Doped In2O3 inverse opals as photoanode for dye ...

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Mar 20, 2015 - current (Jsc) increased largely with the increasing pore size of the IOs ... that the modification of band gap in the Tm and Yb doped In2O3 IOs is ...
Journal of Colloid and Interface Science 450 (2015) 196–201

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Journal of Colloid and Interface Science www.elsevier.com/locate/jcis

Doped In2O3 inverse opals as photoanode for dye sensitized solar cells Lingxin Kong, Qilin Dai ⇑, Chuang Miao, Lin Xu, Hongwei Song ⇑ State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, People’s Republic of China

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Article history: Received 6 February 2015 Accepted 10 March 2015 Available online 20 March 2015 Keywords: Inverse opals Dye sensitized solar cells In2O3

a b s t r a c t One promising way to improve the power conversion efficiency (PCE) of dye-sensitized solar cells (DSSCs), which have attracted great interest due to their low cost, is modifying the working electrode. In this work, Tm and Yb doped as well as undoped In2O3 inverse opals (IOs) were synthesized by the sol–gel method. DSSCs based on In2O3, In2O3:Tm and In2O3:Yb IOs as photoanodes were fabricated and studied. It is observed that the device performance including open-circuit voltage (Voc) and short-circuit current (Jsc) increased largely with the increasing pore size of the IOs and the introduction of Tm and Yb elements in the In2O3 lattices. The PCE of the DSSC was increased from 0.33% to 0.96% when the ln2O3 IOs photoanode was substituted by ln2O3:Yb IOs. The electrochemical impedance spectroscopy (EIS) measurements indicate that the modification of band gap in the Tm and Yb doped In2O3 IOs is significant for the improved performance, which can effectively suppress the charge transfer recombination and improve the electron lifetime. Ó 2015 Elsevier Inc. All rights reserved.

1. Introduction DSSCs have attracted much interest due to the low cost and possibilities to create flexible devices [1,2], and the highest efficiency to date of a DSSC is 12.7% [2]. Semiconductor photoanode is an important part of a DSSC that transport electrons to fluorine ⇑ Corresponding authors. E-mail addresses: [email protected] (Q. Dai), [email protected] (H. Song). http://dx.doi.org/10.1016/j.jcis.2015.03.024 0021-9797/Ó 2015 Elsevier Inc. All rights reserved.

doped tin oxide (FTO) [3,4]. Due to its high PCE and easy preparation [2], the mesoporous TiO2 nanoparticles have been widely utilized as photoanode in DSSCs. However, the development of promising photoanode that shows solar cell performance is still crucial for the application of DSSCs. Some semiconductor materials, which have lower conduction band edge potential and higher electron mobility, have the potential application in DSSCs, because lower conduction band edge potential might be required to match with certain dye molecules having lower lowest unoccupied