Cairo University

MTPR Journal

 

CHARACTERIZATION of LA0.7SR0.3MNO3 THIN FILMS by PULSED LASER DEPOSITION for SOFC APPLICATION

2016-12-17
A.A. El-Aziem*a, Y. Badra, K.M. El-Khatibb, M. A. Hafez a
a Department of Laser Sciences and Interaction, National Institute of Laser Enhanced Sciences (NILES), Cairo University
b chemical Engineering & Pilot Plant Department, Engineering Division, National Research Center, Dokki, Giza, Egypt

Vol./Issue: 16 , id: 194

La0.7Sr0.3MnO3 (LSM) polycrystalline was synthesized using sol gel method at 600 ᵒC. The structure and elemental analysis were confirmed by XRD and EDX respectively with rhombohedral crystal structure. HR-TEM imaging showed that the prepared LSM has uniform shape with agglomeration and average size from 100- 200 nm by PSD. Thin films of LSM with 97 nm were deposited on clean Si (100) single crystal substrate by PLD using Nd: YAG (1064 nm) with 10 Hz repetition rate and 6 ns pulse duration at room temperature in high vacuum of ~ 6´10-6 Torr. LSM films were annealed at temperatures of 400, 600, 800 and 1000 ᵒC for 2h. The XRD indicated that crystallization is enhanced by increasing annealing temperature. Additionally, grain size was increased by rising annealing temperature as indicated from FESEM imaging. The average roughness (Ra) and root mean square roughness (Rq) were decreased by increasing annealing temperature up to 600 ᵒC then increased by further temperature increasing as showed by AFM images. Raman spectra were recorded in wave numbers 100-100 ٠cm-1 and all major peaks appeared at annealing temperature 1000 ᵒC. The electrical and dielectric properties for the as deposited film and films annealed at different temperatures also recorded in temperature ranges from room temperature to 200 °C and found to be sensitive to temperature and open possibility for using LSM as cathode part in solid oxide fuel cell (SOFC).