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Title: Mesoporous scaffolds based on TiO 2 nanorods and nanoparticles for efficient hybrid perovskite solar cells
In a mesoporous hybrid perovskite solar cell (PSC), the mesoporous scaffold plays key roles in controlling the crystallization of the perovskite material and in the charge carrier transport, and hence is critical for developing highly efficient PSCs. Here we report a study on blending micrometer-long TiO 2 nanorods (NRs) into the commonly used nanoparticles (NPs) to optimize the mesoporous structure, with the aim of enhancing the perovskite material loading and connectivity as well as light harvesting. It was found that with 5–10% of NR incorporation, a uniform scaffold can be spin-coated and the PSC performance was improved. In comparison to the pure NP-based device, the power conversion efficiency was increased by about 27% when 10% of the NRs were incorporated, due to enhanced light harvesting and charge collection. However, with more NR blending, a homogeneous scaffold cannot be formed, resulting in PSC performance degradation. These findings contribute to a better design of mesoporous scaffolds for high-performance PSCs.  more » « less
Award ID(s):
1438681
PAR ID:
10074466
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry A
Volume:
3
Issue:
48
ISSN:
2050-7488
Page Range / eLocation ID:
24315 to 24321
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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