8:15 AM - QN02.09.02
Tungsten Disulfide (WS2) Hexagonal Nanosheets—Surfactant-Free Synthesis, Characterization and Applications
Poonam Sharma1,Jayanta Chakraborty1,Siresha Bankuru1,Sreeraj Puravankara1,Ananya Kumar1
Currently, a wide range of potential applications ranging from electronics to catalysis (including modern transistors,1 photo emitting devices,2 solar cells,3 hydrogen storage,4 catalysis,5, 6 lubricants,7 Li-ion batteries,8 and supercapacitors9) are depended on two-dimensional (2D) materials.10, 11 Till date, graphene has been proved best thin layer two-dimensional (2D) material due to its various fascinating properties such as high carrier mobility, good mechanical flexibility, and lower dimension related properties. Recently, graphene is replacing by others 2D materials due to the absence of band gaps and low absorption capacity of light, limits its application in modern electronic devices. Beyond graphene, transition metal dichalcogenides (TMDCs) have been proved their importance in these fields due to tuneable energy band gaps, layered structure, flexible optical, mechanical, and electrical behaviors. Among various TMDCs, WS2 and MoS2 behave like a semimetallic graphene and interesting materials to examine their properties.
Hence, we have developed a novel method for the synthesis of surfactant-free hexagonal WS2 nanosheets using a wet chemical method. Large-scale syntheses (yield = 97 %) were also carried out and obtained good crystalline and pure WS2 that was confirmed by XRD, FESEM-EDX, and TEM analysis. A temperature and pH-dependent studies were performed to optimize the synthesis process. Prepared highly crystalline hexagonal WS2 nanosheets were tested for various applications such as a lubricant, as a counter electrode in solar cell and as an anode in batteries. A detailed reaction mechanism was studied using Uv-Visible and FTIR spectroscopy.
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