Amino acid mediated synthesis of luminescent SnO2 nanoparticles

Tin oxide (SnO2) nanoparticles of average sizes ∼6, ∼16 and ∼33 nm were synthesized successfully by a simple chemical precipitation method using an amino acid, glycine at different calcination temperatures of 200, 400, and 600 °C, respectively. This method resulted in the formation of spherical, polycrystalline SnO2 nanoparticles with a higher degree of monodispersity. The sizes of the SnO2 nanoparticles were found to be a factor of calcination temperature. The synthesized SnO2 nanoparticles have a tetragonal rutile structure. Due to three dimensional quantum confinement effect shown by the synthesized SnO2 nanoparticles in their electronic spectra, an increase in band gap energy (3.85–4.21 eV) is observed with a decrease in particle size (∼33 to ∼6 nm). The synthesized nanomaterials were characterized using X-ray diffraction (XRD), Transmission electron microscopy (TEM), and Fourier transformed infrared spectroscopy (FT-IR). The optical properties were investigated using UV–vis spectroscopy and photoluminescence spectroscopy (PL). Interestingly, the photoluminescence property was shown by the material calcined at 400 °C. The effects of various polar and non-polar solvents on the absorption spectra of the synthesized SnO2 nanoparticles were studied. The plausible reaction mechanism for the formation of SnO2 nanoparticles was also proposed.