Synthesis and properties of (Ni, Al) co-doped nanoparticles

Pure and (Ni, Al) co-doped SnO2 nanoparticles are prepared using the chemical co-precipitation method. In this procedure SnCl2 center dot 2H(2)O, NiCl2 center dot 6H(2)O and AlCl2 act as precursor elements. The aqueous NH4OH and Poly Ethylene Glycol (PEG) are precipitate agent and stabilizing agent respectively. Pure samples and those doped with different concentration of Ni (1, 3, 5 mol%) with Al kept as constant at 5 mol% are grown. The, pH value, reaction time and reaction temperatures are optimized during synthesis. The X-ray diffraction (XRD) patterns indicate the formation of single phase tetragonal structure of pure and co-doped (Ni, Al) SnO2 nanoparticles. From XRD calculations, the sizes of the pure and (Ni, Al) co-doped nanoparticles yield the range of 10-20 nm. The Raman studies reveal that the Raman peaks at 340, 476, 625 and 776 cm(-1), are correspond to E-u, E-g, A(1g) and B-2g are respectively. Which are in good agreement with standard Raman vibrational modes and assign the pure and co-doped samples has tetragonal rutile phase structure. Optical absorption spectra show the absorption edge at 380 nm, in conformity with excitation and emission of PL spectra. The photoluminescence spectra (PL) exhibit the emission peaks in between 417 and 446 nm, which lie in UV and visible regions. SEM micro graphs show that the surface morphology of samples is nearly spherical, EDS spectra depicts the presence of Sn, O, Ni and Al in the chemical composition of samples in appropriate stoichiometric proportions. The transmission electron microscope micrographs show that the surface morphology of nanoparticles is spherical and average size of the nanoparticles is 20 nm. The magnetization measurements reveal that the anti ferromagnetism transferred to ferromagnetism in the prepared samples.