Opto, magnetic and electrochemical characterization of Ni_1−xCo_xO nanocrystals

This manuscript describes the synthesis and characterization of Ni_1−xCo_xO with x = 0.025, 0.05, 0.075 and 0.1 M. The structure and chemical compositions of the products were characterized by X-ray diffraction, energy dispersive spectrum and Fourier transform infrared spectroscopy. The obtained products were identified to be of face-centered-cubic structure. The optical properties of the products were studied by room temperature photoluminescence (PL) measurements. The PL spectra reveal a continuous suppression of both UV and green emissions by increasing the concentration of dopant ion. The suppressed green emission indicates the quenching of surface defects present in the nanostructures. The morphology of the doped product was analyzed by the scanning electron microscope and confirmed by field emission transmission electron microscope. Magnetic measurements show an enhancement in ferromagnetism at higher concentration of cobalt doping. The electrochemical characterization showed that the NiO doped with 0.05 M of cobalt exhibited much improved specific capacitance than that of pure NiO.