Sensitive Deep Ultraviolet Photodetector and Image Sensor Composed of Inorganic Lead-Free Cs₃Cu₂I₅ Perovskite with Wide Bandgap

Abstract

In this work, a sensitive deep ultraviolet (DUV) light photodetector based on inorganic and lead-free Cs 3 Cu 2 I 5 crystalline film derived by a solution method was reported. Optoelectronic characterization revealed that the perovskite device exhibited nearly no sensitivity to visible illumination with wavelength of 405 nm but exhibited pronounced sensitivity to both DUV and UV light illumination with response speeds of 26.2/49.9 ms for rise/fall time. The I light /I dark ratio could reach 127. What is more, the responsivity and specific detectivity were calculated to be 64.9 mA W −1 and 6.9 × 10 11 Jones, respectively. In addition, the device could keep its photoresponsivity after storage in air environment for a month. It is also found that the capability of Cs 3 Cu 2 I 5 crystalline film device can readily record still DUV image with acceptable resolution. The above results confirm that the DUV photodetector may hold great potential for future DUV optoelectronic device and systems.

Lead-Free Perovskites for Lighting and Lasing Applications: A Minireview

“…The synthesized NCs demonstrated strong excitation-independent emission and high PLQY of 58%. In this work [54], a synthesis of all-inorganic Cs 3 Cu 2 I 5 perovskite crystalline film via a spin-coating method was reported. The Cs 3 Cu 2 I 5 thin film was formed from CsI and CuI precursors sequentially added into a mixed solvent of dimethyl sulfoxide (DMSO) and dimethylformamide (DMF).…”

Copper Iron Sulfide Nanocrystal‐Bulk Silicon Heterojunctions for Broadband Photodetection

“…Efficient detection of photons lies at the heart of several modern technologies. [ 1 ] Although specialized high‐sensitivity detectors for specific wavelength ranges exist, [ 2–6 ] of late, there has been significant interest for the development of broadband photodetectors (PDs) for hyperspectral sensing. [ 7–12 ] Sensing over a very broad wavelength range is potentially very important for imaging applications, since it can enable for the identification of multiple parameters including morphology, temperature, chemical composition, etc.…”

Emerging Perovskite Materials with Different Nanostructures for Photodetectors

“…Furthermore, considering the environmental issue, some scientists developed lead‐free perovskite materials, such as Cs 3 Cu 2 I 5 , CsBi 3 I 10, and FASnI 3 in forms of films, nanowires, quantum dots, etc., for photodetector applications. [ 33–35 ] Since the structures of perovskites are largely determined by the synthetic method, in this section we will discuss some representative synthetic strategies used for the preparation of perovskites for photodetectors.…”