Photon Up-Conversion Film With Liquid-Crystal Diffusion Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing photon up-conversion technologies in a solid state suffer from inefficient molecular diffusion, limiting their practical application in fields such as solar cells and photocatalysts due to insufficient up-conversion emission efficiency.
Innovation Solution
A photon up-conversion film comprising a color-forming portion with a sensitizing component and a light-emitting component, dispersed in a matrix, utilizing a medium with specific solvent and resin properties to enhance molecular diffusion and energy transfer, achieving a relaxation time of less than 210 ms.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If up-conversion emission is achieved in a solid state, then practical application is enabled, but molecular diffusion is suppressed and up-conversion efficiency becomes insufficient
Solution Approach 1:
The patent changes the physical state parameter of the medium from solid to liquid by introducing a liquid crystal compound. This parameter change enables molecular diffusion in the liquid crystal phase, allowing efficient triplet-triplet annihilation and high up-conversion emission efficiency, while maintaining practical solid-state film form application through controlled solidification.
2Reliability
If a resin film containing donor and acceptor compounds is used, then solid state up-conversion is achieved, but up-conversion emission efficiency remains insufficient
Solution Approach 1:
The patent creates a composite material system combining liquid crystal compounds with donor and acceptor compounds. The liquid crystal matrix provides both the fluidity needed for molecular diffusion and energy exchange, and the structural framework for solid-state film formation. This composite approach resolves the contradiction between solid-state stability and up-conversion efficiency.
3Productivity
If molecular diffusion is enhanced for efficient TTA, then up-conversion efficiency improves, but solid state structure is compromised
Solution Approach 1:
The patent introduces dynamic behavior into the solid-state film by using liquid crystal compounds that can transition between liquid and solid phases. In the liquid crystal phase, molecules exhibit dynamic diffusion necessary for efficient TTA, while the material can be controlled to solidify into a stable film structure for practical application, thus resolving the contradiction between dynamics and structural stability.
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 solution enables high-efficiency up-conversion with improved transmittance and emission efficiency by optimizing the medium, allowing for stable energy exchange and reduced energy loss.
Implementation Method 1
The sensitizing component is capable of absorbing light in a first wavelength region λ1
Implementation Method 2
The light-emitting component is capable of radiating light in a second wavelength region λ2 including wavelengths shorter than those of the first wavelength region λ1
Implementation Method 3
A technology including utilizing triplet-triplet annihilation (TTA) caused by collision between molecules in a triplet state has been known as up-conversion emission in an organic material
Implementation Method 4
In solution-based up-conversion in which a donor compound and an acceptor compound are dissolved in a solvent out of the kinds of up-conversion each utilizing the TTA (TTA-UC), energy exchange is efficiently performed by the diffusion of a molecule of the donor compound and a molecule of the acceptor compound
Data Source
AI summary
Provided are a photon up-conversion film, a photon up-conversion body, a laminate, and an energy conversion device, which are capable of high-efficiency up-conversion, and methods of producing the same. The photon up-conversion film according to an embodiment of the present invention includes a color-forming portion containing at least: a sensitizing component capable of absorbing light in a first wavelength region λ1; and a light-emitting component capable of radiating light in a second wavelength region λ2 including wavelengths shorter than those of the first wavelength region λ1. A relaxation time of the photon up-conversion film measured by a spin-echo method through use of time-domain nuclear magnetic resonance (pulse NMR) at 298 K is less than 210 ms.