Two-Dimensional Layered Perovskite Ferroelectric with Giant Piezoelectric Voltage Coefficient

Abstract

Piezoelectric sensors that can work under various conditions with superior performance are highly desirable with the arrival of the Internet of Things. For practical applications, a large piezoelectric voltage coefficient g and a high Curie temperature T c are critical to the performance of piezoelectric sensors. Here, we report a two-dimensional perovskite ferroelectric (4-aminotetrahydropyran)2PbBr4 [(ATHP)2PbBr4] with a saturated polarization of 5.6 μC cm–2, high T c of 503 K [above that of BaTiO3 (BTO, 393 K)], and extremely large g 33 of 660.3 × 10–3 V m N–1 [much beyond that of Pb­(Zr,Ti)­O3 (PZT) ceramics (20 to 40 × 10–3 V m N–1), more than 2 times higher than that of poly­(vinylidene fluoride) (PVDF, about 286.7 × 10–3 V m N–1)]. Combined with the advantages of molecular ferroelectrics, such as light weight, easy and environmentally friendly processing, and mechanical flexibility, (ATHP)2PbBr4 would be a competitive candidate for next-generation smart piezoelectric sensors in flexible devices, soft robotics, and biomedical devices.

Centimeter‐Sized Single Crystals of Two‐Dimensional Hybrid Iodide Double Perovskite (4,4‐Difluoropiperidinium)4AgBiI8 for High‐Temperature Ferroelectricity and Efficient X‐Ray Detection

“…[ 16 ] Optical gap band is 2.03 eV by fitting the Tauc‐equation at 303 K, and due to thermochromism, band gap decreases to 1.93 eV at 433 K (Inset of Figure 4b). [ 17 ] This band gap is significantly lower than recently those reported 2D lead halide perovskite ferroelectrics, such as (benzylammonium) 2 PbCl 4 (3.65 eV), [ 11b ] [2‐FBA] 2 PbCl 4 (3.62 eV), [ 10g ] (ATHP) 2 PbBr 4 (3.62 eV), [ 18 ] (EA) 2 (MA) 2 Pb 3 Br 10 (2.70eV), [ 6d ] (C 4 H 9 NH 3 ) 2 CsPb 2 Br 7 (2.70eV), [ 10c ] and (4,4‐difluorocyclohexylammonium) 2 PbI 4 (2.38 eV). [ 6h ]…”

Piezotronics in two‐dimensional materials

“…Organic–inorganic hybrid perovskites have developed into a new type of 2D piezotronic material 125–133 . The organic–inorganic hybrid perovskites have already made into monolayer 2D sheets in 2015 (Figure 4A,B).…”

Effective Piezo‐Phototronic Enhancement of Flexible Photodetectors Based on 2D Hybrid Perovskite Ferroelectric Single‐Crystalline Thin‐Films

“…As a result, the in‐plane ferroelectric domains exhibit a non‐180° domain wall, confirming the biaxial nature of EA 4 Pb 3 Br 10 . [ 38,39 ]…”

“…[ 18–23 ] Figure 3c shows the lateral piezoresponse as a function of the driving voltage, which is correlated with the contact resonant frequency at the range of 240–260 kHz. [ 39,46 ] The amplitude values are verified by calibrating the resonant amplitude with the quality factor. Figure 3d exhibits the linear trend of the lateral piezoresponse, accompanied by the increasing bias for both EA 4 Pb 3 Br 10 SCFs and poly(vinylidene fluoride) (PVDF) membrane.…”