Enhancing doping efficiency by improving host-dopant miscibility for fullerene-based n-type thermoelectrics. Issue 40 (28th September 2017)

• Record Type: Journal Article
• Authors: Qiu, Li; Liu, Jian; Alessandri, Riccardo; Qiu, Xinkai; Koopmans, Marten; Havenith, Remco W. A.; Marrink, Siewert J.; Chiechi, Ryan C.; Anton Koster, L. Jan; Hummelen, Jan C.
• Is Part Of: Journal of materials chemistry. Volume 5:Issue 40(2017)
• Page Start: 21234
• Page End: 21241
• Publication Date: 2017-09-28
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c7ta06609k
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Improved miscibility of the blend could be obtained by controlling the structural similarity between the dopant and host materials, which accounts for the high doping efficiency and good thermoelectric performance. Abstract : This paper describes a promising n-type doping system with high performance for thermoelectric applications. By introducing the polar triethylene glycol (TEG) side chain onto both fullerene host (PTEG-1) and dopant (TEG-DMBI) materials, the TEG-DMBI doped PTEG-1 films obtained through solution processing provide a better miscibility compared with films doped with commercially available N-DMBI (bearing a dimethylamino group instead of TEG), as determined by phase imaging AFM (atomic force microscopy) measurements and coarse-grain molecular dynamics simulations, leading to high doping efficiency up to 18% at 20 mol% doping concentration and thus high carrier density and mobility, which are critical to the electrical conductivity. Therefore a record power factor of 19.1 μW m −1 K −2 is obtained with an electrical conductivity of 1.81 S cm −1, one of the highest values reported for solution processable fullerene derivatives as n-type organic materials for thermoelectric applications to date.