title: A new method to disperse CdS quantum dot-sensitized TiO2 nanotube arrays into P3HT:PCBM layer for the improvement of efficiency of inverted polymer solar cells.
abstract: We report that the efficiency of ITO/nc-TiO2/P3HT:PCBM/MoO3/Ag inverted polymer solar cells (PSCs) can be improved by dispersing CdS quantum dot (QD)-sensitized TiO2 nanotube arrays (TNTs) in poly (3-hexylthiophene) and [6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM) layer. The CdS QDs are deposited on the TNTs by a chemical bath deposition method. The experimental results show that the CdS QD-sensitized TNTs (CdS/TNTs) do not only increase the light absorption of the P3HT:PCBM layer but also reduce the charge recombination in the P3HT:PCBM layer. The dependence of device performances on cycles of CdS deposition on the TNTs was investigated. A high power conversion efficiency (PCE) of 3.52% was achieved for the inverted PSCs with 20 cyclic depositions of CdS on TNTs, which showed a 34% increase compared to the ITO/nc-TiO2/P3HT:PCBM/MoO3/Ag device without the CdS/TNTs. The improved efficiency is attributed to the improved light absorbance and the reduced charge recombination in the active layer.
authors.affiliation: Key Laboratory of Photovoltaic Materials, Department of Physics and Electronics, Henan University, Kaifeng 475004, People's Republic of China.
authors.forename: Fumin
authors.initials: F
authors.lastname: Li
authors.affiliation: Key Laboratory of Photovoltaic Materials, Department of Physics and Electronics, Henan University, Kaifeng 475004, People's Republic of China.
authors.forename: Chong
authors.initials: C
authors.lastname: Chen
authors.affiliation: Key Laboratory of Photovoltaic Materials, Department of Physics and Electronics, Henan University, Kaifeng 475004, People's Republic of China.
authors.forename: Furui
authors.initials: F
authors.lastname: Tan
authors.affiliation: Key Laboratory of Photovoltaic Materials, Department of Physics and Electronics, Henan University, Kaifeng 475004, People's Republic of China.
authors.forename: Gentian
authors.initials: G
authors.lastname: Yue
authors.affiliation: Department of Electronic Science and Engineering, Jilin University, Changchun 130012, People's Republic of China.
authors.forename: Liang
authors.initials: L
authors.lastname: Shen
authors.affiliation: Key Laboratory of Photovoltaic Materials, Department of Physics and Electronics, Henan University, Kaifeng 475004, People's Republic of China.
authors.forename: Weifeng
authors.initials: W
authors.lastname: Zhang
keywords: Inverted; Nanotube; Polymer solar cells; Quantum dot