Large second harmonic generation in a penta-CdO₂sheet exfoliated from its bulk phase

Abstract

Two-dimensional (2D) materials composed solely of pentagonal motifs are of particular interest due to their unique geometries and novel properties. Especially, the broken centrosymmetry and in-plane mirror symmetry in penta-graphene-like...

Torsion Angles between Donor and Acceptor Moieties as a Descriptor for Designing Nonlinear Optics and Thermally Activated Delayed Fluorescence Materials

“…NLO/TADF materials take pivotal positions in the development of the advanced technologies of optical frequency conversion and organic light-emitting diodes (OLEDs), − respectively. Recent years have witnessed a growing interest in the design of high-performance NLO/TADF materials to meet the requirements of practical applications. − It is widely recognized that β plays a decisive role in the performance of NLO materials. Thus, as an effective strategy to increase β, the design of strong intramolecular charge transfer (ICT) molecules with twisted D–A architecture has emerged as a novel frontier in materials science. ,,,,− Actually, twisted D–A molecules are extensively utilized for constructing the high-performance TADF material as well. − ,− It is largely because of the fact that reasonable D–A architecture can help to separate the highest occupied molecular orbital from the lowest occupied molecular orbital, resulting in a lower Δ E ST .…”

Computational Investigation on Pentagonal Monolayer HgO2 with Ultrahigh Anisotropic Carrier Mobility and Low Gibbs Free Energy for Photocatalytic Water Splitting

“…Up to date, the studied pentagon-based 2D materials are mainly composed of carbides, nitrides, phosphides, and sulfides. In contrast, seldom attention has been paid to the pentagon-based 2D oxides and only pentagonal ZnO 2 and CdO 2 monolayer materials have been theoretically explored. − Penta-ZnO 2 is a candidate with great promise for transparent electrodes with very low reflectance, while penta-CdO 2 exhibits extraordinary second harmonic generation (SHG) responses with large static SHG susceptibilities. Inspired by these interesting properties of the pentagon-based 2D materials, we tried to search for more pentagon-based 2D oxides with the crystal prediction algorithm RG 2 based on space group theory and graph theory and further explore their electronic, optical, and photocatalytic properties.…”

Type-1 Pentagonal Tiling Realized in 2D Penta-SrP2 Sheet

“…It is recognized that novel properties are buried in the pentagon-based lattice of penta-graphene. , Currently over 130 pentagon-based two-dimensional (2D) materials have been theoretically designed, and some of them have been synthesized after the predictions, , including penta-PdSe 2 , , penta-PdS 2 , and penta-NiN 2 . These 2D sheets show intriguing properties and promising applications in auxetics, , nonlinear optics, , piezoelectricity, − thermal transport, − thermoelectricity, , photodetectors, photodiodes and gas sensors . It is interesting to notice that all of the pentagon-based 2D materials exclusively feature the type-2 and type-4 tiling patterns among the 15 known pentagonal tilings that tile the Euclidean plane with no gaps or overlaps by using identical copies of a pentagonal motif.…”