Work

Scalable Bottom‐Up Synthesis of High‐Purity 1T‐MoS 2 Assisted by Na 2 SO 4 Template

Year: 2025

Type: article

Abstract: MoS 2 is a promising layered material for energy storage fields owing to its phase‐dependent physicochemical properties. However, the scalable synthesis of 1T‐MoS 2 is challenging due to the inherently high generation energy. Inspired by alkali‐metal‐induced phase transitions of 2H‐MoS₂, we developed a sodium‐mediated synthesis strategy using Na 2 SO 4 as the phase transition inducer, growth template and S source for the bottom‐up synthesis of 1T‐MoS 2 . Theoretical calculations showed that the distortion of Mo─Mo and Mo─S bonds and the change of the formation energy of 2H‐ and 1T‐MoS 2 caused by the adsorption of electron donating Na were the fundamental reasons for the formation and stability of octahedral 1T‐MoS 2 . In situ analysis confirmed that Na 2 SO 4 guided the epitaxial growth of MoS 2 by slowly releasing H 2 S, and the formation of intermediates NaMoO x and NaMoS x were the key to the generation of 1T phase. Systematic optimization identified 16‐18 vol% hydrogen concentration as the critical parameter for achieving high‐phase‐purity metallic MoS₂. As a catalyst for hydrogen evolution reaction, the overpotential and Tafel slope of 1T‐MoS 2 is 37.4 mV and 32.2 mV/dec, respectively. This preparation strategy enables large‐scale production of metastable MoS 2 while maintaining exceptional crystallinity and phase purity, providing new opportunities for phase engineering of transition metal dichalcogenide.

Source: Small

DOI: 10.1002/smll.202500529