skip to main content

Title: Carrier injection dynamics in heterojunction solar cells with bipolar molecule

A boron subphthalocyanine chloride (SubPc) is a bipolar molecule and is used in hetero-junction organic solar cells. Here, we investigated the carrier injection dynamics from the donor α-sexithiophene (6T) or acceptor C{sub 60} layers to the bipolar SubPc layer by means of the femtosecond time-resolved spectroscopy. We observed gradual increase of the SubPc{sup –} (SubPc{sup +}) species within ≈300 ps. The increases are interpreted in terms of the exciton diffusion within the 6T (C{sub 60}) layer and subsequent electron (hole) injection at the interface. In 6T/SubPc heterojunction, the electron injection is observed even at 80 K. The robust electron injection is ascribed to the efficient charge separation within the 6T layer under photo exciation at 400 nm.
Authors:
;  [1] ;  [2] ;  [1] ;  [3]
  1. Graduate School of Pure and Applied Science, University of Tsukuba, Tsukuba 305-8571 (Japan)
  2. Photovoltaic Materials Unit, National Institute for Materials Science (NIMS), Tsukuba 305-0047 (Japan)
  3. (CiRfSE), University of Tsukuba, Tsukuba 305-8571 (Japan)
Publication Date:
OSTI Identifier:
22398793
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 12; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BORON CHLORIDES; CHARGE CARRIERS; DIFFUSION; ELECTRIC CONTACTS; ELECTRON BEAM INJECTION; EXCITONS; FULLERENES; HETEROJUNCTIONS; HOLES; INTERFACES; LAYERS; MOLECULES; ORGANIC SOLAR CELLS; PHTHALOCYANINES; SPECTROSCOPY; TIME RESOLUTION