InP Core ZnSe Shell Nanoparticles Halogen Doping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
InP-based semiconductor nanoparticles with a core/shell structure face challenges in achieving high quantum yield, narrow full width at half maximum, and small Stokes shift, which are essential for emitting green light with a wavelength of 532 nm or less when excited by blue light, due to defect levels and large Stokes shift issues.
Innovation Solution
The introduction of an appropriate amount of halogen into the semiconductor nanoparticles, increasing the Se content in the shell layer, and setting the Zn and Se molar ratios within specific ranges in the shell layer addresses these issues, resulting in core/shell type semiconductor nanoparticles with high quantum yield, small full width at half maximum, and small Stokes shift, capable of emitting green light with a wavelength of 532 nm or less.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If InP-based semiconductor nanoparticles with core/shell structure are used, then the emission wavelength can be controlled, but the quantum yield is lower and Stokes shift is larger compared to Cd-based nanoparticles
Solution Approach 1:
The patent optimizes the molar ratios of shell materials (Zn: 11.00-50.00, Se: 7.00-25.00 relative to In) and introduces halogen elements (0.80-15.00 relative to In) to modify the nanoparticle structure. These parameter changes reduce defect levels in the InP-based core/shell nanoparticles, thereby decreasing Stokes shift and improving quantum yield while maintaining emission wavelength control
Solution Approach 2:
The patent creates a composite core/shell structure with InP-based core and ZnSe-based shell, further enhanced by halogen element incorporation. This composite structure combines the advantages of different materials: the InP core provides tunable emission wavelength while the ZnSe shell with halogen reduces defect levels, achieving both wavelength control and high quantum yield
2Measurement precision
If the shell layer composition is optimized to reduce Stokes shift, then the emission wavelength control improves, but the manufacturing complexity increases
Solution Approach 1:
The patent establishes specific molar ratio ranges for shell materials (Zn: 11.00-50.00, Se: 7.00-25.00 relative to In) and halogen content (0.80-15.00 relative to In). These defined parameter ranges provide clear manufacturing guidelines that balance Stokes shift reduction with manageable manufacturing complexity, avoiding overly complex composition control
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 approach enables the production of semiconductor nanoparticles with improved quantum yield, reduced full width at half maximum, and minimized Stokes shift, effectively achieving the desired green emission wavelength, thereby enhancing the performance of quantum dot devices.
Implementation Method 1
Excitons formed in the semiconductor particles by means such as photoexcitation and charge injection emit photons having energy corresponding to the band gap by recombination
Data Source
Figure 1(A)~2
Figure 3~4
AI summary
Provided are core/shell type semiconductor nanoparticles including: a core including In and P; and a shell having one or more layers. At least one layer of the shell is formed of ZnSe. The semiconductor nanoparticles further comprise halogen. In the semiconductor nanoparticles, a molar ratio of halogen to In in terms of atoms is 0.80 ~ 15.00. A difference between a peak wavelength of an emission spectrum when the semiconductor nanoparticles are excited at 450 nm and a peak wavelength of an absorption spectrum of the semiconductor nanoparticles is 23 nm or less. According to the present invention, core/shell type semiconductor nanoparticles that include the core including In and P and the shell formed of ZnSe, and have high quantum yield, a small full width at half maximum, and small Stokes shift can be provided.