Synthesis of mixed metal oxide nanoparticles of SnO2 with SrO via sol–gel technology: their structural, optical, and electrical properties

Abstract

Mixed metal oxides of tin with strontium (xSnO2.SrO) in different molar ratio {where x = 1 (1), 2 (2), 4(3); SnO2 doped with Sr+2(4), SnO2 doped with Sr+2 and co-doped with F−(5)} have been prepared by sol–gel technology in basic medium using SnCl2.2H2O as precursor in isopropanol as solvent. Structural analysis by XRD patterns have shown formation of particles at nanoscale and phase separation of SnO2 in tetragonal rutile framework in these mixed metal oxides. This fact was further supported by TEM. SEM images of all these samples have shown formation of various geometrical patterns ranging from spherical particles to nanorods. In the IR spectra of all these oxides, Sr–O absorption bands were present only in sample (1). UV–Vis spectroscopy has shown reduction in optical band gap in mixed metal oxides and the lowest value of band gap was observed for sample (3). Photoluminescence spectra of all these derivatives are found to be almost similar again indicated retention of tetragonal rutile SnO2 framework. I–V curves of all these oxides are non-linear and lowest resistance was observed for sample (3). This fact was further supported by impedance measurements.