Structural, electrical, and dielectric properties of nickel-doped spinel LiMn O nanorods

Spinel pure and Ni-doped LiMn O nanorods were synthesized by a rapid microwave-assisted hydrothermal process followed by a solid-state reaction method. Their structural, morphological, electrical, and dielectric properties were investigated by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, transmission electron microscopy (TEM), and impedance spectroscopy techniques. Powder XRD studies revealed that all the synthesized samples have well-defined cubic crystal structure and the Ni doping in manganese sites did not affect spinel LiMn O structure. TEM images of pure and Ni-doped LiMn O samples clearly showed the formation of well-dispersed nanorods with uniform distribution. The Ni doping did not affect the nanorod morphology of pure LiMn O . The spinel LiMn O nanorods showed an electrical conductivity of 3.13 × 10  S cm , at room temperature. The A.C conductivity studies revealed that the pure and Ni-doped LiMn O nanorods obey Jonscher’s power law. The dielectric studies revealed that the dielectric constant of the samples decreases with frequency, which is due to decrease in charge accumulation at the interface.