Studies on two dimensional molybdenum disulfide mo based heterojunction photocatalytic materials towards energy and environmental application

Abstract

newlineThe problems regarding environmental pollution and energy shortage due to the newlinedepletion of fossil fuels is becoming the two biggest challenges in the new century with newlinea growing industry as well as the population. The consumption of fossil fuels greatly newlineaffects the greenhouse effect by emitting CO2. So in order to settle these problems and newlineto achieve a greener world, photocatalysis is considered as the Holy Grails of green and newlinesustainable technology towards the conversion of solar energy into chemical energy newlinelike water splitting, N2 reduction, and CO2 photoreduction, environmental remediation newlineand energy storage. However, for the efficient utilization of solar energy, the choice of newlinea novel photocatalyst is very much important. Very recently nanostructured 2D newlinesemiconductor photocatalyst has triggered a reawakening of interest in the field of newlineenergy and environmental applications due to the unprecedented optical as well as newlineelectronic properties and high surface to volume ratio. Among a large array of 2D newlinesemiconductor photocatalyst 2D-MoS2 has been flourishing the significant impact in newlinethe field of photocatalysis due to the presence of its basal as well as edge active sites, newlineexcellent absorption property in the UV-Vis-IR region and high mobility of charge newlinecarriers etc. Especially in the thesis I have thoroughly fabricated 2D-MoS2 material newlinewith different morphology applying the various reaction conditions and after it, I have newlineprepared various MoS2 based p-n heterojunction composite by taking other low-cost newlinevisible light active metal sulfide material like ternary metal chalcogenides. The newlinestructural, optical, and morphological properties of the as-synthesized photocatalyst has newlinebeen characterized through various characterization technique. Through the newlineexperimental procedure, the as-fabricated 2D-MoS2 based thiospinel p-n heterojunction newlinephotocatalyst exhibited an excellent photocatalytic activity towards the energy newlinevi newlineconversion like H2 evolution and N2 reduction to ammonia and the pollutant abatement newlinelike phenol degradation. The extraordinary photocatalytic activity is mainly attributed newlineto the formation heterojunction at the interface of two semiconductors through S-S newlinelinkage which provides space charge region for the efficient separation as well as the newlinemigration of photogenerated charge carriers. newlineDue to the enormous demand for effective conversion of solar energy and large-scale newlinehydrogen production, cost-effective and long-lasting photocatalysts are bel