Abstract:

BiCuXO (X=S, Se, Te), a layered oxide material, has garnered significant attention due to its exceptional electrical transport properties and inherently low thermal conductivity, positioning it as a prospective candidate for high-performance thermoelectric applications. The optimization of material physical properties is intrinsically linked to an in-depth investigation of the crystallographic properties. This study initially presents a meticulous account of the growth procedures for BiCuXO crystals, elucidating the enhancement of electrical transport characteristics through the modulation of carrier concentrations via growth methodologies and elemental doping. A comparative analysis with ceramic samples documented in the literature is also provided. Subsequently, the paper delves into the electrical and thermal transport properties of BiCuXO crystals. The electrical transport properties encompass conductive behavior, scattering mechanisms, and magnetic resistance evolution. The thermal transport performance is mainly studied through inelastic neutron scattering and Raman experiments, combined with first principles calculations to investigate the physical mechanism of its extremely low thermal conductivity. The paper culminates with an exposition on the application of BiCuSeO crystals in photothermal electricity, harnessing the thermoelectric effect. By summarizing the growth methodologies of BiCuXO crystals and examining their electrical, thermal, and photothermal properties, this paper endeavors to offer theoretical insights and experimental guidance for the enhancement of BiCuXO material performance.

Key words: BiCuSeO, crystal growth, thermoelectric performance, electricity transportation, thermal conductivity, photothermoelectric effect