Enhanced Yield and Compatibility of Exfoliated MoS2 through Iodine‐Assisted Thermal Treatment of Powders
Nikolaos Chalmpes, Michael A. Susner, Michael Velez, Ahmed Wasel Alsmaeil, Ali Jawaid, Richard A. Vaia, Emmanuel P. GiannelisAbstract
This study introduces iodine‐assisted thermal annealing of commercially sourced molybdenum disulfide (MoS₂) powders to significantly enhance their dispersion yield, exfoliation efficiency, and compatibility across a wide range of solvents. This method leverages iodine as a transport agent during annealing (800–1200 °C), leading to the removal of oxide and sulfide impurities that impede exfoliation and reduce swelling, such as those that bridge individual layers. Dispersions of the post‐treated MoS2 powder outperform alternative approaches such as surfactant‐assisted dispersion, redox dispersion, or lithium intercalation; here, stable colloidal solutions are produced with yields exceeding 50% where the dispersion is dominated by exfoliated single‐to‐few layer flakes. This is achieved without the need for surface additives or use of extreme mechanical forces that can degrade performance of MoS2 in electronic, sensor, and optical applications. These findings, which highlight the impact of composition and structural purity of the starting powders, offer a promising solution for expanding the use of layered transition metal dichalcogenide materials.