Aqueous Solution Processed, Ultrathin ZnO Film with Low Conversion Temperature as the Electron Transport Layer in the Inverted Polymer Solar Cells

详细信息    查看全文

• 作者：Yawen Chen ; Zhanhao Hu ; Zhiming Zhong ; Wen Shi ; Junbiao Peng ; Jian Wang ; Yong Cao
• 刊名：Journal of Physical Chemistry C
• 出版年：2014
• 出版时间：September 25, 2014
• 年：2014
• 卷：118
• 期：38
• 页码：21819-21825
• 全文大小：367K
• ISSN：1932-7455

文摘

Ultrathin ZnO layer of ca. four nm thick deposited from an aqueous zinc oxide hydrate (ZnO路xH₂O) solution is developed as the electron transport layer (ETL) in the inverted polymer solar cells (PSCs). Because of the low energy metal鈥揳mmine dissociation and hydroxide condensation/dehydration chemistry, a conversion temperature (T_A) as low as 80 掳C is achieved. With the active layer of poly(N-9鈥?hepta-decanyl-2,7-carbazole-alt-5,5-(4鈥?7鈥?di-2-thienyl-3鈥?2鈥?1鈥?benzothiadiazole)) doped with [6,6]-phenyl C₇₁ butyric acid methyl ester (PCDTBT:PC₇₁BM), the average power conversion efficiency of the devices is up to 6.48%, and the short circuit current density reaches 11.4 mA cm^鈥?. In comparison, the devices with traditional sol鈥揼el processed ZnO electron transport layer has a power conversion efficiency of 5.53% at an annealing temperature of 200 掳C. The device performance improvement is attributed to the better charge transportation and smoother surface of the ZnO film deposited from ZnO路xH₂O aqueous solution. The simple solution preparation and the facile device fabrication, combined with the low conversion temperature make the aqueous ZnO路xH₂O one of the best candidates for ETL in the inverted PSCs fabricated on low cost, flexible substrates.