2D Perovskite Single‐Crystalline Photodetector with Large Linear Dynamic Range for UV Weak‐Light Imaging

Abstract

Weak‐light imaging holds immense significance in various imaging applications. Recently, there has been significant research focused on 2D perovskites for photodetectors (PDs), owing to their superior photoelectric properties. However, the utilization of 2D perovskites for high‐performance weak‐light detection remains limited, and there is a notable absence of demonstration in weak‐light ultraviolet (UV) imaging. Herein, a high‐sensitive UV detectors with an ultra‐low detection limit for weak‐light imaging are demonstrated, utilizing 2D perovskite (PA)2PbBr4 (PPB) single crystals (SCs). Leveraging the exceptional quality of SCs, the PPB‐based PD exhibits outstanding operational performances, including a low dark current of 0.735 pA, high on/off ratio of 4150 under 263.3 mW cm−2 illimitation, and extensive linear dynamic range of 153.61 dB, which is currently the highest reported value among 2D perovskite SC detectors. Notably, PPB PDs demonstrate a remarkable response under 5.49 nW cm−2 illumination, enabling it to exhibit outstanding photo‐response with an excellent detectivity of 2.3 × 1013 Jones and responsivity of 2.22 A W−1. Importantly, high‐resolution images are successfully obtained under weak‐light illumination. These findings underscore the immense potential of 2D perovskite for UV weak‐light imaging.

Light-Triggered Anti-ambipolar Transistor Based on an In-Plane Lateral Homojunction

“…A comparison with previously reported weak light detectors is presented in Figure d. Our WSe 2 AAT demonstrates comparable to or even better responsivity and detectivity compared to those of previously reported weak light detectors − (see Table S2).…”

“…The high sensitivity of the WSe 2 AAT to weak light can be attributed to the following main factors. First, the device exhibits low dark current in the pA range, thereby demonstrating high sensitivity, − as depicted in the inset of Figure a. Second, when light-triggered anti-ambipolar transport occurs, the entire WSe 2 channel serves as a photosensitive area.…”

Modulating Dimensionality of 2D Perovskite Layers for Efficient and Stable 2D/3D Perovskite Photodetectors

“…Based on the significantly improved performance after 2D layer post-treatment, we expect the passivated devices to exhibit a lower weak light detection limit. Thus, LDR was investigated, which reflects the light intensity range in which the devices have a linear response capability, expressed as LDR = 20 log­( J max / J min ), where J max and J min are the superior and inferior limits of photocurrent density in the linearity range and the limits are defined by nonlinear responses or damage problems. , As shown in Figure a–c, the photocurrent was depicted at different intensities under the illumination of 532 nm light. The LDR value of IPA-BAI PD reached 120 dB, surpassing the 102 dB of the control PD and the 113 dB of ACN-BAI PD.…”

Micro/Nano Perovskite Materials for Advanced X-ray Detection and Imaging

“…Over the past decade, perovskite micro-/nanostructure devices have made significant strides in their development. Micro/nano arrays have shown outstanding optoelectronic performance attributed to their confined and directional carrier transport, high crystalline quality, and low defect density. − Various fabrication methods have been employed to create these micro/nano perovskite arrays on bulk materials, including epitaxy growth, − template-assisted imprinting, and focused ion beam assisted etching . These methods have helped to realize excellent perovskite micro-/nanostructure devices successfully, releasing their potential for a variety of applications in optoelectronics and other fields.…”