scholarly journals Optical Performance and Moisture Stability Enhancement of Flexible Luminescent Films Based on Quantum-Dot/Epoxy Composite Particles

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2100
Author(s):  
Guanwei Liang ◽  
Yong Tang ◽  
Jiarui Huang ◽  
Jiasheng Li ◽  
Yikai Yuan ◽  
...  
Keyword(s):  
Epoxy Resin ◽  
Composite Particle ◽  
Composite Particles ◽  
Silicone Resin ◽  
Optical Performance ◽  
Ambient Conditions ◽  
High Moisture ◽  
Luminescent Films ◽  
Moisture Stability ◽  
Silicone Film

Quantum dots (QDs) have been widely applied in luminescent sources due to their strong optical characteristics. However, a moisture environment causes their quenching, leading to an inferior optical performance in commercial applications. In this study, based on the high moisture resistance of epoxy resin, a novel epoxy/QDs composite particle structure was proposed to solve this issue. Flexible luminescent films could be obtained by packaging composite particles in silicone resin, combining the hydrophobicity of epoxy resin and the flexibility of PDMS simultaneously. The photoluminescence and light extraction were improved due to the scattering properties of the structure of composite particles, which was caused by the refractive index mismatch between the epoxy and silicone resin. Compared to the QD/silicone film under similar lighting conditions, the proposed flexible film demonstrated increased light efficiency as well as high moisture stability. The results revealed that a light-emitting diode (LED) device using the composite particle flexible (CPF) structure obtained a 34.2% performance enhancement in luminous efficiency as well as a 32% improvement in color conversion efficiency compared to those of devices with QD/silicone film (QSF) structure. Furthermore, the CPF structure exhibited strong thermal and moisture stability against extreme ambient conditions of 85 °C and 85% relative humidity simultaneously. The normalized luminous flux degradation of devices embedded in CPF and QSF structures after aging for 118 h were ~20.2% and ~43.8%, respectively. The satisfactory performance of the CPF structure in terms of optical and moisture stability shows its great potential value in flexible commercial QD-based LED displays and lighting applications.

scholarly journals Effective Interactions of Relativistic Composite Particles in Unified Nonlinear Spinor-Field Models. I

1985 ◽  
Vol 40 (1) ◽  
pp. 14-28
Author(s):  
H. Stumpf
Keyword(s):  
Spinor Field ◽  
Bound States ◽  
Composite Particle ◽  
Composite Particles ◽  
Statistical Interpretation ◽  
Particle Spectrum ◽  
Nonlinear Spinor ◽  
Effective Interactions ◽  
Scattering States ◽  
Diagonal Part

Unified nonlinear spinor field models are selfregularizing quantum field theories in which all observable (elementary and non-elementary) particles are assumed to be bound states of fermionic preon fields. Due to their large masses the preons themselves are confined. In preceding papers a functional energy representation, the statistical interpretation and the dynamical equations were derived. In this paper the dynamics of composite particles is discussed. The composite particles are defined to be eigensolutions of the diagonal part of the energy representation. Corresponding calculations are in preparation, but in the present paper a suitable composite particle spectrum is assumed. It consists of preon-antipreon boson states and threepreon- fermion states with corresponding antifermions and contains bound states as well as preon scattering states. The state functional is expanded in terms of these composite particle states with inclusion of preon scattering states. The transformation of the functional energy representation of the spinor field into composite particle functional operators produces a hierarchy of effective interactions at the composite particle level, the leading terms of which are identical with the functional energy representation of a phenomenological boson-fermion coupling theory. This representation is valid as long as the processes are assumed to be below the energetic threshold for preon production or preon break-up reactions, respectively. From this it can be concluded that below the threshold the effective interactions of composite particles in a unified spinor field model lead to phenomenological coupling theories which depend in their properties on the bound state spectrum of the self-regularizing spinor theory.

Numerical Simulations of Electric Field Driven Self-Assembly of Monolayers of Mixtures of Nanoparticles

2017 ◽  
Author(s):  
E. Amah ◽  
N. Musunuri ◽  
Ian S. Fischer ◽  
Pushpendra Singh
Keyword(s):  
Electric Field ◽  
Physical Properties ◽  
Numerical Simulations ◽  
Self Assembly ◽  
Composite Particle ◽  
Critical Value ◽  
Direct Numerical Simulations ◽  
Composite Particles ◽  
Liquid Interfaces ◽  
Induced Dipole

We numerically study the process of self-assembly of particle mixtures on fluid-liquid interfaces when an electric field is applied in the direction normal to the interface. The force law for the dependence of the electric field induced dipole-dipole and capillary forces on the distance between the particles and their physical properties obtained in an earlier study by performing direct numerical simulations is used for conducting simulations. The inter-particle forces cause mixtures of nanoparticles to self-assemble into molecular-like hierarchical arrangements consisting of composite particles which are organized in a pattern. However, there is a critical electric intensity value below which particles move under the influence of Brownian forces and do not self-assemble. Above the critical value, when the particles sizes differed by a factor of two or more, the composite particle has a larger particle at its core and several smaller particles forming a ring around it. Approximately same sized particles, when their concentrations are approximately equal, form binary particles or chains (analogous to polymeric molecules) in which positively and negatively polarized particles alternate, but when their concentrations differ the particles whose concentration is larger form rings around the particles with smaller concentration.

Corrosion Resistant Coatings Based on Zinc Nanoparticles, Epoxy and Silicone Resins

2020 ◽  
Vol 20 (10) ◽  
pp. 6389-6395 ◽  
Author(s):  
Chuan-Chun Li ◽  
Tang-Yu Lai ◽  
Te-Hua Fang
Keyword(s):  
Electron Microscope ◽  
Epoxy Resin ◽  
Steel Substrate ◽  
Composite Coatings ◽  
Salt Spray ◽  
Nano Composites ◽  
Silicone Resin ◽  
Nano Composite ◽  
Corrosion Resistant ◽  
Zn Nanoparticles

In this study, corrosion-resistant composite coatings were produced by incorporating zinc (Zn) nanoparticles in an epoxy resin and a hybrid silicone resin. While performing sodium chloride saltspray tests, the corrosion performance of the nano-composite coatings was evaluated by applying these corrosion-resistant composite coatings on a carbon steel substrate. The nano-composite coatings on the substrates were characterized by an adhesion test, scanning electron microscope (SEM), and transmission electron microscope (TEM) with energy-dispersive X-ray spectroscopy (EDX). The results of the salt-spray tests showed that the Zn nanoparticles in the epoxy and hybrid silicone resins could react with permeated oxygen, thereby improving the anticorrosion properties of the Zn nano-composites. The corroded area of the epoxy resin samples decreased from more than 80% without Zn doping to less than 5% in a 3000-ppm Zn-doped sample after a 500-h saltspray test. An evaluation of the bactericidal properties showed that the Zn/epoxy and Zn/hybrid silicone resin nano-composites with at least 360 ppm of Zn nanoparticles exhibited bactericidal ability, which remarkably increased with the Zn nanoparticles content. The corrosion-resistant properties improved with the addition of Zn nano-composites coatings.

Hydrophobic 2D Perovskite‐Modified Layer with Polyfunctional Groups for Enhanced Performance and High Moisture Stability of Perovskite Solar Cells

Solar RRL ◽  
2020 ◽  
Vol 4 (12) ◽  
pp. 2000647
Author(s):  
Huifen Xu ◽  
Guozhen Liu ◽  
Xiaoxiao Xu ◽  
Shendong Xu ◽  
Liying Zhang ◽  
...  
Keyword(s):  
Solar Cells ◽  
Perovskite Solar Cells ◽  
High Moisture ◽  
Modified Layer ◽  
Moisture Stability

The investigation of methyl phenyl silicone resin/epoxy resin using epoxy-polysiloxane as compatibilizer

2014 ◽  
Vol 118 (1) ◽  
pp. 247-254 ◽  
Author(s):  
Qiang Liu ◽  
Xiao Bao ◽  
Shuangquan Deng ◽  
Xufu Cai
Keyword(s):  
Epoxy Resin ◽  
Silicone Resin ◽  
Methyl Phenyl

scholarly journals Preparation and properties studies of UV-curable silicone modified epoxy resin composite system

2018 ◽  
Vol 16 (1_suppl) ◽  
pp. 170-176 ◽  
Author(s):  
Zhouhui Yu ◽  
Aiyong Cui ◽  
Peizhong Zhao ◽  
Huakai Wei ◽  
Fangyou Hu
Keyword(s):  
Heat Resistance ◽  
Epoxy Resin ◽  
Resin Composite ◽  
Curing Kinetics ◽  
Resin Content ◽  
Silicone Resin ◽  
Two Phase ◽  
Uv Curable ◽  
Humidity Resistance ◽  
Modified Epoxy

Introduction: Modified epoxy suitable for ultraviolet (UV) curing is prepared by using organic silicon toughening. The curing kinetics of the composite are studied by dielectric analysis (DEA), and the two-phase compatibility of the composite is studied by scanning electron microscopy (SEM). Methods: The tensile properties, heat resistance, and humidity resistance of the cured product are explored by changing the composition ratio of the silicone and the epoxy resin. Results: SEM of silicone/epoxy resin shows that the degree of cross-linking of the composites decreases with an increase of silicone resin content. Differential thermal analysis indicates that the glass transition temperature and the thermal stability of the composites decrease gradually with an increase of silicone resin content. The thermal degradation rate in the high temperature region, however, first decreases and then increases. In general, after adding just 10%–15% of the silicone resin and exposing to light for 15 min, the composite can still achieve a better curing effect. Conclusions: Under such conditions, the heat resistance of the cured product decreases a little. The tensile strength is kept constant so that elongation at breakage is apparently improved. The change rate after immersion in distilled water at 60°C for seven days is small, which shows excellent humidity resistance.

Facile Synthesis of Flake Copper Powder Loaded With Silver Particles

2011 ◽  
Vol 109 ◽  
pp. 91-95
Author(s):  
Xiao Feng Tian ◽  
Wei Ke Zhang
Keyword(s):  
Copper Powder ◽  
Composite Particle ◽  
Copper Particle ◽  
Composite Particles ◽  
Silver Particles ◽  
Facile Synthesis ◽  
Wet Chemistry ◽  
Dispersing Agent ◽  
Copper Composite ◽  
Individual Particles

A fast and facile wet chemistry method has been developed for preparing monodispersed silver coated copper composite particles. Copper powder is coated using a solution containing [Ag (NH3)] +. The effect of the copper particle size distribution, the concentrations of [Ag (NH3)] + on composite particles conductivity were investigated. The composite particle with electric conductivity of 0.8×10-3 Ω•cm is obtained at 0.8 mol/L of Ag+ and1.0 g/L of dispersing agent. Copper powder loaded with silver particles morphologies range from individual particles to small islands, to the continuous multi-layers structure with Ag+ concentration increases.

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