Open AccessMechanism of inverted polymer solar cells based on poly(dopamine)/ZnO as composite cathode buffer layer
Author(s) -
Qi Li,
Yong Zhang
Publication year - 2017
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.66.198201
Subject(s) - materials science , cathode , composite number , layer (electronics) , optoelectronics , polymerization , polymer solar cell , energy conversion efficiency , short circuit , polymer , solar cell , buffer (optical fiber) , open circuit voltage , active layer , chemical engineering , composite material , voltage , electrical engineering , thin film transistor , engineering
Inverted polymer solar cells with P3HT:PCBM as active layer are fabricated based on poly(dopamine)/ZnO (PDA/ZnO) as composite cathode buffer layer. Effects of PDA/ZnO composite cathode buffer layer with the different self-polymerization times on the device performance are investigated. According to the results, the short circuit current and photoelectric conversion efficiency of polymer solar cells first increase then decrease with the increase of the self-polymerization time of PDA. For 10-min PDA self-polymerization, the photovoltaic performance of the device achieves the optimal values:open circuit voltage 0.66 V, short circuit curent density 9.70 mA/cm2, fill factor 68.06%, and power conversion efficiency 4.35% under irratiation of light with a strength of 100 mW/cm2. We conclude that the improvement of device performance is due to the PDA/ZnO composite cathode buffer layer reduced the contact resistance between the ZnO and ITO, at the same time, the presence of a large number of nitrogen groups in PDA is advantageous for the electronic collection of the inverted polymer solar cells. Meanwhile, polymer solar cell with PDA/ZnO as composite cathode buffer layer also exhibits excelent stability. In addition, PDA has a strong adhesive force that makes the ZnO interface layer on its surface not easy to fall off. This provides a new way of fabricating the flexible polymer solar cell devices.