Performance of a Thermoelectric Module Based on n-Type (La0.12Sr0.88)0.95TiO3−δ and p-Type Ca3Co4−xO9+δ.

Here, we present the performance of a thermoelectric (TE) module consisting of n-type (La_0.12Sr_0.88)_0.95TiO₃ and p-type Ca₃Co_4−xO_9+δ materials. The main challenge in this investigation was operating the TE module in different atmospheric conditions, since n-type has optimum TE performance at reducing conditions, while p-type has optimum at oxidizing conditions. The TE module was exposed to two different atmospheres and demonstrated higher stability in N₂ atmosphere than in air. The maximum electrical power output decreased after 40 h when the hot side was exposed to N₂ at 600°C, while only 1 h at 400°C in ambient air was enough to oxidize (La_0.12Sr_0.88)_0.95TiO₃ followed by a reduced electrical power output. The module generated maximum electrical power of 0.9 mW (∼ 4.7 mW/cm²) at 600°C hot side and δT ∼ 570 K in N₂, and 0.15 mW (∼ 0.8 mW/cm²) at 400°C hot side and δT ∼ 370 K in air. A stability limit of Ca₃Co_3.93O_9+δ at ∼ 700°C in N₂ was determined by in situ high-temperature x-ray diffraction. [ABSTRACT FROM AUTHOR]