scholarly journals Crystalization-enhanced Stability by Effectively Suppressing Pho-tooxidation Defect for Lasing Emission and Electroluminescent Device

2021 ◽  
Author(s):  
He Zhang ◽  
Dongqing Lin ◽  
Huifang Liu ◽  
Wei Liu ◽  
Yang-Cheng Wang ◽  
...  
Keyword(s):  
Blue Emission ◽  
Optoelectronic Device ◽  
Wide Bandgap ◽  
The Self ◽  
Color Purity ◽  
Deep Blue ◽  
Self Assembled ◽  
Bandgap Semiconductors ◽  
On The Road ◽  
Enhanced Stability

Abstract Effectively protection against photooxidation of wide bandgap semiconductors remains a challenge that become the bottleneck on the road to commercialization. Herein, we demonstrated the crystallization effects of fluorene-based blue emitters on long-wavelength green band (g-band) defect with the well-defined organic micro/nanocrystals obtained via the self-assembly of surfactant-assisted reprecipitation methods. For the key molecule model 2,2'-bi(9,9-dipropyl)fluorene (DDC3F), the self-assembled nanorods film ex-hibits an ultrastable spectral stability without the presence of g-band emission (530 nm), and even main-tains the deep-blue emission under ultraviolet exposure (~ 3 h). In contrast, the spin-coated amorphous film shows a poor color purity with a green-index of ~ 4. Our results offer a robust evidence on the princi-ple in aggregate-enhanced stability, which is severely ignored by the general application of amorphously glassy molecules in OLED devices. In addition, the single nanorod as Fabry-Pérot (FP) optical resonator exhibits size-dependent dual wavelength lasing at 392 nm (threshold: 102 mW/cm2) and 412 nm (threshold: 216 mW/cm2), and generates the deep-blue electroluminescence in solution-processing OLED devices. The supramolecular self-assembled micro/nanocrystals strategy provides a potential platform to maintain ultrastable color purity in wide-bandgap optoelectronic device.

Efficient non-doped fluorescent OLEDs with nearly 6% external quantum efficiency and deep-blue emission approaching the blue standard enabled by quaterphenyl-based emitters

2018 ◽  
Vol 6 (16) ◽  
pp. 4479-4484 ◽  
Author(s):  
Weixuan Zeng ◽  
Yongbiao Zhao ◽  
Weimin Ning ◽  
Shaolong Gong ◽  
Zece Zhu ◽  
...  
Keyword(s):  
Quantum Efficiency ◽  
External Quantum Efficiency ◽  
Blue Emission ◽  
Device Performance ◽  
Color Purity ◽  
Deep Blue ◽  
Blue Emitters ◽  
Excellent Color

Two quaterphenyl derivatives are rationally designed and synthesized as deep-blue emitters to simultaneously afford outstanding device performance and excellent color purity approaching the NTSC blue standard.

scholarly journals Self-assembled guanine ribbons as wide-bandgap semiconductors

2002 ◽  
Vol 13 (2-4) ◽  
pp. 1236-1239 ◽  
Author(s):  
A. Calzolari ◽  
R. Di Felice ◽  
E. Molinari ◽  
A. Garbesi
Keyword(s):  
Wide Bandgap ◽  
Wide Bandgap Semiconductors ◽  
Self Assembled ◽  
Bandgap Semiconductors

scholarly journals Electron Beam Induced Impurity Electro-Migration in Unintentionally Doped GaN

1999 ◽  
Vol 4 (S1) ◽  
pp. 257-262
Author(s):  
M. Toth ◽  
K. Fleischer ◽  
M. R. Phillips
Keyword(s):  
Electron Beam ◽  
Blue Emission ◽  
Wide Bandgap ◽  
Yellow Luminescence ◽  
Acceptor Pair ◽  
X Ray ◽  
Donor Acceptor ◽  
Bandgap Semiconductors ◽  
Si Content ◽  
Stationary Electron

Electron beam induced electromigration of ON+and H+impurities in unintentionally n-doped GaN was investigated using cathodoluminescence (CL) kinetics profiling, CL imaging of regions pre-irradiated with a stationary electron beam, and wavelength dispersive x-ray spectrometry (WDS). The presented results (i) illustrate induced impurity diffusion in wide bandgap semiconductors, (ii) provide experimental evidence for the (VGa−ON)2−model of yellow luminescence in GaN with low Si content1, (iii) confirm the roles of O in frequently reported bound exciton and donor-acceptor pair emissions and (iv) suggest the involvement of ON+and hydrogenated gallium vacancies in a blue emission in autodoped GaN.

Electron Beam Induced Impurity Electro-Migration in Unintentionally Doped GaN

1998 ◽  
Vol 537 ◽  
Author(s):  
M. Toth ◽  
K. Fleischer ◽  
M. R. Phillips
Keyword(s):  
Electron Beam ◽  
Blue Emission ◽  
Wide Bandgap ◽  
Yellow Luminescence ◽  
Acceptor Pair ◽  
X Ray ◽  
Donor Acceptor ◽  
Bandgap Semiconductors ◽  
Si Content ◽  
Stationary Electron

AbstractElectron beam induced electromigration of ON+ and H+ impurities in unintentionally n-doped GaN was investigated using cathodoluminescence (CL) kinetics profiling, CL imaging of regions pre-irradiated with a stationary electron beam, and wavelength dispersive x-ray spectrometry (WDS). The presented results (i) illustrate induced impurity diffusion in wide bandgap semiconductors, (ii) provide experimental evidence for the (VGa-ON)2- model of yellow luminescence in GaN with low Si content (ii) confirm the roles of 0 in frequently reported bound exciton and donor-acceptor pair emissions and (iv) suggest the involvement of ON+ and hydrogenated gallium vacancies in a blue emission in autodoped GaN.

scholarly journals Stereoisomer-Independent Stable Blue Emission in Axial Chiral Difluorenol

2021 ◽  
Vol 9 ◽  
Author(s):  
Mengna Yu ◽  
Xiong Jia ◽  
Dongqing Lin ◽  
Xue Du ◽  
Dong Jin ◽  
...  
Keyword(s):  
Blue Emission ◽  
Green Emission ◽  
Wide Bandgap ◽  
Promising Candidate ◽  
Wide Bandgap Semiconductors ◽  
Conjugated Molecules ◽  
Optical Stability ◽  
Photophysical Behavior ◽  
Bandgap Semiconductors ◽  
Organic Photonics

Bulky conjugated molecules with high stability are the prerequisite for the overall improvement of performance in wide-bandgap semiconductors. Herein, a chiral difluorenol, 2,2′-(9,9′-spirobi[fluorene]-2,2′-diyl)bis(9-(4-(octyloxy)phenyl)-9H-fluoren-9-ol) (DOHSBF), is set as a desirable model to reveal the stereoisomeric effects of wide-bandgap molecules toward controlling photophysical behavior and improving thermal and optical stability. Three diastereomers are obtained and elucidated by NMR spectra. Interestingly, the effect of modifying the stereo-centers is not observed on optical properties in solutions, pristine films, or post-treated film states. All three diastereomers as well as the mixture exhibit excellent spectral stability without undesirable green emission. Therefore, this stereoisomer-independent blue-emitting difluorenol will be a promising candidate for next-generation wide-bandgap semiconductors that would have extensive application in organic photonics.

Self-assembled energetic 3D metal–organic framework [Na8(N5)8(H2O)3]n based on cyclo-N5–

2018 ◽  
Vol 47 (5) ◽  
pp. 1398-1401 ◽  
Author(s):  
Yuangang Xu ◽  
Pengcheng Wang ◽  
Qiuhan Lin ◽  
Xuefeng Mei ◽  
Ming Lu
Keyword(s):  
Self Assembly ◽  
Metal Organic Framework ◽  
The Self ◽  
Metal Organic ◽  
Self Assembled ◽  
Enhanced Stability ◽  
Organic Framework

A new 3D zeolite-like MOF [Na8(N5)8(H2O)3]n with an enhanced stability has been successfully synthesized by the self-assembly of Na+ with cyclo-N5− ligands.

Nanoscale Self-Assembly Using Ion and Electron Beam Techniques: A Rapid Review

MRS Advances ◽  
2020 ◽  
Vol 5 (64) ◽  
pp. 3507-3520
Author(s):  
Chunhui Dai ◽  
Kriti Agarwal ◽  
Jeong-Hyun Cho
Keyword(s):  
Electron Beam ◽  
Self Assembly ◽  
Ion Beam ◽  
Three Dimensional ◽  
The Self ◽  
Stress Generation ◽  
Rapid Review ◽  
High Yield ◽  
3D Nanostructures ◽  
Self Assembled

AbstractNanoscale self-assembly, as a technique to transform two-dimensional (2D) planar patterns into three-dimensional (3D) nanoscale architectures, has achieved tremendous success in the past decade. However, an assembly process at nanoscale is easily affected by small unavoidable variations in sample conditions and reaction environment, resulting in a low yield. Recently, in-situ monitored self-assembly based on ion and electron irradiation has stood out as a promising candidate to overcome this limitation. The usage of ion and electron beam allows stress generation and real-time observation simultaneously, which significantly enhances the controllability of self-assembly. This enables the realization of various complex 3D nanostructures with a high yield. The additional dimension of the self-assembled 3D nanostructures opens the possibility to explore novel properties that cannot be demonstrated in 2D planar patterns. Here, we present a rapid review on the recent achievements and challenges in nanoscale self-assembly using electron and ion beam techniques, followed by a discussion of the novel optical properties achieved in the self-assembled 3D nanostructures.

scholarly journals Self-Assembly of Shape-Tunable Oblate Colloidal Particles into Orientationally Ordered Crystals, Glassy Crystals and Plastic Crystals

Soft Matter ◽  
2021 ◽  
Author(s):  
Jiawei Lu ◽  
Xiangyu Bu ◽  
Xinghua Zhang ◽  
Bing Liu
Keyword(s):  
Crystal Structures ◽  
Self Assembly ◽  
Colloidal Particles ◽  
Building Blocks ◽  
Fundamental Question ◽  
The Self ◽  
Plastic Crystals ◽  
Self Assembled ◽  
Glassy Crystals ◽  
The Relationship

The shapes of colloidal particles are crucial to the self-assembled superstructures. Understanding the relationship between the shapes of building blocks and the resulting crystal structures is an important fundamental question....

Sign in / Sign up

Export Citation Format

Share Document