title: Dielectric Mismatch Mediates Carrier Mobility in Organic-Intercalated Layered TiS2.
abstract: The dielectric constant is a key parameter that determines both optical and electronic properties of materials. It is desirable to tune electronic properties though dielectric engineering approach. Here, we present a systematic approach to tune carrier mobilities of hybrid inorganic/organic materials where layered two-dimensional transition-metal dichalcogenide TiS2 is electrochemically intercalated with polar organic molecules. By manipulating the dielectric mismatch using polar organic molecules with different dielectric constants, ranging from 10 to 41, the electron mobility of the TiS2 layers was changed three times due to the dielectric screening of the Coulomb-impurity scattering processes. Both the overall thermal conductivity and the lattice thermal conductivity were also found to decrease with an increasing dielectric mismatch. The enhanced electrical mobility along with the decreased thermal conductivity together gave rise to a significantly improved thermoelectric figure of merit of the hybrid inorganic/organic materials at room temperature, which might find applications in wearable electronics.
authors: State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University , Beijing 100084, China.|Graduate School of Engineering, Nagoya University , Nagoya 464-8603, Japan.
authors: Chunlei
authors: C
authors: Wan
authors: Graduate School of Engineering, Nagoya University , Nagoya 464-8603, Japan.
authors: Yumi
authors: Y
authors: Kodama
authors: Graduate School of Engineering, Nagoya University , Nagoya 464-8603, Japan.
authors: Mami
authors: M
authors: Kondo
authors: Interdisciplinary Graduate School of Science and Engineering, Shimane University , 1060 Nishikawatsu-cho, Matsue 690-8504, Japan.
authors: Ryo
authors: R
authors: Sasai
authors: Department of Mechanical Engineering, University of Colorado , Boulder, Colorado 80309, United States.
authors: Xin
authors: X
authors: Qian
authors: Department of Mechanical Engineering, University of Colorado , Boulder, Colorado 80309, United States.
authors: Xiaokun
authors: X
authors: Gu
authors: KOBELCO Research Institute , Kobe, Hyogo 651-2271, Japan.
authors: Kenji
authors: K
authors: Koga
authors: KOBELCO Research Institute , Kobe, Hyogo 651-2271, Japan.
authors: Kazuhisa
authors: K
authors: Yabuki
authors: Department of Mechanical Engineering, University of Colorado , Boulder, Colorado 80309, United States.
authors: Ronggui
authors: R
authors: Yang
authors: Graduate School of Engineering, Nagoya University , Nagoya 464-8603, Japan.
authors: Kunihito
authors: K
authors: Koumoto
keywords: Titanium disulfide; dielectric mismatch; hybrid materials; thermoelectrics; transition-metal dichalcogenide