Flexible n-type thermoelectric materials by organic intercalation of layered transition metal dichalcogenide TiS 2

Chunlei Wan*, Xiaokun Gu, Feng Dang, Tomohiro Itoh, Yifeng Wang, Hitoshi Sasaki, Mami Kondo, Kenji Koga, Kazuhisa Yabuki, G. Jeffrey Snyder, Ronggui Yang, Kunihito Koumoto

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

406 Scopus citations

Abstract

Organic semiconductors are attracting increasing interest as flexible thermoelectric materials owing to material abundance, easy processing and low thermal conductivity. Although progress in p-type polymers and composites has been reported, their n-type counterpart has fallen behind owing to dificulties in n-type doping of organic semiconductors. Here, we present an approach to synthesize n-type flexible thermoelectric materials through a facile electrochemical intercalation method, fabricating a hybrid superlattice of alternating inorganic TiS2 monolayers and organic cations. Electrons were externally injected into the inorganic layers and then stabilized by organic cations, providing n-type carriers for current and energy transport. An electrical conductivity of 790 S cm-1 and a power factor of 0.45mWm-1 K-2 were obtained for a hybrid superlattice of TiS2/[(hexylammonium)x(H2O)y(DMSO)z], with an in-plane lattice thermal conductivity of 0.12±0.03Wm-1 K-1, which is two orders of magnitude smaller than the thermal conductivities of the single-layer and bulk TiS2. High power factor and low thermal conductivity contributed to a thermoelectric figure of merit, ZT, of 0.28 at 373 K, which might find application in wearable electronics.

Original languageEnglish (US)
Pages (from-to)622-627
Number of pages6
JournalNature materials
Volume14
Issue number6
DOIs
StatePublished - Jun 26 2015

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Fingerprint Dive into the research topics of 'Flexible n-type thermoelectric materials by organic intercalation of layered transition metal dichalcogenide TiS 2'. Together they form a unique fingerprint.

Cite this