Sn‐Based Perovskite for Highly Sensitive Photodetectors

Abstract

Organic–inorganic hybrid perovskites have emerged as promising functional materials for high‐performance photodetectors. However, the toxicity of Pb and the lack of internal gain mechanism in typical perovskites significantly hinder their practical applications. Herein, a low‐voltage and high‐performance photodetector based on a single layer of lead‐free Sn‐based perovskite film is reported. The device shows broadband response from ultraviolet to near‐infrared light with a responsivity up to 10 5 A W −1 and a high gain at a low operating voltage. The outstanding performance is attributed to the high hole mobility, p‐doping nature, and excellent optoelectronic properties of the Sn‐based perovskite. Moreover, the device is assembled on a flexible substrate and demonstrates both high sensitivity and good bending stability. This work demonstrates a route for realizing nontoxic, low‐cost, and high‐performance perovskite photodetectors with a simple device structure.

Perovskite‐Based Phototransistors and Hybrid Photodetectors

“…Although alternative elements including tin, copper, and germanium have been employed to replace lead, the optoelectronic performance of the resultant devices based on these perovskites are far from satisfactory at the current stage. Notably, our recent work clearly demonstrates that FASnI 3 is an ideal lead‐free perovskite material for highly sensitive photodetectors due to its high carrier mobility . Future studies on their photophysical mechanism and approaches for improving optoelectronic characteristics are essentially required.…”

“…3D perovskite‐MAPbX 3 phototransistors could be a hot topic for investigation because of high‐performance, but toxic Pb 2+ elements, sensitivity to moisture and oxygen, and thermal instability have reduced interests for further developments . In contrary, 2D perovskites have exhibited abundant and tunable optoelectronic properties, high quantum efficiency, and large specific surface area, leading to enhancements of a range of electronic and optical applications .…”

High‐Performance Quasi‐2D Perovskite/Single‐Walled Carbon Nanotube Phototransistors for Low‐Cost and Sensitive Broadband Photodetection

“…[ 4,5 ] In recent years, organic–inorganic hybrid perovskites (OIHPs) have emerged as promising candidate materials for next‐generation photodetectors because of their unique properties, such as high optical absorption coefficient, easily tunable bandgap, high carrier diffusion length, and excellent defect tolerance. [ 6–15 ] However, the simple photoconductors based on typical OIHPs are relatively limited due to the absence of external gain mechanism and the abundant grain boundaries in perovskite thin films, despite the fact that they can be fabricated very conveniently. [ 16–18 ] For instance, Hu and his co‐workers developed a photoconductor based on MAPbI 3 with a responsivity of 3.49 A W −1 .…”

Recent developments in flexible photodetectors based on metal halide perovskite

“…Currently, nontoxic or low‐toxic elements (e.g., Sn, Sb, Bi) have been used to replace Pb element in the perovskites for decreasing the toxicity to both the humans and environment . For instance, Yan's group fabricated high performance PDs based on FASnI 3 perovskite, in which FASnI 3 is stable owing to the addition of hydroxybenzene sulfonic acid . Although great progresses have been made in MHPs, major breakthroughs still need to be achieved.…”