Polarization‐Driven Self‐Powered Photodetection in a Single‐Phase Biaxial Hybrid Perovskite Ferroelectric

Abstract

Self‐powered photodetection driven by ferroelectric polarization has shown great potential in next‐generation optoelectronic devices. Hybrid perovskite ferroelectrics that combine polarization and semiconducting properties have a promising position within this portfolio. Herein, we demonstrate the realization of self‐powered photodetection in a new developed biaxial ferroelectric, (EA)2(MA)2Pb3Br10 (1, EA is ethylammonium and MA is methylammonium), which displays high Curie temperature (375 K), superior spontaneous polarization (3.7 μC cm−2), and unique semiconducting nature. Strikingly, without an external energy supply, 1 exhibits an direction‐selectable photocurrent with fascinating attributes including high photocurrent density (≈4.1 μA cm−2), high on/off switching ratio (over 106), and ultrafast response time (96/123 μs); such merits are superior to those of the most active ferroelectric oxide BiFeO3. Further studies reveal that strong inversion symmetry breaking in 1 provides a desirable driving force for carrier separation, accounting for such electrically tunable self‐powered photoactive behaviors. This work sheds light on exploring new multifunctional hybrid perovskites and advancing the design of intelligent photoelectric devices.

Highly Sensitive and Tunable Self-Powered UV Photodetectors Driven Jointly by p-n Junction and Ferroelectric Polarization

“…Table summarizes the FE-based photodetector performance. The performance parameters of our device are superior to those of most reported FE-based devices, such as those based on sole bulk PV effect, on combining PV and pyroelectric effect and on PV-pyroelectric-piezoelectric coupling effect. ,− ,− Our device also exhibits better performance than previously reported semiconductor-based photodetectors , as well as newly developed photodetectors of biaxial hybrid perovskite FE, (EA) 2 (MA) 2 Pb 3 Br 10 (EA is ethylammonium, MA is CH 3 NH 3 + ) . This suggests that combining E p‑n and E dp is a promising way to improve device performance.…”

Stimuli-responsive switchable halide perovskites: Taking advantage of instability

“…Analogous effects due to cation reorientations have been observed in 2D perovskites as well, such as (BZA)2PbCl4 (where BZA + is benzylammonium), (CHA)2PbBr4 (where CHA + is cyclohexylammonium), (AMP)PbI4 (where AMP 2+ is 4-(aminomethyl)piperidinium) (Figure 3 D), and others. [64][65][66][67][68][69][70][71][72][73][74][75][76][77][78][79][80][81][82] Importantly, such cation reorientations may also be accompanied with structural changes of the inorganic framework. In particular, copper-based 2D perovskites undergo strong Jahn-Teller distortions upon temperature changes.…”

“…An analogous ferroelectric-to-paraelectric transition due to cation disordering was also observed in 2D perovskites (Figure 8 A). [64][65][66][67][68][69][70][71][72][73][74][75][76][77][78][79][80][81][82] Interestingly, in addition to ferroelectric behavior, such 2D perovskites also display semiconducting properties which could be useful for next-generation applications. For instance, ferroelectric photovoltaic devices would be able to produce anomalous high open-circuit voltages and efficient charge separation due to the built-in field of the ferroelectric polarization.…”

“…[67][68][69] Recently, self-powered perovskite photodetectors based on this principle have been demonstrated. [70][71][72][73][74][75] As an example, (EA)4Pb3Cl10 perovskite (where EA + is ethylammonium, or C2H5NH3 + ) semiconductor with a bandgap of 3.39 eV showed a spontaneous polarization (Ps of ∼4.5 μC cm -2 ) oriented along its crystallographic c-axis (Figure 8 A-C). 71 This enabled the construction of a visible-blind UVphotodetector which can operate at zero bias, using only the built-in field of the ferroelectric polarization.…”

Double Free: A Promising Route toward Moisture-Stable Hypotoxic Hybrid Perovskites

“…[1][2][3][4][5] These compounds exhibit promising application potential in photodetectors, solar cells and light-emitting diodes. [6][7][8][9][10][11][12][13][14] Their excellent performance is attributed to the physical properties of Pb-OHPs, including good optical absorption, moderate band gap, low exciton binding energy (E b ), and high carrier mobility.…”