New La1-xTbxMnO3 nanoparticles: fabrication via wet chemical route for enhanced structural, electrical and dielectric parameters

作者：Warsi Muhammad Farooq; Tayyab Hafiz Muhammad Waqar; Agboola Philips Olaleye; Ahmad Sajjad; Khan Muhammad Azhar; Shakir Imran

来源：Materials Research Express, 2018, 5(1): 015055.

DOI：10.1088/2053-1591/aaa689

• perovskites
• rare earth
• nanoparticles
• dielectric

Rare earth Tb3+ doped LaMnO3 nanoparticles were fabricated via cheap facile wet chemical micro emulsion route. X-ray diffraction and spectral analysis by Fourier transform infrared radiation spectroscopy confirmed the formation of orthorhombic structure of La1-xTbxMnO3 nanoparticles. The crystallite size was found in the range 10-50 nm. The lattice parameters (a)-(c) and cell volume were decreased as the La3+ was replaced with Tb3+. This was attributed to the smaller ionic radius of Tb3+ (0.92 angstrom) as compared to that of La3+ (1.03 angstrom). Scanning electron microscopic images showed that the La1-xTbxMnO3 grains are well structured and have no cracks. They are non-homogeneous in size with occasionally aggregation. The dielectric measurements of La1-xTbxMnO3 nanoparticles performed in the frequency range 1 x 10(6) to 3 x 10(9) Hz showed that both Tb3+ contents and frequency decreased the dielectric parameters. At high frequency, the dipoles could not follow the alternating field and thus resulted in decreased dielectric parameters. The Tb3+ in LaMnO3 decreased the internal viscosity of the system that affected the dielectric parameters. DC-electrical resistivity was enhanced with the increased Tb3+ contents. This might be due to f-d orbital coupling between rare earth and transition metal cations in La1-xTbxMnO3 nanoparticles.

• 出版日期2018-1