title: Efficient "light-soaking"-free inverted organic solar cells with aqueous solution processed low-temperature ZnO electron extraction layers.
abstract: Low-temperature processes are unremittingly pursued in the fabrication of organic solar cells. The paper reports that the highly efficient and "light-soaking"-free inverted organic solar cell can be achieved by using ZnO thin films processed from the aqueous solution method at a low temperature. The inverted organic solar with an aqueous-processed ZnO thin film annealed at 150 °C shows an efficiency of 3.79%. Even when annealed at a temperature as low as 80 °C, the device still shows an efficiency of 3.71%. With the proper annealing temperature of 80 °C, the flexible device, which shows an efficiency of 3.56%, is fabricated on PET. This flexible device still keeps the efficiency above 3.40% after bent for 1000 times with a curvature radius of 50 mm. In contrast, a low annealing temperature leads to an inferior device performance when the ZnO thin film is processed from the widely used sol-gel method. The device with sol-gel processed ZnO annealed at 150 °C only shows a PCE of 1.3%. Furthermore, the device shows a strong "light-soaking" effect, which is not observed in the device containing an aqueous-processed ZnO thin film. Our results suggest that the adopted aqueous solution method is a more efficient low temperature technique, compared with the sol-gel method.
authors.affiliation: State Key Laboratory of Wide Bandgap Semiconductor Technology School Of Microelectronics, Xidian University , 2 South Taibai Road, Xi'an, China 710071.
authors.forename: Wei
authors.initials: W
authors.lastname: Wei
authors.forename: Chunfu
authors.initials: C
authors.lastname: Zhang
authors.forename: Dazheng
authors.initials: D
authors.lastname: Chen
authors.forename: Zhizhe
authors.initials: Z
authors.lastname: Wang
authors.forename: Chunxiang
authors.initials: C
authors.lastname: Zhu
authors.forename: Jincheng
authors.initials: J
authors.lastname: Zhang
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Lu
authors.forename: Yue
authors.initials: Y
authors.lastname: Hao
mesh_terms: D004583:Electrons; D005782:Gels / Q000737:chemistry; D011137:Polystyrenes / Q000737:chemistry; D012993:Solar Energy; D013696:Temperature; D013876:Thiophenes / Q000737:chemistry; D014867:Water / Q000737:chemistry; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D005782:Gels; D011137:Polystyrenes; D013876:Thiophenes; C533756:poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate); D014867:Water; D015034:Zinc Oxide