2019/11/15 by Arzena Khatun, Shamim Sk, Khatun, Arzena +7
Materials Science · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Advanced Thermoelectric Materials and Devices #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Physics of Superconductivity and Magnetism #Strongly Correlated Electrons (cond-mat.str-el) #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.48550/arxiv.1911.06584
arxiv created 2019/11/15 · openalex publication_date 2019/11/15 · arxiv updated 2019/11/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report the thermoelectric (TE) properties of Na0.74Co0.95Nb0.05O2 in the temperature range 300-1200 K, as a potential candidate for p-type thermoelectric material. The experimental values of Seebeck coefficient (S) are ∼ 82-121 μV/K measured in the temperature range 300-620 K. The positive values of S in the entire temperature range indicates p-type behaviour of the compound. At 300 K the experimental value of thermal conductivity ( κ) is ∼ 1.88 W/m-K that increases up to ∼ 420 K, then decreases till 620 K with corresponding value ∼ 1.86 W/m-K. To understand the experimentally observed transport properties, we have calculated S and ρ of this compound. Then, based on theoretical understanding, we have estimated figure-of-merit (ZT) up to 1200 K by using calculated S and ρ values with extrapolated experimental κ. The value of ZT is found to be ∼ 0.03 at 300 K, whereas, the highest value is observed as ∼ 1.7 at 1200 K. Finally, we have calculated the efficiency (η) by keeping the cold end temperature (Tc) fixed at 500 K and varying hot end temperature (Th) from 500 to 1200 K, respectively. The maximum value of η is found to be ∼ 8 %, when Tc and Th are fixed at 500 and 1200 K, respectively. This result suggests that Na0.74Co0.95Nb0.05O2 compound can be used as a p-leg for making high temperature TE generator (TEG).