Copyright © 2018 American Scientific Publishers All rights reserved Printed in the United States of America Nanoscience and Nanotechnology Letters Vol. 10, 1–9, 2018 Doping Dependent Structural, Optical, Thermal and Catalysis Properties of Synthesized Cadmium Sulfide Nanoparticles W. T. Salam 1† , M. Ikram 1 ∗† , I. Shahzadi 2 , M. Imran 3 4 , M. Junaid 1 , M. Aqeel 1 , S. Anjum 5 , A. Shahzadi 2 , H. Afzal 1 , U. Sattar 1 , A. Asghar 1 , A. Wahab 1 , M. Naz 6 , M. Nafees 1 , and S. Ali 1 7 1 Solar Cell Applications Research Lab, Department of Physics, Government College University Lahore, 54000, Pakistan 2 Punjab University College of Pharmacy, Punjab University, Lahore, 54000, Pakistan 3 Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, 29 Zhongguancun East Road, Haidian District, Beijing 100190, China 4 University of Chinese Academy of Sciences, Beijing 100049, China 5 Department of Physics, COMSATS University Islamabad, Lahore Campus, Lahore 54000, Pakistan 6 Biochemistry Lab, Department of Chemistry, Government College University Lahore, 54000, Punjab, Pakistan 7 Department of Physics, Riphah Institute of Computing and Applied Sciences (RICAS), Riphah International University, 14 Ali Road, Lahore, Pakistan A simple and cost-effective route has been employed to synthesize undoped and copper doped (2, 4 and 6) % cadmium sulfide (CdS) nanoparticles. Resulting materials were characterized by various techniques as XRD results confirmed the formation of hexagonal crystal structure for doped and undoped CdS nanoparticles with crystallite size varying from 11–17 nm calculated by Sherrer equation. The Williamson Hall (W-H) plot is used to examine particle size and lattice strain of pre- pared pure and Cu doped CdS nanoparticles and compared the particle size with Sherrer equation. Moreover, significantly reduced the intensity of diffraction is also evident accompanied by slight peak-shifting towards higher angles. Agglomerated spherical morphology of the CdS nanoparticles with decreasing particle size upon Cu doping was observed by SEM. FTIR spectra was found to consist of stretching vibrations from Cd-S and other related groups with negligible changes in the vibrational modes upon doping. The UV-Vis analysis demonstrates a significant increase in absorption intensity upon doping along with slight blue shift leading to an increased bandgap for doped CdS. The Raman spectroscopy measurement was performed on nanoparticles and thermal properties in different environment were investigated by DSC/TGA. These studies represent a cost- effective way to prepare CdS and related materials with tunable bandgap. This report highlights the effect of bared and various concentrations of Cu doped CdS nanoparticles in the degradation of cationic dye methylene blue by NaBH 4 . Keywords: CdS Nanoparticles, Copper, FESEM, FTIR, Chemical Precipitation Techniques, Methylene Blue. 1. INTRODUCTION It has been commonly observed that the CdS forma- tion as p-type is very challenging mostly due to self- compensation effects because of sulfur vacancies. 1 Many research groups introduced dopants to alter the properties of the inorganic semiconductor to enhance the efficiency of photovoltaic devices. 2 Cadmium sulfide is a group II–VI semiconductor material with a bandgap (B.G) of 2.42 eV ∗ Author to whom correspondence should be addressed. † These two authors contributed equally to this work. in bulk form. It is widely used in applications such as het- erojunction solar cells, laser materials, optoelectronic and photoconductive devices, light emitting diodes, and optical detectors. 3–5 CdS shows n-type conductivity to the intrinsic defects present in it while substitutional doping tends to generate an acceptor level thus changing its conductivity from n-type to p-type. 6 7 In thin-film solar cells, n-type CdS is used as a win- dow material 4 while in bulk-hetero-junction (BHJ) solar cells CdS nanoparticles are incorporated as electron accep- tor materials in the active layer along with electron donor Nanosci. Nanotechnol. Lett. 2018, Vol. 10, No. xx 1941-4900/2018/10/001/009 doi:10.1166/nnl.2018.2839 1