title: Enhanced crystalline morphology of a ladder-type polymer bulk-heterojunction device by blade-coating.
abstract: A blade-coating process was employed to fabricate bulk-heterojunction (BHJ) polymer solar cells based on a ladder-type polymer (PIDT-PhanQ) with low crystallinity. Compared to the devices processed by a conventional spin-coating method, an intriguing morphology with enhanced phase-separation and increased crystallinity was achieved. As a result, power conversion efficiency up to 7.25% could be achieved from the blade-coated PIDT-PhanQ:PC71BM BHJ film, surpassing the original value obtained by spin-coating (6.29%). This improved photovoltaic performance is attributed to the improved charge carrier mobilities, which correlates well with the increased crystallinity and the organized network of the donor-acceptor phases that produce efficient charge-transporting pathways.
authors.affiliation: Department of Materials Science and Engineering, University of Washington, Seattle, WA 98195-2120, USA. ajen@u.washington.edu.
authors.forename: Jong H
authors.initials: JH
authors.lastname: Kim
authors.forename: Jae Woong
authors.initials: JW
authors.lastname: Jung
authors.forename: Spencer T
authors.initials: ST
authors.lastname: Williams
authors.forename: Feng
authors.initials: F
authors.lastname: Liu
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Russell
authors.forename: Alex K-Y
authors.initials: AK
authors.lastname: Jen