Abstract
Nanosized tin oxide (SnO2) powders of different sizes were synthesized using co-precipitation method without using any surfactant or capping agent. The crystal structure, morphology, optical band gap and magnetic behavior of so formed SnO2 nanoparticles were investigated by using, x-ray diffraction (XRD), transmission electron microscopy (TEM), UV-visible absorption, and magnetic hysteresis loop measurements. Room temperature ferromagnetism with a significant blue shift in absorption edge was observed in 3pH grown sample. The controlled colloidal synthesis, with pH variation, and post annealing process grown larger sized nanoparticles have shown size dependent magnetic characteristics and sufficient red-shift in the absorption edge. The grain growth processes during colloidal synthesis and post annealing are also briefed. Keywords: SnO2, nanoparticles, ferromagnetism, diamagnetism, x-ray diffraction.