Transition metal sulfide two-dimensional nanomaterials are another important type of two-dimensional semiconducting nanomaterials after graphene. In particular, it can be seen that the tunable bandgap characteristic in the near infrared band has unique advantages in developing new photoelectric functional devices. Recently, Wang Jun, a researcher at the CAS Key Laboratory of High Power Laser Materials, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, made a number of progresses in the preparation, characterization and nonlinear optical properties of two-dimensional semiconductor materials. Aiming at the bottleneck of transition metal sulfide nanomaterials in the process of device formation: The synthesis of low-cost, large-size two-dimensional materials, the research team (Zhang Xiaoyan et al.) Designed and synthesized the special morphology Molybdenum disulfide (MoS2) nano-film. The solvothermal method breaks through the traditional hydrothermal synthesis technology to get only the limitations of the micron-scale layered nanosheets. The "organic solvent-water" system is used to grow in situ on various substrates such as quartz, silicon wafer, optical fiber and curved surface Continuous, large size, shape control MoS2 film. The results show that the third-order nonlinear absorption coefficient of the MoS2 thin film with multi-stage structure in the near infrared region is much higher than that of the MoS2 thin film deposited by the vacuum suction-resurfacing deposition technique, which is attributed to its Unique hierarchy. Related papers have been published online by Nanoscale magazine [Nanoscale, 8, 431 (2016)]. The structural microscopic analysis of two-dimensional nanomaterials is of great significance for the study of the physical properties and deviceization of such materials. Based on this, the research team (Li Yuanxin) et al. Proposed a method to simulate the optical contrast of two-dimensional layered nanomaterials by using the optical transmission feature matrix, and studied the dependence on the wavelength between the substrate and incident light. Using this method, the contrast of different layers of MoS2 prepared by chemical vapor deposition under white light irradiation is calculated. The theoretical simulation is in good agreement with the experimental results. Compared with the traditional Fresnel theory, this method is quicker and more accurate, which can effectively guide the selection of two-dimensional nanomaterials substrate and irradiation light source. Related papers have been published online by Nanoscale magazine (DOI: 10.1039 / C5NR06287J). The research group (Dong Ningning et al.) Also systematically studied the visible-near-infrared broadband optical limiting effect of two-dimensional nanostructured liquid-phase transition metal sulfide nanoparticles under the action of nanosecond pulsed laser. Studies have shown that in the near infrared band, selenides have better optical limiting properties than sulfides. Based on the liquid dispersion system, a new method to calculate the number density of nanosheets is proposed. The relationship between laser energy and scattering center size is established. It is very important to study the optical limiting effect induced by Mie scattering in transition metal sulfur compounds. A related paper was published in Scientific Reports, 5, 14646. Working with Trinity College Dublin, Ireland, the research group (Zhang Sai-feng et al.) Validated the broadband ultra-fast nonlinear optical effect of the new two-dimensional material, black phosphorus, and confirmed its superior saturation absorption characteristics over graphene. Phosphorus in the development of mode-locked and Q-switched devices on the potential. The paper was published in Nature communications [Nature communications, 6, 8563, (2015)] and was highly praised and cited by research groups such as Nanyang Technological University and Wroclaw University of Technology, as well as Phys.org and MIT Technology Review, It is the first report on the absorption effect of saturating black phosphorus. In addition, the group's special paper Tunable nonlinear refractive index of two-dimensional MoS2, WS2, and MoSe2 nanosheet dispersions, published in Photonics Research in 2015, was selected as the Top Ten Papers Published in 2015 by Photonics Research Magazine. Fig.1 A large-scale, multi-layered MoS2 nanofilm grown in situ on a variety of substrates Figure 2 Structural parameters of two-dimensional material modulation of optical contrast Fig.3 Optical Limiting Effect and Theoretical Calculation of Transition Metal Sulfur Compounds Nanosheets Figure 4 black phosphorus high-resolution TEM and saturation absorption characteristics Smart Electric Scooter has smart app can control the electric scooter and has a forward-thinking design that inspires and moves, just as it moves you ahead. Strong yet lightweight The sturdy frame is made of aerospace-grade aluminum, which has a low density and high structural strength. Yongkang Mysail Technology Co., Ltd. , https://www.mysail-scooter.com