title: Synthesis of Multishell Nanoplates by Consecutive Epitaxial Growth of Bi2Se3 and Bi2Te3 Nanoplates and Enhanced Thermoelectric Properties.
abstract: We herein demonstrate the successive epitaxial growth of Bi2Te3 and Bi2Se3 on seed nanoplates for the scalable synthesis of heterostructured nanoplates (Bi2Se3@Bi2Te3) and multishell nanoplates (Bi2Se3@Bi2Te3@Bi2Se3, Bi2Se3@Bi2Te3@Bi2Se3@Bi2Te3). The relative dimensions of the constituting layers are controllable via the molar ratios of the precursors added to the seed nanoplate solution. Reduction of the precursors produces nanoparticles that attach preferentially to the sides of the seed nanoplates. Once attached, the nanoparticles reorganize epitaxially on the seed crystal lattices to form single-crystalline core-shell nanoplates. The nanoplates, initially 100 nm wide, grew laterally to 620 nm in the multishell structure, while their thickness increased more moderately, from 5 to 20 nm. The nanoplates were pelletized into bulk samples by spark plasma sintering and their thermoelectric properties are compared. A peak thermoelectric figure of merit (ZT) ∼0.71 was obtained at 450 K for the bulk of Bi2Se3@Bi2Te3 nanoplates by simultaneous modulation of electronic and thermal transport in the presence of highly dense grain and phase boundaries.
authors.affiliation: †Department of Materials Science and Engineering, Yonsei University, 134 Shinchon-dong, Seoul 120-749, Korea.
authors.forename: Yuho
authors.initials: Y
authors.lastname: Min
authors.affiliation: ‡Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang 790-784, Korea.
authors.forename: Gyeongbae
authors.initials: G
authors.lastname: Park
authors.affiliation: †Department of Materials Science and Engineering, Yonsei University, 134 Shinchon-dong, Seoul 120-749, Korea.
authors.forename: Bongsoo
authors.initials: B
authors.lastname: Kim
authors.affiliation: ‡Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang 790-784, Korea.
authors.forename: Anupam
authors.initials: A
authors.lastname: Giri
authors.forename: Jie
authors.initials: J
authors.lastname: Zeng
authors.affiliation: ∥Materials Research Center, Samsung Advanced Institute of Technology, Samsung Electronics, Suwon 443-803, Korea.
authors.forename: Jong Wook
authors.initials: JW
authors.lastname: Roh
authors.affiliation: ∥Materials Research Center, Samsung Advanced Institute of Technology, Samsung Electronics, Suwon 443-803, Korea.
authors.forename: Sang Il
authors.initials: SI
authors.lastname: Kim
authors.affiliation: ⊥Department of Nano Applied Engineering, Kangwon National University, Chuncheon 200-701, Korea.
authors.forename: Kyu Hyoung
authors.initials: KH
authors.lastname: Lee
authors.affiliation: ‡Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang 790-784, Korea.
authors.forename: Unyong
authors.initials: U
authors.lastname: Jeong
keywords: Bi2Se3; Bi2Te3; core−shell nanoplates; multishell nanoplates; seeded growth; thermoelectric properties; two-dimensional materials