Lee, Jong-Young Kim, Jong Hun Jung, Yeonjoon Shin, June Chul Yangjin, Lee Kim, Kwanpyo Kim, Namwon van der Zande, Arend M. Son, Jangyup Lee, Gwan-Hyoung 2024-01-19T14:30:51Z 2024-01-19T14:30:51Z 2021-10-21 2021-07 2662-4443 https://pubs.kist.re.kr/handle/201004/116817 Desulfurization of MoS2 alters its chemical and physical properties by breaking structural symmetry. Here, the atomic-scale mechanistic pathway by which this occurs is investigated during plasma etching, and changes in chemical structure and physical properties are revealed. Structural symmetry-breaking is a key strategy to modify the physical and chemical properties of two-dimensional transition metal dichalcogenides. However, little is known about defect formation during this process. Here, with atomic-scale microscopy, we investigate the evolution of defect formation in monolayer MoS2 exposed indirectly to hydrogen plasma. At the beginning of the treatment only top-layer sulfur atoms are removed, while vacancies and the molybdenum atomic layer are maintained. As processing continues, hexagonal-shaped nanocracks are generated along the zigzag edge during relaxation of defect-induced strain. As defect density increases, both photoluminescence and conductivity of MoS2 gradually decreases. Furthermore, MoS2 showed increased friction by 50% due to defect-induced contact stiffness. Our study reveals the details of defect formation during the desulfurization of MoS2 and helps to design the symmetry-breaking transition metal dichalcogenides, which is of relevance for applications including photocatalyst for water splitting, and Janus heterostructures. English SPRINGERNATURE Evolution of defect formation during atomically precise desulfurization of monolayer MoS2 Article 10.1038/s43246-021-00185-4 1 Communications Materials, v.2, no.1 Communications Materials 2 1 Y scopus 000681390800002 2-s2.0-85118880642 Materials Science, Multidisciplinary Materials Science Article HYDROGEN EVOLUTION SULFUR VACANCIES THERMOELECTRIC PROPERTIES 2-DIMENSIONAL MATERIALS CATALYTIC-ACTIVITY PHOTOLUMINESCENCE FRICTION MoS2 Hydrogen plasma Desulfurization Defect