Growth of Co-Doped ZnO Ferromagnetic Nanoparticles by Sol-Gel Method

Co-doped ZnO nanoparticles have been synthesized by a simple sol-gel route using zinc acetate dihydrate and cobalt(II) acetate tetrahydrate as precursors. The X- ray diffraction and high-resolution transmission electron microscopy show that Co doping has a significant effect on the crystalline nature of ZnO nanoparticles. Thermal analysis indicates that the Co-doped ZnO system is well stable above 300 ∘C. Raman spectroscopy shows the prominent modes at 331, 434, and 579 cm−1 with 0–2 % doping, whereas additional modes at 490, 525, and 715 cm−1 corresponding to secondary phases have also been observed for 3–5 % of Co doping in ZnO nanoparticles. The M–H and M–T curves confirmed the ferromagnetic nature of Co-doped ZnO nanoparticles at room temperature.