Two-Dimensional Cs₂Pb(SCN)₂Br₂-Based Photomemory Devices Showing a Photoinduced Recovery Behavior and an Unusual Fully Optically Driven Memory Behavior

Abstract

The rapid development of Internet of Things and big data has made the conventional storage devices face the need of reforming. Rather than using electrical pulses to store data in one of two states, photomemory exploiting optical stimulation to store light information emerges as a revolutionary candidate for the optoelectronic community. However, fully optically driven photomemory with fast data transmission speed and outstanding energy saving capability suffers from less exploration. Herein, a transistortype photomemory using a 2D Cs 2 Pb(SCN) 2 Br 2 /polymer hybrid floating gate is explored and three host polymers, polystyrene, poly(4-vinylphenol), and poly(vinylpyrrolidone) (PVP), are investigated to understand the relationship between polymer matrix selection and memory performance. All devices show a photoinduced recovery memory behavior but with two distinctly different photomemory behaviors. In addition to the demonstration of a regular nonvolatile photomemory showing a high on/off ratio of >10 6 over 10 4 s, an unusual fully optically driven memory behavior is intriguingly accomplished in the Cs 2 Pb(SCN) 2 Br 2 /PVP photomemory. Using white light as the driver of programming and a blue laser as the main performer of erasing, this device can be switched between two distinguishable states and possesses acceptable data discriminability, as evidenced by its fully optically driven writing (programing)-reading-erasing-reading switching function that shows an on/off current ratio of 10 3 . This study not only presents the first 2D perovskite-based photomemory but also shows a novel fully optically driven memory that has been rarely reported in the literature.

Design of two-dimensional halide perovskite composites for optoelectronic applications and beyond

“…149,150 Through space constraints, perovskite nanocrystals embedded in the polymer matrix may act as charge trapping sites to isolate charges, and the related trapping/untrapping mechanisms can be realized by applying an electric field or using photons. Chueh et al 151 created a transistor memory through Cs 2 Pb(SCN) 2 Br 2 /polymer (SCN -= thiocyanide) hybrid films. The 2D Cs 2 Pb(SCN) 2 Br 2 with intrinsic QW structure exhibited not only considerable photoresponse but also good environmental stability.…”

Halide perovskite for low‐power consumption neuromorphic devices

“…(C) WRER switching cycle of fully optically driven Cs 2 Pb(SCN) 2 Br 2 /PVP‐based photomemory recorded at V DS = −60 V. Note that the gray shadow, blue shadow, and yellow shadow represent the dark conditions and illumination period of blue laser and white light, respectively. (B),(C) Reproduced with permission: Copyright 2020, American Chemical Society 72 . (D) The schematic device structure of the perovskite flash memory.…”

“…Liao et al reported fully optically driven photomemory based on 2D Cs 2 Pb(SCN) 2 Br 2 72 . Figure 6B shows the device structure of the memory device which consisted of Si/SiO 2 /perovskite‐polymer/pentacene/electrodes.…”

Flexible and Energy-efficient Synaptic Transistor with Quasi-linear Weight Update Protocol by Inkjet Printing of Orientated Polar-electret/High-k Oxide Hybrid Dielectric

“…Signi cantly, the achieving of su cient dielectric states is still a burden even for noninkjet-printed synaptic transistors, although tremendous contributions have already been made to achieve the nonvolatile behavior based on diverse kinds of dielectric materials (ferroelectric 11,12 , electret [13][14][15] , electrochemical 16,17 , two-dimensional [18][19][20] , hybrid materials [21][22][23] , etc.) and structures ( oating gate [24][25][26][27][28][29][30] , heterojunction 31-34 , etc. ).…”