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Magnetically responsive colloidal crystals with angle-independent gradient structural colors in microfluidic droplet
Junjie Chi1, Changmin Shao2, Yalan Zhang3
1Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, Shenzhen University, Shenzhen 518060, China. ttkong@szu.edu.cn nidong@szu.edu.cn and State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China. yjzhao@seu.edu.cn.
Nanoscale
|June 29, 2019
Summary
We developed a method to create gradient structural color films using magnetically responsive colloidal nanoparticles. These films offer tunable optical properties for advanced optical devices.
Area of Science:
- Materials Science
- Nanotechnology
- Optics
Background:
- Colloidal crystal films exhibit structural colors, valuable for optical applications.
- Controlling these colors with external stimuli is crucial for advanced devices.
Purpose of the Study:
- To develop a practical method for fabricating colloidal crystal hydrogel films with continuous gradient structural colors.
- To utilize superparamagnetic colloidal nanoparticles for magnetically tunable structural colors.
Main Methods:
- Fabrication of colloidal crystal hydrogel films using superparamagnetic colloidal nanoparticles.
- Self-assembly of nanoparticles into chain-like arrays under external magnetic fields.
- Application of spatial magnetic fields with varying strength and direction to achieve gradient color changes.
Main Results:
- Demonstrated continuous gradient structural colors in colloidal crystal films.
- Achieved angle-independent gradient structural colors through integration with microfluidic templates.
- Successfully fabricated free-standing colloidal crystal films with tunable optical properties.
Conclusions:
- A practical method for fabricating magnetically responsive gradient structural color films was established.
- These films offer controllable optical properties via external magnetic stimuli.
- The developed films are suitable for fabricating advanced optical devices.
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