Zn-doped SnO_2 nanostructures: structural, morphological and spectroscopic properties

摘要

SnO_2 is a promising material for optoelectronic, catalytic and sensing applications and is highly sensitive to the small amount of impurities that can change its properties drastically. In the present work, co-precipitation method was employed to synthesize pure and Zn-doped SnO_2nanostructures. The effect of Zn doping (1,3 and 5% molar ratio) on crystallographic and spectroscopic properties of SnO_2 nanostructures has been studied. The X-ray diffraction results revealed that SnO_2 possesses tetragonal rutile crystal structure with predominant (110) plane and the same structure was retained after doping with Zn. Raman shifts also confirmed the typical feature of the tetragonal rutile phase in all samples. Fourier transform infrared spectra revealed stretching mode of Sn-O bond and vibra-tional mode of O-Sn-0 bond complementing the Raman spectroscopy results. Field emission scanning electron micrographs confirmed the variation in morphology of synthesized samples with Zn-dopant concentration. High-resolution transmission electron micrographs showed that the synthesized nanostructures were nearly spherical and average particle size varies between ～20-26 nm. UV-Visible results revealed that the band gap of the synthesizedrnSnO_2 nanoparticles increased with increase in Zn content. Photoluminescence spectroscopic results showed that emission intensity increased with increase in Zn content. The increased intensity of emission peaks may be ascribed to the development of defect states in the band gap of Zn-doped SnO_2 nanoparticles.