Copper chalcogenides are outstanding thermoelectric materials for applications in the medium-high temperature range. Among different chalcogenides, while Cu2−xSe is characterized by higher thermoelectric figures of merit, Cu2−xS provides advantages in terms of low cost and element abundance. In the present work, we investigate the effect of different dopants to enhance the Cu2−xS performance and also its thermal stability. Among the tested options, Pb-doped Cu2−xS shows the highest improvement in stability against sulfur volatilization. Additionally, Pb incorporation allows tuning charge carrier concentration, which enables a significant improvement of the power factor. We demonstrate here that the introduction of an optimal additive amount of just 0.3% results in a threefold increase of the power factor in the middle-temperature range (500–800 K) and a record dimensionless thermoelectric figure of merit above 2 at 880 K.
This work was supported by the European Regional Development Fund and by the Spanish Ministerio de Economía y Competitividad through the project SEHTOP (ENE2016-77798-C4-3-R). MI acknowledges financial support from IST Austria. YL acknowledges funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 754411. YZ, CX, XW, KX and TZ thank the China Scholarship Council for the scholarship support. ICN2 acknowledges funding from Generalitat de Catalunya 2017 SGR 327 and the Spanish MINECO project ENE2017-85087-C3. ICN2 is supported by the Severo Ochoa program from the Spanish MINECO (grant no. SEV-2017-0706) and is funded by the CERCA program/Generalitat de Catalunya. Part of the present work has been performed in the framework of Universitat Autònoma de Barcelona Materials Science Ph.D. program. M.C.S. has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 754510 (PROBIST) and the Severo Ochoa programme. P.G. acknowledges financial support from the Spanish government (MICIU) through the RTI2018-102006-J-I00 project and the Catalan Agency of Competitiveness (ACCIO) through the TecnioSpring+ Marie Sklodowska-Curie action TECSPR16-1-0082. YZ and CX contributed equally to this work.
Zhang Y, Xing C, Liu Y, et al. Doping-mediated stabilization of copper vacancies to promote thermoelectric properties of Cu2-xS. Nano Energy. 2021;85(7). doi:10.1016/j.nanoen.2021.105991
Zhang, Y., Xing, C., Liu, Y., Spadaro, M. C., Wang, X., Li, M., … Cabot, A. (2021). Doping-mediated stabilization of copper vacancies to promote thermoelectric properties of Cu2-xS. Nano Energy. Elsevier. https://doi.org/10.1016/j.nanoen.2021.105991
Zhang, Yu, Congcong Xing, Yu Liu, Maria Chiara Spadaro, Xiang Wang, Mengyao Li, Ke Xiao, et al. “Doping-Mediated Stabilization of Copper Vacancies to Promote Thermoelectric Properties of Cu2-XS.” Nano Energy. Elsevier, 2021. https://doi.org/10.1016/j.nanoen.2021.105991.
Y. Zhang et al., “Doping-mediated stabilization of copper vacancies to promote thermoelectric properties of Cu2-xS,” Nano Energy, vol. 85, no. 7. Elsevier, 2021.
Zhang Y, Xing C, Liu Y, Spadaro MC, Wang X, Li M, Xiao K, Zhang T, Guardia P, Lim KH, Moghaddam AO, Llorca J, Arbiol J, Ibáñez M, Cabot A. 2021. Doping-mediated stabilization of copper vacancies to promote thermoelectric properties of Cu2-xS. Nano Energy. 85(7), 105991.
Zhang, Yu, et al. “Doping-Mediated Stabilization of Copper Vacancies to Promote Thermoelectric Properties of Cu2-XS.” Nano Energy, vol. 85, no. 7, 105991, Elsevier, 2021, doi:10.1016/j.nanoen.2021.105991.