resumo
This work seeks possibilities for advancing the thermoelectric oxide technology by exploring a module design involving materials produced by laser processing. A tubular thermoelectric generator of modular construction with functional elements located parallel to a pipe-shaped heat source was designed and manufactured. The p- and n-type counterparts based on Ca3Co4O9 and Ca0.95Pr0.05MnO3 were grown by the laser floating zone (LFZ) technique, ensuring highly dense microstructures and giving the unique possibility for fast and crucible-free processing of the legs with desirable geometry. The detailed structural and microstructural characterization indicated that the LFZ processing should be accompanied with an additional thermal annealing step to equilibrate the phase composition. Although the measured electrical performance was found close to or slightly higher compared to that of similar materials produced by other routes, it was still notably suppressed by the remaining phase impurities affecting the module's output. The maximum observed power output of the module containing 12 Ca3Co4O9/Ca0.95Pr0.05MnO3 thermoelectric couples reached up to 20 mW at a temperature gradient of 389 degrees C and a hot side temperature of 525 degrees C. The contribution of various factors to the overall performance was analyzed. The results suggest that the power output could be significantly enhanced by decreasing the contact resistance at the cold side and proper optimization of the LFZ processing conditions.
palavras-chave
POWER-GENERATION; FABRICATION; CHALLENGES; CERAMICS; PROGRESS
categoria
Chemistry, Physical; Energy & Fuels; Materials Science, Multidisciplinary
autores
Merkulov, OV; Lopes, D; Markov, AA; Ferreira, NM; Patrakeev, MV; Kovalevsky, AV
nossos autores
Andrei Kavaleuski
Investigador principal
Nuno Miguel Freitas Ferreira
Bolseiro de pós-Doutoramentoagradecimentos
O.V. Merkulov acknowledges the support of the grant MK4182.2021.1.3 of the President of the Russian Federation for the young scientists. The work was carried out in accordance with the state assignment for the Institute of Solid State Chemistry of the Ural Branch of the Russian Academy of Sciences (theme No. AAAA-A19-119031890026-6). This work was also supported by the project REMOTE (POCI-01-0145FEDER-031875), CICECO-Aveiro Institute of Materials (ref. UIDB/50011/2020 & UIDP/50011/2020), and project i3N (UIDB/50025/2020 & UIDP/50025/2020), financed by COMPETE 2020 Program and National Funds through the FCT/MEC and when applicable co-financed by FEDER under the PT2020 Partnership Agreement. N. M. Ferreira also acknowledges the support of national funds (OE), through FCT -Fundac ncia e a Tecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5, and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. D. Lopes acknowledges the support of the FCT grant 2020.06454.BD.