It is a great challenge to obtain broadband response perovskite photodetectors (PPDs) due to the relatively large bandgaps of the most used methylammonium lead halide perovskites. The response range of the reported PPDs is limited in the ultraviolet–visible range. Here, highly sensitive PPDs are successfully fabricated with low bandgap (≈1.25 eV) (FASnI3)0.6(MAPbI3)0.4perovskite as active layers, exhibiting a broadband response from 300 to 1000 nm. The performance of the PPDs can be optimized by adjusting the thicknesses of the perovskite and C60layers. The optimized PPDs with 1000 nm thick perovskite layer and 70 nm thick C60layer exhibit an almost flat external quantum efficiency (EQE) spectrum from 350 to 900 nm with EQE larger than 65% under −0.2 V bias. Meanwhile, the optimized PPDs also exhibit suppressed dark current of 3.9 nA, high responsivity (
- Award ID(s):
- 1748339
- NSF-PAR ID:
- 10060452
- Date Published:
- Journal Name:
- Oxide-based Materials and Devices IX
- Volume:
- 105331P
- Issue:
- 105331P
- Page Range / eLocation ID:
- 105331P
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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