Tailoring Phase Transition of Mo-S-Te Ternary System using Heat-Driven Process for Target Functionalities

Abstract

Although structural engineering and phase modulation of transition metal dichalcogenides (TMDs) can be used to implement high-performance optoelectronic devices or energy cells, their expandability combined with individualized optimization for diverse applications using limited TMD materials is still challenging. Herein, we suggest an intriguing strategy to control the target functionalities of the Mo-S-Te ternary system using heat-driven crystallographic selection. The structure and phase alteration of the Mo-S-Te system can be effectively governed by modulating the thermal decomposition temperature, as evidenced by comprehensive spectroscopic and microscopic evaluations. The dual eligibility of the Mo-S-Te ternary system was validated by ascertaining the temperature-dependent selective enhancement of the optoelectronic properties or photoelectrochemical (PEC) performance as compared with those of bare MoS2. The Mo-S-Te synthesized at 300 °C exhibited superior photoresponse dynamics across various wavelengths, indicating its potential for advanced photodetection applications. In field of PEC, Mo-S-Te synthesized at 500 °C was highlighted as a promising photocathode material, offering enhanced PEC reactivity and stability. This study suggests the importance of material characteristics tailored to the synthetic conditions for target applications, which is a promising path to for the expansion of applicability in various areas using a simple approach that utilizes a limited range of TMD materials.