covalent modification of two-dimensional transition metal dichalcogenides (TMDs) with side chains, resulting in a significant decrease in thermal conductivity. The researchers developed a simple approach to prepare the modified TaS2 hybrid structure, which exhibits improved electrical conductivity and thermoelectric properties compared to the pristine TaS2 crystal.