title: Tuning open-circuit voltage in organic solar cells by magnesium modified Alq(3).
abstract: The low molecular weight tris-(8-hydroxyquinoline) aluminum (Alq(3)) has been incorporated with magnesium (Mg) that altered the nature of its opto-electronic characteristics. The lowering of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) in Mg:Alq(3), compared to pure Alq(3), creates a stronger field (exceeding the exciton binding energy) at the donor-acceptor junction to dissociate the photo-generated exciton and also provides a low barrier for electron transport across the device. In an electron-only device (described in the text), a current enhancement in excess of 10(3), with respect to pure Alq(3), could be observed at 10 V applied bias. Optimized Mg:Alq(3) layer, when introduced in the photovoltaic device, improves the power conversion efficiencies significantly to 0.15% compared to the pure Alq(3) device. The improvement in the photovoltaic performance has been attributed to the superior exciton dissociation and carrier transport.
authors.forename: Chi-Ta
authors.initials: CT
authors.lastname: Chou
authors.forename: Chien-Hung
authors.initials: CH
authors.lastname: Lin
authors.forename: Meng-Hsiu
authors.initials: MH
authors.lastname: Wu
authors.forename: Tzu-Wei
authors.initials: TW
authors.lastname: Cheng
authors.forename: Jiun-Haw
authors.initials: JH
authors.lastname: Lee
authors.forename: Chin-Hsin J
authors.initials: CH
authors.lastname: Liu
authors.forename: Yian
authors.initials: Y
authors.lastname: Tai
authors.forename: Surojit
authors.initials: S
authors.lastname: Chattopadhyay
authors.forename: Juen-Kai
authors.initials: JK
authors.lastname: Wang
authors.forename: Kuei-Hsien
authors.initials: KH
authors.lastname: Chen
authors.forename: Li-Chyong
authors.initials: LC
authors.lastname: Chen
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