TY - JOUR
T1 - The effect of reduced graphene oxide on microstructure and thermoelectric properties of Nb-doped A-site-deficient SrTiO3 ceramics
AU - Wu, Cao
AU - Li, Jia
AU - Fan, Yuchi
AU - Xing, Juanjuan
AU - Gu, Hui
AU - Zhou, Zhenxing
AU - Lu, Xiaofang
AU - Zhang, Qihao
AU - Wang, Lianjun
AU - Jiang, Wan
N1 - Funding Information:
This work was funded by the Fundamental Research Funds for the Central Universities (2232017A-07), Natural Science Foundation of China (Nos.51432004, 51532006, 51774096, 51871053), Shanghai Committee of Science and Technology (No. 16JC1401800, 18JC1411200), DHU Distinguished Young Professor Program, Science and Technology Commission of Shanghai Municipality (16DZ2260601) and the 111 Project (D16002).
Funding Information:
This work was funded by the Fundamental Research Funds for the Central Universities ( 2232017A-07 ), Natural Science Foundation of China (Nos. 51432004 , 51532006 , 51774096 , 51871053 ), Shanghai Committee of Science and Technology (No. 16JC1401800 , 18JC1411200 ), DHU Distinguished Young Professor Program , Science and Technology Commission of Shanghai Municipality ( 16DZ2260601 ) and the 111 Project ( D16002 ).
Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2019/5/25
Y1 - 2019/5/25
N2 - As promising thermoelectric materials with great stability at high temperature, SrTiO3 based ceramics have attracted much attention, albeit the thermoelectric figure of merit remains relatively low for application. To improve the thermoelectric properties, reduced graphene oxide (RGO) is successfully incorporated into Nb-doped SrTiO3 (STNO) ceramics with Sr deficiency via a hetero-aggregation strategy followed by annealing and spark plasma sintering. The addition of RGO enhances the carrier concentration via reduction effect and increases the carrier mobility probably through lowering the double Schottky barrier at grain boundaries, resulting in highly improved electrical conductivity for the composites. Moreover, RGO also stimulates the separation of Nb rich TiO2 phase, which serves as a dispersion with low thermal conductivity to prohibit the phonon transport in the composites. Consequently, a ZT value reaching 0.22 at 800 K for the RGO/STNO nanocomposite is obtained, which is 1.8 times higher compared with the monolithic STNO.
AB - As promising thermoelectric materials with great stability at high temperature, SrTiO3 based ceramics have attracted much attention, albeit the thermoelectric figure of merit remains relatively low for application. To improve the thermoelectric properties, reduced graphene oxide (RGO) is successfully incorporated into Nb-doped SrTiO3 (STNO) ceramics with Sr deficiency via a hetero-aggregation strategy followed by annealing and spark plasma sintering. The addition of RGO enhances the carrier concentration via reduction effect and increases the carrier mobility probably through lowering the double Schottky barrier at grain boundaries, resulting in highly improved electrical conductivity for the composites. Moreover, RGO also stimulates the separation of Nb rich TiO2 phase, which serves as a dispersion with low thermal conductivity to prohibit the phonon transport in the composites. Consequently, a ZT value reaching 0.22 at 800 K for the RGO/STNO nanocomposite is obtained, which is 1.8 times higher compared with the monolithic STNO.
KW - Composites
KW - Graphene
KW - Perovskite
KW - Secondary phase
KW - Thermoelectric properties
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U2 - 10.1016/j.jallcom.2019.01.376
DO - 10.1016/j.jallcom.2019.01.376
M3 - Article
AN - SCOPUS:85061141423
SN - 0925-8388
VL - 786
SP - 884
EP - 893
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
ER -