Open AccessThermoelectric Study of La2Ti2-xNbxO7 (0≤x≤0.25) Ceramic Materials
Author(s) -
Adindu C. Iyasara,
Felix U. Idu,
Emma Onochie Nwabineli,
Thaddeus. C. Azubuike,
C. V. Arinze
Publication year - 2020
Publication title -
journal of energy research and reviews
Language(s) - English
Resource type - Journals
ISSN - 2581-8368
DOI - 10.9734/jenrr/2020/v6i430179
Subject(s) - thermoelectric effect , materials science , microstructure , thermoelectric materials , seebeck coefficient , ceramic , doping , thermal conductivity , sintering , electrical resistivity and conductivity , thermoelectric generator , mineralogy , chemical engineering , analytical chemistry (journal) , metallurgy , composite material , optoelectronics , thermodynamics , chemistry , organic chemistry , physics , electrical engineering , engineering
La2Ti2-xNbxO7 (x = 0.00, 0.05, 0.10, 0.15, 0.20, 0.25) powders were synthesised via solid state reaction method, followed by sintering at 1673 K in a reducing atmosphere of 5% H2/N2 gas. The crystal structure, microstructure and thermoelectric (TE) properties of the pure and Nb-doped La2Ti2O7 ceramics were investigated. All compositions were single phase with porous microstructures consistent with their low experimental densities. Thermoelectric results of Nb-doped compositions showed improved properties in comparison to pure La2Ti2O7, suggesting that cation doping has the potential to improve the thermoelectric properties. Generally, the TE results obtained are not suitable for thermoelectric applications. However, the high Seebeck coefficient (≥190 μV/K) and glass-like thermal conductivity ( ≤2.26 w / m.k ) values achieved have opened a new window for exploring the thermoelectric potentials of La2Ti2O7 and other related oxides.