SYNTHESIS OF 2D SEMICONDUCTOR FOR SENSING and SUPERCAPACITOR APPLICATIONS

Abstract

Throughout the entire history of mankind, number of significant progresses in science, engineering and technology have been introduced. These technological progresses such as energy production (hydroelectric, nuclear and thermal), industrial revolution and advances in transportation (automobiles, trains, aircraft, etc.), communication systems (mobiles, internet and satellites) and supercomputers are resort to improve the quality of human life. Even if, all these are quite differ from one another but still have something common. These are the materials which mark as milestones of such technologies as well as their limitations. For example, the communication system, industries of transport have massively benefited with the revolutionary development of safer, stronger, lighter and more efficient materials. Still, these materials poses some obstruct in supersonic transportation as well as in space. The general discoveries of ameliorating these materials have led us through various stages of human developments. These novel technologies may not come to fruition without discoveries and innovations in the development of such nanoscale materials. Almost all the materials are composed of tiny particles, which in turn consist of many atoms, usually visible or invisible to nude eye depending on their size. The conventional materials contain grains varying in size from few microns (µm) to millimeters (mm). A nanometer (nm) is much smaller dimension than µm and mm. The term nano originated from the Greek word nanos means dwarf which referred to the length scale of one billionth of a meter. The average size of an atom is of the order of 1 to 2Å in radius and hence in one nm, there may be 3-5 atoms, depending on the atomic radii. Nanocrystalline material has grains in the order of 1-100 nm. Figure 1.1 depicts the partial list of zero dimensional nanostructures with their typical range of dimensions [13]. For comparison, a red blood cell is approximately 7,000 nm wide, a single human hair is about 100,000 nm wide