A structural study of MoSe2 nanoflakes prepared via liquid phase exfoliation: X ray absorption and photoemission study

Abstract

Two-dimensional materials, particularly transition metal dichalcogenides (TMDs), have garnered significant interest due to their tunable structural and chemical properties when exfoliated to lower dimensions. Exfoliated TMDs have been widely applied across various fields that support the United Nations Sustainable Development Goals (UN-SDGs), especially SDG 7 (Affordable and Clean Energy) and SDG 13 (Climate Action), through their use in energy storage, electrocatalysis, and water treatment membranes. Among TMDs, molybdenum diselenide (MoSe₂) has received comparatively less attention; however, it exhibits outstanding properties similar to those of MoS₂. This study proposes a greener synthesis route for MoSe₂ via liquid-phase exfoliation using an alcohol-based solvent mixture a scalable and cost-effective alternative to conventional methods. Unlike traditional approaches that rely on toxic solvents such as N-methyl-2-pyrrolidone (NMP), our method employs a more environmentally friendly ethanol-water mixture. This eco-conscious process reduces environmental impact while preserving material quality. Comprehensive characterization techniques, including X-ray Absorption Spectroscopy (XAS) and X-ray Photoelectron Spectroscopy (XPS), were employed to investigate the crystallinity, morphology, and composition of the exfoliated MoSe₂. The results highlight the importance of sustainable solvent systems in optimizing exfoliation efficiency and advancing green chemistry principles. By integrating environmentally responsible synthesis with in-depth material analysis, this work contributes to the sustainable development of 2D material production.