Study of thermoelectric properties of tungsten silicides
Abstract
This work presents a comprehensive investigation of the temperature-dependent electrical and thermal transport properties of tungsten silicides, including mono-, di-, and higher-order phases. A comparative analysis of experimental data is performed with particular emphasis on electronic structure, charge-carrier characteristics, and phase-dependent transport behavior. The results indicate that di- and higher-order tungsten silicides exhibit semiconductor-like properties, with electrical resistivities in the range of 50–85 μΩ·cm at 300 K. Nuclear magnetic resonance spectroscopy was employed to examine the local electronic environment of tungsten atoms and their interaction with surrounding silicon nuclei, revealing structural imperfections such as defects, grain boundaries, and secondary-phase inclusions that influence charge transport. The temperature dependences of electrical conductivity, thermal conductivity, Seebeck coefficient, and thermoelectric quality factor were systematically studied over the temperature range of 300–800 K. The analysis demonstrates that higher-order tungsten silicides exhibit the most favorable thermoelectric characteristics among the investigated phases, highlighting their potential for use in high-temperature thermoelectric energy conversion and sensing applications, as well as their promise for further optimization through controlled doping strategies.