Effect of cobalt concentration on morphology of Co-doped SnO2 nanostructures synthesized by solution combustion method

Abstract

Cobalt (Co) doped SnO2 nanostructures were synthesized by solution combustion synthesis and structural and optical properties were investigated. The morphology of SnO2 nanostructure was changed from nanoflakes to nanospheres via nanorods and crystallite size was reduced from 4.7 nm to 2.7 nm as increase of Co doping concentration. The obvious diffraction peaks of X-ray diffraction and clear lattice fringes confirmed the formation of rutile phase of SnO2. The absorption edge transfers to upper wavelengths and energy bandgap was found to be decreasing by increase of Co concentration. The observed absorption band shows the characteristic band of d–d transitions of Co2+ ions in octahedral site symmetry. Vibrational spectroscopy shows the characteristic absorption peaks of Sn–O and confirms the incorporation of Co ions in SnO2 lattice.