Thermoelectric properties of Ca0.8Dy0.2MnO3 synthesized by solution combustion process

Abstract

High-quality Ca0.8Dy0.2MnO3 nano-powders were synthesized by the solution combustion process. The size of the synthesized Ca0.8Dy0.2MnO3 powders was approximately 23 nm. The green pellets were sintered at 1150-1300°C at a step size of 50°C. Sintered Ca0.8Dy0.2MnO3 bodies crystallized in the perovskite structure with an orthorhombic symmetry. The sintering temperature did not affect the Seebeck coefficient, but significantly affected the electrical conductivity. The electrical conductivity of Ca0.8Dy0.2MnO3 increased with increasing temperature, indicating a semiconducting behavior. The absolute value of the Seebeck coefficient gradually increased with an increase in temperature. The highest power factor (3.7 × 10-5 Wm-1 K-2 at 800°C) was obtained for Ca0.8Dy0.2MnO3 sintered at 1,250°C. In this study, we investigated the microstructure and thermoelectric properties of Ca0.8Dy0.2MnO3, depending on sintering temperature.

Crystal structure, energy transfer mechanism and tunable luminescence in Ce3+/Dy3+ co-activated Ca20Mg3Al26Si3O68 nanophosphors

“…The resulting final solution was heated slowly on a hot plate, boiled and dehydrated, thereby forming a highly viscous gel. Subsequently, the gel frothed and swelled with evolution of huge volume of gases [19]. The reaction lasted for 3-4 min and finally resulted as foam that readily crumbled into powder.…”

A Review on Electroactive Polymers for Waste Heat Recovery

“…Less toxic inorganic oxides are promising for the thermoelectric energy conversion from waste heat. A number of studies are devoted to this materials, see, e.g., [57,58,59,60,61,62]. Although the thermoelectric performance of oxide-based materials is not as good as tellurides and antimonides alloys, they have better stability and lower negative environmental impact [41].…”

“…However, they require sintering at 1000–1300 °C and are thermoelectrically active at high temperatures [41,57]. Thus, oxides may be suitable for high temperature applications.…”

Thermoelectric properties of n-type Ca1−xBixMn1−ySiyO3−δ (x=y=0.00, 0.02, 0.03, 0.04, and 0.05) system

“…Among these n-type materials, the perovskite CaMnO 3 -based compound has been intensively studied due to its relatively low electrical resistivity and large thermopower [6][7][8][9][10][11]. The decrease in the electrical resistivity by means of cationic substitution on the ''A'' site such as R 1Àx A x MnO 3 [8] (R: rare earth cation; A: divalent cation such as Ca, Sr, Ba, and Pb), La 1Àx Sr x MnO 3 [9], Ca 0.98 Gd 0.02 MnO 3Àd [10,11], Ca 1Àx Dy x MnO 2.89 [12], Ca 1Àx La x MnO 3 [13], or on the ''B'' site such as CaMn 1Àx Ru x O 3Àd [14,15], AMn 1Àx Mo x O 3 [15][16][17], Ca 1Àx Dy x Mn 1Ày Nb y O 3Àd [18], results from the adoption of a mixed-valance oxidation state of Mn 3+ /Mn 4+ which modifies the carrier concentration and mobility. Due to their low cost and promising thermoelectric properties, manganites were also investigated as potential candidates for n-type legs in thermoelectric modules [19,20].…”