High‐Quality CsAg₂I₃Microwires Grown by Spatial Confinement Method for Self‐Powered UV Photodetectors

Abstract

Recently, lead halide perovskites arouse intensive attentions in photoelectric fields owing to their low trap state density, high carrier mobility, large extinction coefficient, and low‐temperature solution processing technique. However, their future commercial development is severely hampered by the lead toxicity and instability. Although lead‐free metal‐halide perovskites recently have been extensively studied in optoelectronics, their low‐dimensional counterparts can further expand their novel optical and electronic properties for potential applications. In this work, the planar growth of one‐dimensional (1D) CsAg2I3 single‐crystal microwires (MWs) on diverse substrates by space‐confined method is reported. The growth kinetic process of CsAg2I3 single‐crystal MWs is elucidated by in situ observation. Furthermore, the CsAg2I3 single‐crystal MWs exhibit potential applications in ultraviolet light photodetectors as a photoactive layer. The fabricated heterojunction photodetector exhibits pronounced photoelectric performances working in self‐powered mode, including a specific detectivity of 2.09 × 108 Jones, a high responsivity of 26.5 mA W−1, and fast response speed of 258.43/289.32 ms under light illumination of 265 nm, due to the high crystallinity and effective photogenerated carrier transfer. This study provides a vital insight into the rational design of low‐dimensional perovskites for versatile optoelectronic applications.

Integration of One-Dimensional (1D) Lead-Free Perovskite Microbelts onto Silicon for Ultraviolet–Visible–Near-Infrared (UV-vis-NIR) Heterojunction Photodetectors

“…As shown in Figure 1g, the XRD pattern of individual CAI belts represented by the green line shows four diffraction peaks at 10.33°, 20.70°, 31.23°, and 42.10°, corresponding to the (110), (220), (330), and (440) crystal planes of CAI, respectively. 50 The highly oriented four diffraction peaks match well with the reference. 51 Besides, the XRD rocking curves were conducted using a high-resolution Xray interferometer to demonstrate the quality of crystals.…”

“…The crystal structures of CAI before and after the formation of heterojunctions was checked by X-ray diffraction (XRD). As shown in Figure g, the XRD pattern of individual CAI belts represented by the green line shows four diffraction peaks at 10.33°, 20.70°, 31.23°, and 42.10°, corresponding to the (110), (220), (330), and (440) crystal planes of CAI, respectively . The highly oriented four diffraction peaks match well with the reference .…”

Plasmon-enhanced photoresponse and stability of a CsPbBr3 microwire/GaN heterojunction photodetector with surface-modified Ag nanoparticles

“…Thus, the electrical properties of our synthesized CsPbBr 3 MW are n-type. 15,40,46 To study the photoresponse properties, the as-fabricated single CsPbBr 3 MW MSM device was exposed to a 405 nm light source (a normal LED). The I – V curve (red solid line) was also plotted in Fig.…”

“…Individual CsPbBr 3 MWs were synthesized using an in-plane solution method. 44–47 First, the samples of 0.5 mM CsBr and 0.5 mM PbBr 2 were mixed in 1 mL dimethyl sulfoxide (DMSO). Second, the mixed solution was processed in a magnetic stirring heater at 70 °C for 8 h while stirring.…”

Improving Optoelectronic Properties of Ternary Silver Chlorides via Defect Engineering

“…In the recent decade, hybrid lead halide perovskites, especially those with low-dimensional crystal structures, have emerged as promising luminescent materials with promising applications in light-emitting diodes, radiation detection, and anticounterfeiting applications. − The exceptional optoelectronic properties can be attributed to the unique electronic structure and material characteristics, which feature a minimized grain boundary and trap density. Despite their excellent optoelectronic properties, the toxicity of lead and the poor stability of lead halides in ambient environments are still considered as the bottleneck issue in this field. − Correspondingly, extensive efforts have been dedicated to the search for lead-free alternatives. − Recently, all-inorganic ternary Ag­(I) halides (A 2 AgX 3 with a chained structure and AAgX 2 with a layered structure, A = Rb, Cs; X = Cl, Br, I) have gained much attention due to their attractive features, such as lead-free nature, remarkable stability in ambient conditions, and tunable light emission properties. − High-purity and crystalline characteristics are crucial for the optoelectronic properties of ternary silver chloride materials. Notably, these materials exhibit large Stokes shifts and broad-band emissions that cover almost the entire visible range.…”