Single and Few Layered WS2 Nanoflowers: Synthesis, Characterization and Their Piezoresponce

Two Dimensional (2D) transition metal dichalcogenides (TMDS) plays an emerging key potential applications in optoelectronics, electronic devices, sensors, batteries, supercapacitors, biomedicine and electrocatalytic and photocatalysis owing its wide range of chemical, electrical and mechanical properties. Until now, a wide range of synthesis approaches have been developed for the preparation of single or few-layered TMD hybrid nanostructures, which can be synthesized directly from both physical and chemical vapor depositions. Here we demonstrate the single and few layered tungsten disulfide (WS 2 ) as synthesized by solvothermal method. The morphologies of WS 2 were recorded by field emission scanning electron microscopy (SEM), the size of the Nanoflowers ranges from 400-600nm. The XRD pattern shows a crystalline hexagonal structure. All the diffraction peaks could be indexed to the p63/mmc space group, JCPDS no. 08-0237. To further revel the layered charactertistics, HRTEM and XPS spectra was collected. The piezoresponse force microscopy (PFM) image reveals that the WS 2 nanoflowers exhibits a significantly piezoelectric potential up to 12mV. The WS 2 exhibited significantly piezoresponse, which may result from the single and fewlayers due to its noncentrosymmetric structure. The unique piezoelectric property of the crystalline WS 2 nanoflowers is opening up the new field applications such as low-power consumption of logic-circuit switchers, and ultrasensitive biological sensors, and piezoelectric nanogenerators.