In recent years, semiconductor nanomaterials have been extensively studied and reports are available for their preparation methods, physical and chemical properties of nanoparticles and their characterization techniques. Because of their potential applications, ZnS nanoparticles are recently major area of research. It is an important inorganic material for a variety of applications including photoconductors, solar cells, field effect transistors, sensors, transducers optical coatings and light-emitting materials. Inorganic nano-particles have found potential application in various electronic devices. Synthesis, shape and size control are important issues for nano-particles research. Various nano-structured materials have found potential applications in optical and electrical devices such as photoconductors, LEDs, solar cells, field effect transistors, optical coatings etc. ZnS has wide band gap ranging from 3.5 to 3.8 eV at room temperature and the band gap can be tuned in the UV region by controlling the size of the nano-particles. In the present work we have studied the synthesis of ZnS nano-particles, their characterization to investigate various properties such as size, structure, band gap and luminescence via different characterization tools. The particles were then used as acceptors for fabrication of organic hybrid solar cells.