In the past years, hybrid perovskite materials have attracted great attention due to their superior optoelectronic properties. In this study, the authors report the utilization of cobalt (Co2+) to partially substitute lead (Pb2+) for developing novel hybrid perovskite materials, CH3NH3Pb1‐
Organic–inorganic halide perovskites are promising photodetector materials due to their strong absorption, large carrier mobility, and easily tunable bandgap. Up to now, perovskite photodetectors are mainly based on polycrystalline thin films, which have some undesired properties such as large defective grain boundaries hindering the further improvement of the detector performance. Here, perovskite thin‐single‐crystal (TSC) photodetectors are fabricated with a vertical p–i–n structure. Due to the absence of grain‐boundaries, the trap densities of TSCs are 10–100 folds lower than that of polycrystalline thin films. The photodetectors based on CH3NH3PbBr3and CH3NH3PbI3TSCs show low noise of 1–2 fA Hz−1/2, yielding a high specific detectivity of 1.5 × 1013cm Hz1/2W−1. The absence of grain boundaries reduces charge recombination and enables a linear response under strong light, superior to polycrystalline photodetectors. The CH3NH3PbBr3photodetectors show a linear response to green light from 0.35 pW cm−2to 2.1 W cm−2, corresponding to a linear dynamic range of 256 dB.
more » « less- NSF-PAR ID:
- 10039473
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 29
- Issue:
- 39
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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