Core-Shell Electron Transport Particles for OLED Energy Barriers

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current light-emitting devices face challenges in enhancing electron transport efficiency and reducing surface defects, leading to limited luminescence and lifespan, particularly due to the energy barrier at the interface between the emission layer and the electron transport layer.

Innovation Solution

Incorporating an electron transport layer with electron transporting particles having a core, a first shell, and a second shell, where the shells are composed of oxide or chalcogenide compounds, which act as protective layers and reduce surface defects, thereby lowering the energy barrier for electron injection and increasing electron density in the emission layer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a conventional electron transport layer is used, then the device structure is simple, but the electron transport efficiency is low due to high energy barrier at the interface

Engineering Contradiction:

Improveelectron transport efficiencyVSAvoidparticle structure complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The electron transporting particle is segmented into multiple functional regions: a core region containing the electron transporting compound, and a shell region containing the oxide or chalcogenide material. This segmentation allows each region to perform its specific function - the core provides electron transport while the shell reduces surface defects and lowers the energy barrier at the interface with the emission layer.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The electron transporting particle is constructed as a composite material combining an electron transporting compound (in the core) with oxide or chalcogenide materials (in the shell). This composite structure leverages the electron transport properties of the first material and the surface defect reduction properties of the second material, achieving both high electron transport efficiency and low interfacial energy barrier.

Inventive Principle:

Principle #40Composite materials

2Illumination intensity

If the emission layer interface has high surface defects, then the material is simpler, but the luminescence efficiency is limited due to high energy barrier

Engineering Contradiction:

Improveluminescence efficiencyVSAvoidinterface quality

Core Design Contradiction:

Illumination intensityVSReliability

Solution Approach 1:

The shell region of the electron transporting particle, composed of oxide or chalcogenide materials, acts as an intermediary layer between the core and the emission layer. This intermediary shell reduces surface defects at the interface and lowers the energy barrier for electron injection into the emission layer, thereby improving luminescence efficiency without compromising interface quality.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Duration of action of stationary object

If electron injection barrier is high, then the device structure is simpler, but the electron density in emission layer is low limiting lifespan

Engineering Contradiction:

Improvedevice lifespanVSAvoidelectron injection energy barrier

Core Design Contradiction:

Duration of action of stationary objectVSUse of energy by moving object

Solution Approach 1:

The shell material (oxide or chalcogenide) changes the energy parameter at the interface by reducing surface defects and lowering the electron injection energy barrier. This parameter change enables more efficient electron injection into the emission layer, increasing electron density and thereby extending device lifespan through improved operational stability.

Inventive Principle:

Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This configuration improves the efficiency and lifespan of light-emitting devices by enhancing electron transport and reducing surface defects, resulting in increased luminescence efficiency and prolonged device performance.

Implementation Method 1

the electron transport layer includes an electron transporting particle

Methodology Applied

Scientific EffectElectron transport: Conduction (electrical)

Implementation Method 2

a first shell covering the core, and a second shell covering the first shell, the first shell includes a first compound, the second shell includes a second compound

Methodology Applied

Scientific EffectProtective layer effect: Coatings

Implementation Method 3

thereby lowering the energy barrier for electron injection and increasing electron density in the emission layer

Methodology Applied

Scientific EffectEnergy barrier reduction:

Data Source

PatentUS20230180504A1Light-emitting device and electronic apparatus including the same

Publication Date: 2023.06.08 SAMSUNG DISPLAY CO LTD

AI summary

A light-emitting device and an electronic apparatus including the light-emitting device. The light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an interlayer between the first electrode and the second electrode, wherein the interlayer may include an emission layer and an electron transport layer, the electron transport layer may be between the emission layer and the second electrode, the electron transport layer may include an electron transporting particle, the electron transporting particle may include a core, a first shell covering the core, and a second shell covering the first shell, the first shell may include a first compound, the second shell may include a second compound, the core may include a third compound, and the first compound and the second compound may each independently include an oxide, a chalcogenide, or any combination thereof.