Effect of indium-doping on the structural and dielectric properties of gallium ferrite nanoparticles
Yi-Hua Shih1*, Jin-Te Wang1, Chun-Chien Tseng1, Yu-Wei Lue1, Yu-Ru Wang1, Yi-Ru Yang1, Tai-Chun Han1
1Department of Applied Physics, National University of Kaohsiung, Kaohsiung, Taiwan
* Presenter:Yi-Hua Shih, email:a1084356@mail.nuk.edu.tw
In this study, we prepared a series of Ga1-xInxFeO3 (GIFO, 0 ≦ x ≦ 0.15) nanoparticles by sol-gel method. Impact of indium (In) on structural and dielectric properties of gallium ferrite nanoparticles has been investigated. All GIFO samples crystallize in the orthorhombic structure with Pc21n space group, as confirmed by X-ray diffraction and Raman spectroscopy. In addition, the average crystallite size (D) and lattice strain (k) of GIFO was estimated by using Debye-Scherrer formula and Williamson-Hall (W-H) method. It has shown also by increasing In-content, the average crystallite size decrease, while the lattice strain increases. The dielectric spectrum of the GIFO samples was obtained, the strong frequency-dependent dielectric constant, considerably high value at low frequency and low value at high frequency, may be due to the Maxwell-Wagner polarization effect. Interestingly, the dielectric characterization also indicates that the sample of Ga0.95In0.05FeO3 exhibits the largest dielectric constant at low frequency. Furthermore, it was found that In-doping in GaFeO3allows decreasing the leakage current density. This can be attributed to the variation of Fe3+distribution difference between the tetrahedral and octahedral sites after indium-doping.

Keywords: nanoparticle, gallium ferrite, structure, dielectric constant