Angelw: new progress in preparation, structural analysis and basic physical properties of metastable phase MoS2 of Shanghai Silicate Institute

The layered transition metal sulfide, represented by MoS 2, is a two-dimensional material new star after graphene It has a series of strange physical characteristics, such as adjustable semiconductor electronic structure, high carrier mobility, quantum spin Hall effect and valley magnetoelectric effect, which has aroused great interest of scientists Monolayer or sublayer MoS 2 can be widely used in the development of next generation FET, photodetector, sensor and other high-performance nano devices There are many different crystal structures of MoS 2, including 2h, 3R, 1t 'and 1t equivalence 1t 'and 1t MoS 2 are metal phase, which have good conductivity and excellent performance in energy storage such as electrocatalytic hydrogen production, lithium battery, sodium battery and super capacitor However, they are all thermodynamic metastable phases, which are easily transformed into 2H phase under high temperature and laser irradiation Therefore, the preparation of pure phase 1t 'and 1tmos2 is very challenging Recently, the research group of photoelectric conversion materials and devices, Shanghai Institute of silicate, Chinese Academy of Sciences, superconducting center of Shanghai Institute of Microsystem and information technology, and Beijing University of chemistry have cooperated to research Firstly, limos 2 crystal with high crystallinity was synthesized by high temperature solid phase strategy, and then limos 2 was treated by saturated acetonitrile iodine solution 1t MoS 2 crystal was prepared for the first time The chemical driving force produced by this process makes Li ion escape from the interlayer of molybdenum disulfide, while the octahedral coordination mode of molybdenum is still maintained, and finally a crystal with good crystallinity can be obtained At the same time, the crystal structure of 1t MoS 2 with superconductivity has been resolved for the first time Relevant research results were published in the international famous journal angel Chem Int.ed (DOI: 10.1002 / ange 201710512) under the title of "structure re determination and superconductivity observation of bulk 1t MoS 2" The first co authors of the paper are Fang Yuqiang and pan Jie, graduate students of Shanghai Silicate Institute, and the co correspondents are Huang Fuqiang, researcher Lin Tian, associate researcher, and Mou Gang, associate researcher The research results further reveal the novel physical properties of the metastable phase of MoS 2, and expand its research and application in the field of condensed matter physics and new energy (a) 1t MoS 2 powder XRD (b) 1t MoS 2 Raman spectrum (c) HAADF-STEM image of 1t MoS 2 (d) the resistance of 1t MoS 2 varies with temperature under different magnetic fields (source: Shanghai Institute of silicate, Chinese Academy of Sciences) 1t MoS 2 prepared according to the existing methods In recent years, the research group of photoelectric conversion materials and devices has developed a high-quality limos 2 crystal by stripping high-temperature solid-state synthesis to obtain high-purity 1t / 1t'mos 2 Nano chips or even single crystal materials This method has been extended to the preparation of other transition metal disulfide nanoflakes, such as NbS2, TAS 2, tis 2, etc The above series of research work has been supported by the national key research and development plan, the National Natural Science Foundation, the Chinese Academy of Sciences and the Shanghai Municipal Science and Technology Commission Corresponding author: researcher Huang Fuqiang, associate researcher Lin Tianquan, associate researcher Mou Gang