resumo
Co -substitution of Eu and Nb into insulating CaTiO3 can make it a good n -type potential thermoelectric (TE) material. In the present work, solid solution compounds with the nominal composition Ca0.8Eu0.2Ti1-xNbxO3-delta (x = 0.05, 0.08, 0.1, 0.12) were synthesized and sintered in different atmospheres, including argon (Ar) and forming gas (5 vol% H2 in Ar). Notably, the different reduction effects of these atmospheres resulted in significant differences in phase formation, grain size, oxygen deficiency, and TE properties of the synthesized samples. Introducing additional electrons to the system by donor substitution of Ti with Nb leads to significant changes in the electrical conductivity and Seebeck coefficient. The most favorable TE performance of the prepared samples was found in the sample with x = 0.05, primarily attributed to its proper charge carrier concentration. This work highlights the crucial role of the sintering atmosphere in manipulating the TE performance of n -type CaTiO3-based ceramics, an effect similar to donor doping.
palavras-chave
TRANSPORT-PROPERTIES; TUNGSTEN CARBIDE; OXIDE MATERIALS; GRAIN-GROWTH; PERFORMANCE; SRTIO3; GENERATORS; STATE
categoria
Chemistry; Physics
autores
Xiao, XX; Widenmeyer, M; Xie, WJ; Ding, JX; Thiem, M; Li, W; Kovalevsky, A; Weidenkaff, A
nossos autores
Andrei Kavaleuski
Investigador principalProjectos
Collaboratory for Emerging Technologies, CoLab (EMERGING TECHNOLOGIES)
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
agradecimentos
This research was partially supported by DAAD Forderprogramme (Project -ID: 57610929) and Seed -funding of TUDa (project -ID: 40101580). The financial support of the German Science Foundation (DFG) in the Collaborative Research Centre 1548 (CRC 1548, project number 463184206) is acknowledged. A.K. acknowledges the support of the project CICECO - Aveiro Institute of Materials (UIDB/50011/2020 (DOI 10.54499/UIDB/50011/2020) , UIDP/50011/2020 (DOI 10.54499/UIDP/50011/2020) & LA/P/0006/2020 (DOI 10.54499/LA/P/0006/2020) ) financed by national funds through the FCT/MCTES (PIDDAC) .r (DOI 10.54499/UIDB/50011/2020) , UIDP/50011/2020 (DOI 10.54499/UIDP/50011/2020) & LA/P/0006/2020 (DOI 10.54499/LA/P/0006/2020) ) financed by national funds through the FCT/MCTES (PIDDAC) .