Open AccessThermoelectric properties of LaFeO3 system with doped Ti, Co, Cu
Author(s) -
Nguyễn Thị Thủy
Publication year - 2017
Publication title -
tạp chí khoa học đại học huế: khoa học tự nhiên/tạp chí khoa học đại học huế: khoa học tự nhiên (online)
Language(s) - English
Resource type - Journals
eISSN - 2615-9678
pISSN - 1859-1388
DOI - 10.26459/hueuni-jns.v126i1b.4155
Subject(s) - analytical chemistry (journal) , doping , materials science , sintering , scanning electron microscope , thermoelectric effect , electrical resistivity and conductivity , chemistry , nuclear chemistry , crystallography , metallurgy , physics , optoelectronics , chromatography , quantum mechanics , composite material , thermodynamics
LaFeO 3 system with doped Ti, Co, Cu was manufactured by solid state reaction method, it was sintered at 1250 0 C and 1290 0 C in 10 hours with a heating rate of 3 0 C/min. Using X-ray diffraction and Scanning Electron Microscope (SEM) to examine the structure, it reveals that samples are single-phase and orthogonal-perovskite structure describing by the Pnma space group, the unit cell volume of the samples increases when Ti, Co, Cu are doped to replace ion Fe +3 . The size of particle increase while raising the temperature of sintering. Measuring the resistance which depends on temperature between the room temperature and 1000K, it can be seen that when doping Co, Cu with the nominal component La(Fe 0,2 Co 0,2 Ti 0,6 )O 3 and La(Fe 0,4 Cu 0,1 Ti 0,5 )O 3 , the conductivity of samples increases respectively. Especially, the conductivity of Cu doped sample is higher than two other samples, and reach the highest conductivity at about 900 0 C, Seebeck coefficient S of La(Fe 0.6 Ti 0.4 )O 3 can be change from positive to negative at the temperature of around 700 0 C.