Pyrochlore Light-Emitting Ceramic Bi Doping Quantum Yield
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current light-emitting ceramics have limitations in achieving high quantum efficiency of emission, which is essential for efficient light emission when excited by light sources.
Innovation Solution
A light-emitting ceramic is developed by heat-treating a ceramic with a pyrochlore-type compound, where A includes elements like La, Gd, Yb, or Lu, B includes Bi and Zr, Sn, or Hf, and W is present for electrical neutrality, optimizing Bi content between 0.001 mol % to 5 mol % to enhance quantum yield and light transmittance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If conventional light-emitting ceramics are used, then the device can emit light, but the quantum efficiency is insufficient
Solution Approach 1:
The patent changes the chemical composition parameters of the ceramic by incorporating Bi at the B site in the pyrochlore structure (formula ABOw where B includes Bi and at least one element from Zr, Sn, Hf), and controls the heat treatment conditions (reducing atmosphere, specific temperature ranges). These parameter changes result in a ceramic with high quantum yield (40% or more) while maintaining structural stability and emission reliability.
Solution Approach 2:
The patent creates a composite ceramic material by combining multiple elements (A site elements from La, Y, Gd, Yb, Lu; B site elements including Bi, Zr, Sn, Hf) in a specific pyrochlore structure. This composite approach allows optimization of both quantum efficiency and structural reliability, achieving superior emission performance compared to conventional single-component phosphors.
2Illumination intensity
If the ceramic thickness is increased to improve light transmittance, then more light can pass through, but the device size increases
Solution Approach 1:
The patent changes the optical parameters of the ceramic material itself by optimizing its composition (Bi content at B site: 0.001-5 mol %) and crystal structure through heat treatment. This improves the intrinsic light transmittance property of the material, allowing thin ceramics (1 mm thickness specified) to achieve 50% or more light transmittance in the 450-800 nm range, thus maintaining compact size while ensuring adequate light transmission.
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
The ceramic achieves a high emission quantum yield of 40% or more and high light transmittance, enabling efficient light emission across a wide wavelength range, surpassing previous designs and allowing for the creation of high-efficiency light-emitting elements and devices.
Implementation Method 1
a light-emitting ceramic according to the present invention is formed by heat-treating, in a reducing atmosphere, a ceramic that contains, as a major component, a pyrochlore-type compound
Implementation Method 2
a light-emitting ceramic which emits light different in a wavelength from excitation light when the excitation light enters a light-emitting element
Data Source
AI summary
A light-emitting ceramic that contains, as a major component thereof, a pyrochlore compound represented by ABOw, wherein A includes at least one element selected from the group consisting of La, Y, Gd, Yb and Lu, B includes Bi and at least one element selected from the group consisting of Zr, Sn and Hf, and W is a positive number.