Synthesis, magnetic and dielectric characterization of nanocrystalline solid solutions of In2−xNixO3 (x = 0.05, 0.10 and 0.15)

• Monophasic Ni-doped In2O3 nanoparticles by solvothermal method for first time.
• Plausible reaction mechanism using thermogravimetric analysis.
• High surface area with small particle size obtained.
• Solid solutions exhibit paramagnetism with very weak antiferromagnetic interactions.

In2−xNixO3 (x = 0.05, 0.10 and 0.15) nanoparticles were successfully synthesized by solvothermal method by the thermal decomposition of oxalate precursor at 450 °C for the first time. X-ray diffraction studies showed the formation of highly crystalline and monophasic cubic structure of In2O3 which is attributed to the formation of solid solution. These nanoparticles show good optical transmittance in the visible region. Optical measurements showed an energy band gap which decreases with increasing Ni concentration. The grain size decreases from 15 nm to 8 nm and surface area increases from 90 to 254 m2 g−1 on increasing the Ni concentration. High dielectric constant and dielectric loss has been obtained which indicates the conducting nature of these solid solutions. Magnetic measurements showed that the samples are strong paramagnetic in nature with very weak antiferromagnetic interactions. No evidence of ferromagnetism is observed for these solid solutions at room temperature.

Monophasic and crystalline In2−xNixO3 nanoparticles of size 8–15 nm have been synthesized solvothermally and showed red shift in energy band gap which decreases on increasing Ni2+ concentration in In2O3 host lattice.Figure optionsDownload as PowerPoint slide