title: Extraordinary Off-Stoichiometric Bismuth Telluride for Enhanced n-Type Thermoelectric Power Factor.
abstract: Thermoelectrics directly converts waste heat into electricity and is considered a promising means of sustainable energy generation. While most of the recent advances in the enhancement of the thermoelectric figure of merit (ZT) resulted from a decrease in lattice thermal conductivity by nanostructuring, there have been very few attempts to enhance electrical transport properties, i.e., the power factor. Here we use nanochemistry to stabilize bulk bismuth telluride (Bi2Te3) that violates phase equilibrium, namely, phase-pure n-type K0.06Bi2Te3.18. Incorporated potassium and tellurium in Bi2Te3far exceed their solubility limit, inducing simultaneous increase in the electrical conductivity and the Seebeck coefficient along with decrease in the thermal conductivity. Consequently, a high power factor of ∼43 μW cm-1K-2and a high ZT > 1.1 at 323 K are achieved. Our current synthetic method can be used to produce a new family of materials with novel physical and chemical characteristics for various applications.
authors.affiliation: Center for Nanoparticle Research, Institute for Basic Science (IBS) , Seoul 08826, Republic of Korea.
authors.forename: Kunsu
authors.initials: K
authors.lastname: Park
authors.forename: Kyunghan
authors.initials: K
authors.lastname: Ahn
authors.affiliation: Center for Nanoparticle Research, Institute for Basic Science (IBS) , Seoul 08826, Republic of Korea.
authors.forename: Joonil
authors.initials: J
authors.lastname: Cha
authors.affiliation: Center for Nanoparticle Research, Institute for Basic Science (IBS) , Seoul 08826, Republic of Korea.
authors.forename: Sanghwa
authors.initials: S
authors.lastname: Lee
authors.affiliation: Center for Nanoparticle Research, Institute for Basic Science (IBS) , Seoul 08826, Republic of Korea.
authors.forename: Sue In
authors.initials: SI
authors.lastname: Chae
authors.forename: Sung-Pyo
authors.initials: SP
authors.lastname: Cho
authors.affiliation: Department of Physics and KAIST Institute for the NanoCentury, Korea Advanced Institute of Science and Technology , Daejeon 34141, Republic of Korea.
authors.forename: Siheon
authors.initials: S
authors.lastname: Ryee
authors.affiliation: Thin Film Materials Research Center, Korea Research Institute of Chemical Technology , Daejeon 34114, Republic of Korea.
authors.forename: Jino
authors.initials: J
authors.lastname: Im
authors.affiliation: Creative Research Center, Creative and Fundamental Research Division, Korea Electrotechnology Research Institute (KERI) , Changwon 51543, Gyeongsangnam-do, Republic of Korea.
authors.forename: Jaeki
authors.initials: J
authors.lastname: Lee
authors.affiliation: Creative Research Center, Creative and Fundamental Research Division, Korea Electrotechnology Research Institute (KERI) , Changwon 51543, Gyeongsangnam-do, Republic of Korea.
authors.forename: Su-Dong
authors.initials: SD
authors.lastname: Park
authors.affiliation: Department of Physics and KAIST Institute for the NanoCentury, Korea Advanced Institute of Science and Technology , Daejeon 34141, Republic of Korea.
authors.forename: Myung Joon
authors.initials: MJ
authors.lastname: Han
authors.affiliation: Center for Nanoparticle Research, Institute for Basic Science (IBS) , Seoul 08826, Republic of Korea.
authors.forename: In
authors.initials: I
authors.lastname: Chung
authors.affiliation: Center for Nanoparticle Research, Institute for Basic Science (IBS) , Seoul 08826, Republic of Korea.
authors.forename: Taeghwan
authors.initials: T
authors.lastname: Hyeon