Highly Efficient and Ultrasensitive Large‐Area Flexible Photodetector Based on Perovskite Nanowires

Abstract

Hybrid organic–inorganic perovskites have shown exceptional semiconducting properties and microstructural versatility for inexpensive, solution‐processable photovoltaic and optoelectronic devices. In this work, an all‐solution‐based technique in ambient environment for highly sensitive and high‐speed flexible photodetectors using high crystal quality perovskite nanowires grown on Kapton substrate is presented. At 10 V, the optimized photodetector exhibits a responsivity as high as 0.62 A W−1, a maximum specific detectivity of 7.3 × 1012 cm Hz1/2 W−1, and a rise time of 227.2 µs. It also shows remarkable photocurrent stability even beyond 5000 bending cycles. Moreover, a deposition of poly(methyl methacrylate) (PMMA) as a protective layer on the perovskite yields significantly better stability under ambient air operation: the PMMA‐protected devices are stable for over 30 days. This work demonstrates a cost‐effective fabrication technique for high‐performance flexible photodetectors and opens opportunities for research advancements in broadband and large‐scale flexible perovskite‐based optoelectronic devices.

Ambient condition-processing strategy for improved air-stability and efficiency in mixed-cation perovskite solar cells

“…1 Their effective photon absorption, 2 low exciton binding energy, 3 and tunable bandgap (1.5-2.2 eV) 4 are advantageous for applications such as light-emitting diodes (LEDs), [5][6][7] photovoltaics (PVs) [8][9][10] and photodetector devices. [11][12][13] Albeit the remarkable progress from the past few years, organic-inorganic halide perovskite (OIHP) processing and its stability under ambient conditions remain an open challenge towards commercialization. The shelf-lifetime of OIHP, especially CH 3 NH 3 PbI 3 -based devices under ambient air conditions, is very short, 14 and their performances decrease rapidly due to the extrinsic and intrinsic instabilities of the halide perovskites.…”

Halide Perovskite Nanocrystals for Next‐Generation Optoelectronics

“…It is also known that the crystallization of PNCs is another key parameter in relation to stability . Yuan's group reported that smaller clusters of cuboid MAPbI 3 NCs are more stable than the larger ones .…”

Recent developments in flexible photodetectors based on metal halide perovskite

“…Figure E showed that the currents through MAPbI 3 NRs PDs under dark and irradiation conditions existed no significant decrease at different bending curvatures, proving the initial mechanical flexibility of MAPbI 3 NRs FPDs. In addition, Cloutier and co‐workers displayed the fabrication of 1D pseudohalide perovskite nanowires networks and their application in solution‐based large‐scale FPDs . PMMA film was spin‐coated on the perovskite layer to offer a passivation of the surface defects and/or protection from the environment.…”

“…D, I‐V curves of flexible photodetectors with/without PMMA protective layer under dark and light states. Reproduced with permission . Copyright 2018, WILEY‐VCH.…”