Achieving circularly polarized luminescence and large piezoelectric response in hybrid rare-earth double perovskite by a chirality induction strategy

Abstract

A pair of 3D hybrid rare-earth double perovskites with large piezoelectric responses and CPL was constructed by introducing chirality. This study provides a strategy to prepare high-performance molecule-based piezoelectric and CPL materials.

Organic Single-Component Enantiomers with High Phase Transition Temperatures and Dielectric Switching Properties

“…The band structures of 1-R and 1-S were calculated according to DFT (Figure S7c–e), and the calculated E g was 5.668/5.658 eV. The experimental energy is relatively higher than the UV–visible absorption edge (5.406/5.504 eV), and this difference stems from the limitations of the DFT method. , Furthermore, we can assign energy bands according to the partial density of states (PDOS) . From the PDOS of 1-R and 1-S in Figure S7d,f, it can be seen that the energy bands at the top of the valence band (VB) originate from the C–P, N–P, and O–P states, whereas the energy band at the bottom of the conduction band (CB) originates from the unoccupied C–P orbital .…”

“…51,52 Furthermore, we can assign energy bands according to the partial density of states (PDOS). 53 From the PDOS of 1-R and 1-S in Figure S7d,f, it can be seen that the energy bands at the top of the valence band (VB) originate from the C−P, N−P, and O−P states, whereas the energy band at the bottom of the conduction band (CB) originates from the unoccupied C−P orbital. 44 Clearly, both the VB maxima and CB minima of 1-R and 1-S are the result of the π-electron-conjugated system.…”

Halogen Engineering To Realize Regulable Multipolar Axes, Nonlinear Optical Response, and Piezoelectricity in Plastic Ferroelectrics

“…Ferroelectrics can exhibit spontaneous polarization that can be reversed or reoriented under the application of an external electric field, among which multiaxial ferroelectrics are more practical because they are no longer confined to the single-crystal form. − The polarization axis in multiaxial ferroelectrics can be adjusted to several equivalent directions under the application of an external electric field, resulting from multiple equivalent axes in the paraelectric phase corresponding to the polarization axis in the ferroelectric phase. ,− …”

Switchable Dielectric Two-Dimensional Lead-Free Perovskite with Reversible Thermochromic Response

“…Organic–inorganic hybrid perovskites (OIHPs) have attracted widespread attention for wide applications in photovoltaic, photoelectronic, and photocatalytic fields, by taking advantage of their structural diversity, adjustable bandwidth, flexibility, low cost, light weight, and easy preparation. − In recent years, three-dimensional (3D) star materials have received remarkable interest and have seen rapid development in the area of solar cells, light-emitting diodes (LEDs), X-ray detectors, and shape-memory materials. , Compared with 3D structures, two-dimensional (2D) OIHPs have attracted increasing attention due to the properties of chemical diversity, broadband emission, quantum well structure, and layer-tunable optoelectronic characteristics. − The 2D OIHPs adopted layered structures of organic layers alternating with inorganic octahedral network layers connected by hydrogen bonds or other intermolecular forces. − These layered structural features provide great opportunities for phase transitions, which play a crucial role in phase-transition switches, shape-memory materials, and capacitors. For OIHPs, it is of vital significance to increase the phase-transition temperatures of molecular hybrid perovskites.…”