Multi-inch single-crystalline perovskite membrane for high-detectivity flexible photosensors

Abstract

Single crystalline perovskites exhibit high optical absorption, long carrier lifetime, large carrier mobility, low trap-state-density and high defect tolerance. Unfortunately, all single crystalline perovskites attained so far are limited to bulk single crystals and small area wafers. As such, it is impossible to design highly demanded flexible single-crystalline electronics and wearable devices including displays, touch sensing devices, transistors, etc. Herein we report a method of induced peripheral crystallization to prepare large area flexible single-crystalline membrane (SCM) of phenylethylamine lead iodide (C6H5C2H4NH3)2PbI4 with area exceeding 2500 mm2 and thinness as little as 0.6 μm. The ultrathin flexible SCM exhibits ultralow defect density, superior uniformity and long-term stability. Using the superior ultrathin membrane, a series of flexible photosensors were designed and fabricated to exhibit very high external quantum efficiency of 26530%, responsivity of 98.17 A W−1 and detectivity as much as 1.62 × 1015 cm Hz1/2 W−1 (Jones).

Enhanced On–Off Ratio Photodetectors Based on Lead‐Free Cs3Bi2I9 Single Crystal Thin Films

“…However, differing from the Cs 3 Bi 2 I 9 SCTF with a sharp absorption band edge, Cs 3 Bi 2 I 9 PCTF displays a distinct absorbance tail extending to 650 nm, which is ascribed to the transition involving sub‐bandgap state, indicating the presence of crystal disorder and high defect level in Cs 3 Bi 2 I 9 PCTF 18,32. As shown in the Figure 2b, a narrower PL peak with slightly redshifted peak position has featured in Cs 3 Bi 2 I 9 SCTF, reflecting the lower defect density and higher crystallinity 2,34,35…”

Reversible Thermochromism and Strong Ferromagnetism in Two‐Dimensional Hybrid Perovskites

“…Organic–inorganic hybrid halide perovskite materials have emerged as a new class of remarkable semiconductors for high‐performance optoelectronics . The majority of current research in this area is based on three‐dimensional (3D) perovskite structures, which have a general formula of ABX 3 , where A is monovalent cation, B is divalent metal cation, and X is halide .…”

Extremely Low Dark Current MoS2 Photodetector via 2D Halide Perovskite as the Electron Reservoir

“…Recently, organic–inorganic hybrid perovskites (OIHP) have emerged as promising photoactive materials for high‐performance optoelectronic devices due to their excellent optoelectronic properties (e.g., proper direct bandgap, broadband light absorption range, decent light absorption coefficient, and so on) . Moreover, organic–inorganic hybrid perovskites are compatible with the simple, low‐temperature, and low‐cost spin‐coating method .…”