ISSN: 2319-8753 International Journal of Innovative Research in Science, Engineering and Technology (An ISO 3297: 2007 Certified Organization) Vol. 3, I ssue 3, March 2014 Copyright to IJIRSET www.ijirset.com 10670 Microwave assisted synthesis of CdS nanoparticles for structural and optical Characterization Shiv Kumar Choubey 1 , K.P.Tiwary 2* Teaching cum Research Fellow, Dept. of ECE, Birla Institute of Technology, Patna Campus, India 1 Asst. Professor, Dept. of Applied Physics, Birla Institute of Technology, Patna Campus, India 2 Abstract: The nanoparticles of CdS were successfully synthesized by Microwave assisted irradiation method. CdS materials can be used for the fabrication of solar cells, nonlinear optical materials, optoelectronic and electronic devices. X-ray diffraction (XRD) and scanning electron microscopy (SEM) technique were used for structural and morphological characterization of nanoparticles of CdS. XRD characterization of nanoparticles were taken which verify the crystalline form. The average size of the nanocrystallites were measured by Debye-Scherrer formula as per the XRD spectrum and the particle size lies in the range 4 - 7 nm. The optical characterization of the nanoparticles of CdS were taken by UV-Visible absorption spectra and the optical bandgap of as synthesized CdS nanoparticles were found to be 3.8 eV. KEYWORDS: Microwave, XRD, bandgap, nanoparticles * Corresponding Author I. INTRODUCTION II-VI compound semiconductors such as ZnS, CdS, CdSe, etc., are promising materials for technological application, mostly due to their large band gap. In recent years there has been increased interest in the scientific and technological aspects of the nanosized semiconductors. Semiconductor nanocrystals have received much attention recently due to their size dependent optical properties and and their applications as light emitting diode, phosphors in lighting, displays, solar cell, X-ray sensors, photocatalyst and electrochemical cell [1-5]. Semiconductor nanomaterials are of great interests for both fundamental research and industrial development. II-VI semiconductor nanocrystals have been synthesized by a variety of methods which include solvothermal method, co-precipitation method, sol-gel process, chemical bath deposition method and microwave irradiation method [6-9]. The formation of high quality nanocrystals can be achieved by controlling the thermodynamics and kinetics during the nucleation and its growth [10]. Water has a very high dipole moment and that is why it is one of the best solvent for microwave assisted reaction [11]. During the formation of the nanoparticles under microwave irradiation, solvents can have an important influence on the size and morphology of the final products. Among II-VI semiconductors, CdS is a widely used substance with many advanced technological application. It is one of the most studied materials with a direct band gap of 2.42 eV. By controlling the size of the nanoparticles, it is possible to design a material of required magnetic, elastic and optical properties. In different solvents, the collision rate between reactant molecules, the heating rate, and the temperature of the reaction are different [12]. Microwave heating results from the interaction of the electromagnetic wave with the irradiated medium which produce a force on charged particles and cause them to rotate or further polarized. In this paper we report the synthesis of CdS nanoparticles by microwave assisted methods and their optical characterization.