Dual emissive Sn (12x) Cu x Co x O 2 nanostructures – A correlation study of doping concentration on structural, optical and electrical properties P. Baraneedharan a , C. Siva a , A. Saranya b , R. Jayavel b , K. Nehru c , M. Sivakumar a,⇑ a Division of Nanoscience and Technology, Anna University, BIT Campus, Tiruchirappalli 620 024, India b Centre for Nanoscience and Technology, Anna University, Chennai 600 025, India c Department of Chemistry, Anna University, BIT Campus, Tiruchirappalli 620 024, India article info Article history: Received 23 October 2013 Received in revised form 20 December 2013 Accepted 30 December 2013 Available online 23 January 2014 Keywords: Doping Peak shift Absorption edge Oxygen vacancies abstract A simplistic chemical co-precipitation route was adapted to synthesize Sn (12x) Cu x Co x O 2 (x = 0, 0.01 and 0.03) nanoparticles. The structural studies were carried out using X-ray diffraction pat- tern and the shift in diffraction peak, lattice constant and particle size with doping concentration was determined. The morphology of nanoparticles with an average size of 13–18 nm was observed using high-resolution transmission electron microscopy. A signifi- cant increase in the absorption edge with an increase in doping concentration was observed using ultraviolet-visible absorption spectroscopy. Further, the blue-shifted band gap value was plotted using Tauc’s relation. The near-band-edge emission at 3.9 eV and the deep-level-emission at 2.4 eV were systematically examined by photoluminescence spectroscopy. The dependence of doping concentration on temperature-reliant electrical conductivity was examined using DC electrical measurements. A meticulous explo- ration on diffraction peak shift, the Burstein-Moss shift, the mech- anism for dual emission and the decreased electrical conductivity in Sn (12x) Cu x Co x O 2 nanostructures were further discussed. Ó 2014 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.spmi.2013.12.029 0749-6036/Ó 2014 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. E-mail address: muthusiva@gmail.com (M. Sivakumar). Superlattices and Microstructures 68 (2014) 66–75 Contents lists available at ScienceDirect Superlattices and Microstructures journal homepage: www.elsevier.com/locate/superlattices