Pranjala Tiwari
Thin Film Laboratory, IIT Roorkee, India
Title: Understanding the structure-property tunability of large area sputtered vertically aligned edge-enriched MoS2 sheets for supercapacitor energy storage application
Biography
Biography: Pranjala Tiwari
Abstract
Insights into the fundamentals of structure-property relations is one of the most important key parameters, which can be utilized for tailoring numerous material properties such as electrical, optical, wettable and electrochemical for photonic, optoelectronic, energy storage and sensing devices. Herein, we report a controlled single-step, large area growth of highly crystalline MoS2 nanoflakes consisting of vertically grown edge exposed layers using DC magnetron sputtering technique. To understand a correlation between microstructural and material properties, we have been prepared the MoS2 of varying thickness (~1 nm – 440 nm). A number of standard characterization techniques such as XRD, XRR, FESEM, Raman spectroscopy, TEM, and XPS, which confirm the formation of vertically aligned nanocrystalline MoS2 films of different thicknesses. Surprisingly, the growth is readily achievable on a variety of insulating as well as conducting substrates and the growth mechanism is discussed in detail. Wettability results manifest that our films could be tuned by varying the layer number as well as the exposed edge sites. We have further made an attempt to augment our prevailing understanding on structure-property relations of MoS2 in order to provide large tunability in the electrical properties. The MoS2 electrical resistance was observed in the range of 15 kΩ – 98 MΩ and displayed an inverse relationship with the number of layers. Further, we have carried out the charge storage measurements and found the three-electrode cell capacitance to be 5.48 mF/cm2 at scan rate of 10 mV/s.