Dielectric behavior and phase transition of La2Mo2O9 films synthesized by spray pyrolysis technique

• Published in: Journal of materials science. Materials in electronics 2023-02, Vol.34 (5), Article 387
• Main Authors: Kadam, Govinda A., Patil, Sagar A., Patil, Bajarang B., Kumbhar, Sarita S., Kumbhar, Sambhaji S., Madake, Suraj B., Kadam, Laxman D., Ma, Yuan-Ron, Kadam, Sujit A., Nimat, Rajesh K.
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Materials Science; Optical and Electronic Materials
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-022-09796-0

The novel fast oxide ion-conducting material La 2 Mo 2 O 9 (LAMOX) thin films were synthesized by using the cost-effective chemical spray pyrolysis technique. Thermal Gravimetric and differential thermal analysis show the phase transition of La 2 Mo 2 O 9 from α-monoclinic to β-cubic phase at 546.5 °C. Rietveld refinement confirms the stabilization of the β-cubic phase for La 2 Mo 2 O 9 thin films at high temperature. The porous morphology was observed after the annealing and the XPS study revealed elements La, Mo and O observed on the surface of thin films. The temperature and frequency-dependent dielectric constant were studied using an LCR-Q meter in the frequency range of 20 Hz–300 kHz. As the frequency increases, the dielectric constant and dielectric loss decreases for all La 2 Mo 2 O 9 thin films. The dielectric constant, dielectric loss and AC conductivity varied with increasing temperature, shows two relaxation peaks indicating the presence of oxide ion vacancies for ion conduction. The complex impedance shows the Cole–Cole plot for the LAMOX thin films.