Abstract
The fine control of antisite defects for Bi2Te3-based materials is necessary to improve their thermoelectric performance using the optimization of a carrier concentration. In this work, we attempted to tune the n-type carrier concentration by forming antisite TeBi defects under a Te-rich condition for Cu0.01Bi2Te2.3+xSe0.7 samples (0 ≤ x ≤ 0.7). The electrical resistivity decreases with increasing the amount of excess Te in the sample of Cu0.01Bi2Te2.3+xSe0.7, which is originated from the increase in the electron carrier concentration for the Te-excess samples. The highest power factor of 2.72 mW/m K2 is obtained at 323 K for Cu0.01Bi2Te2.4Se0.7, which is enhanced by ~ 20% compared to the x = 0 sample. The highest ZT of 0.92 is achieved at 473 K for Cu0.01Bi2Te2.4Se0.7, which is 11% higher than that of x = 0 sample (ZT = 0.83). We demonstrate that the optimization of n-type carrier concentration by forming antisite TeBi defects in n-type Bi2Te3-based materials should be effective for enhancing their thermoelectric performance.
Graphical Abstract
![](http://media.springernature.com/lw685/springer-static/image/art%3A10.1007%2Fs13391-018-0021-6/MediaObjects/13391_2018_21_Figa_HTML.gif)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs13391-018-0021-6/MediaObjects/13391_2018_21_Fig1_HTML.gif)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs13391-018-0021-6/MediaObjects/13391_2018_21_Fig2_HTML.jpg)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs13391-018-0021-6/MediaObjects/13391_2018_21_Fig3_HTML.gif)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs13391-018-0021-6/MediaObjects/13391_2018_21_Fig4_HTML.gif)
Similar content being viewed by others
References
Poudel, B., Hao, Q., Ma, Y., Lan, Y., Minnich, A., Yu, B., Yan, X., Wang, D., Muto, A., Vashaee, D., Chen, X., Liu, J., Dresselhaus, M.S., Chen, G., Ren, Z.: High-thermoelectric performance of nanostructured Bismuth antimony telluride bulk alloys. Science 320, 634 (2008)
Liu, C.-J., Lai, H.-C., Liu, Y.-L., Chen, L.-R.: High thermoelectric figure-of-merit in p-type nanostructured (Bi, Sb)2Te3 fabricated via hydrothermal synthesis and evacuated-and-encapsulated sintering. J. Mater. Chem. 22, 4825 (2012)
Kim, S.I., Lee, K.H., Mun, H.A., Kim, H.S., Hwang, S.W., Roh, J.W., Yang, D.J., Shin, W.H., Li, X.S., Lee, Y.H., Snyder, G.J., Kim, S.W.: Dense dislocation arrays embedded in grain boundaries for high-performance bulk thermoelectrics. Science 348, 109 (2015)
Zhang, Y., Day, T., Snedaker, M.L., Wang, H., Krämer, S., Birkel, C.S., Ji, X., Liu, D., Snyder, G.J., Stucky, G.D.: A mesoporous anisotropic n-type Bi2Te3 monolith with low thermal conductivity as an efficient thermoelectric material. Adv. Mater. 24, 5065 (2012)
Hu, L., Zhu, T., Liu, X., Zhao, X.: Point defect engineering of high-performance bismuth-telluride-based thermoelectric materials. Adv. Func. Mater. 24, 5211 (2014)
Liu, W.-S., Zhang, Q., Lan, Y., Chen, S., Yan, X., Zhang, Q., Wang, H., Wang, D., Chen, G., Ren, Z.: Thermoelectric property studies on Cu-doped n-type CuxBi2Te2.7Se0.3 nanocomposite. Adv. Energy Mater. 1, 577 (2011)
Lin, C.-C., Ginting, D., Lydia, R., Lee, M.H., Rhyee, J.-S.: Thermoelectric properties and extremely low lattice thermal conductivity in p-type Bismuth Tellurides by Pb-do** and PbTe precipitation. J. Alloys Comp. 671, 538 (2016)
Wang, S., Sun, Y., Yang, J., Duan, B., Wu, L., Zhang, W., Yang, J.: High thermoelectric performance in Te-free (Bi, Sb)2Se3 via structural transition induced band convergence and chemical bond softening. Energy Environ. Sci. 9, 3436 (2016)
Wang, S., Li, H., Lu, R., Zheng, G., Tang, X.: Metal nanoparticle decorated n-type Bi2Te3-based materials with enhanced thermoelectric performances. Nanotechnology 24, 285702 (2013)
Cuia, J.L., Maob, L.D., Yang, W., Xu, X.B., Chen, D.Y., **u, W.J.: Thermoelectric properties of Cu-doped n-type (Bi2Te3)0.9–(Bi2-xCuxSe3)0.1(x = 0–0.2) alloys. J. Solid State Chem. 180, 3583 (2007)
Han, M.-K., Ahn, K., Kim, H.J., Rhyee, J.-S., Kim, S.-J.: Formation of Cu nanoparticles in layered Bi2Te3 and their effect on ZT enhancement. J. Mater. Chem. 21, 11365 (2011)
Zhang, J.-M., Ming, W., Huang, Z., Liu, G.-B., Kou, X., Fan, Y., Wang, K.L., Yao, Y.: Stability, electronic, and magnetic properties of the magnetically doped topological insulators Bi2Se3, Bi2Te3, and Sb2Te3. Phys. Rev. B 88, 235131 (2013)
Cho, Sunglae, Kim, Yunki, DiVenere, Antonio, Wong, George K., Ketterson, John B., Meyer, Jerry R.: Antisite defects of Bi2Te3 thin films. Appl. Phys. Lett. 75, 1401 (1999)
Oh, M.W., Son, J.H., Kim, B.S., Park, S.D., Min, B.K., Lee, H.W.: Antisite defects in n-type Bi2(Te, Se)3: experimental and theoretical studies. J. Appl. Phys. 115, 133706 (2014)
Snyder, G.J., Toberer, E.S.: Complex thermoelectric materials. Nat. Mater. 7, 105–114 (2008)
Hashibon, Adham, Elaasser, Christian: First-principles density functional theory study of native point defects in Bi2Te3. Phys. Rev. B 84, 144117 (2011)
West, D., Sun, Y.Y., Wang, H., Bang, J., Zhang, S.B.: Native defects in second-generation topological insulators: effect of spin-orbit interaction on Bi2Se3. Phys. Rev. B 86, 121201 (2012)
Ginting, D., Lin, C.-C., Lydia, R., So, H.S., Lee, H., Hwang, J., Kim, W., Orabi, R.A.R.A., Rhyee, J.-S.: High thermoelectric performance in pseudo quaternary compounds of (PbTe)0.95−x(PbSe)x(PbS)0.05 by simultaneous band convergence and nano precipitation. Acta Mater. 131, 98 (2017)
Orabi, R.A.R.A., Hwang, J., Lin, C.-C., Gautier, R., Fontaine, B., Kim, W., Rhyee, J.-S., Wee, D., Fornari, M.: Band degeneracy, low thermal conductivity, and high thermoelectric figure of merit in SnTe–CaTe alloys. Chem. Mater. 29, 612 (2016)
Zhang, Y.: First-principles Debye–Callaway approach to lattice thermal conductivity. J. Materiomics 2, 237 (2016)
Acknowledgements
This research was supported by Nano Material Technology Development Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2011-0030147) and by the Materials and Components Technology Development Program of MOTIE/KEIT (10063286).
Author information
Authors and Affiliations
Corresponding authors
Rights and permissions
About this article
Cite this article
Back, S.Y., Cho, H., Kim, J.H. et al. Enhancement of Thermoelectric Properties in n-Type Cu0.01Bi2Te2.3+xSe0.7 (0 ≤ x ≤ 0.7) Compounds with Te-Excess. Electron. Mater. Lett. 14, 139–145 (2018). https://doi.org/10.1007/s13391-018-0021-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s13391-018-0021-6