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  • Passivating the interface between halide perovskite and SnO 2 by capsaicin to accelerate charge transfer and retard recombination
Title: Passivating the interface between halide perovskite and SnO 2 by capsaicin to accelerate charge transfer and retard recombination
Capsaicin is used to modify SnO 2 quantum dots and then used as an electron-transfer material for perovskite solar cells. After capsaicin modification, the power conversion efficiency of the devices increases from 19.90 (± 0.47)% to 21.87 (± 0.28)% with a champion device of 22.24% (AM 1.5G, 100 mW/cm 2 ). Transient photovoltage and photocurrent decay show that, after the capsaicin doping, the lifetime increases from 21.55 (± 1.54) to 27.63 (± 1.45)  μs, while the charge extraction time reduces from 1.90 (± 0.09) to 1.67 (± 0.06)  μs. Time-resolved photoluminescence and impedance spectrum studies show similar results. The accelerated charge transfer and retarded recombination are due to defect passivation. Space charge limited current study shows that, after modification, the trap density of devices is reduced from 2.24 × 10 15 to 1.28 × 10 15  cm −3 . X-ray photoelectron spectroscopy and theoretical calculation indicate that the reduced trap density is due to the chemical interaction between carbonyl group (from capsaicin) and Sn atom, and that between carbonyl group and Pb atom.  more » « less
Award ID(s):
1903962
PAR ID:
10325078
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Applied Physics Letters
Volume:
120
Issue:
10
ISSN:
0003-6951
Page Range / eLocation ID:
103503
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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