Abstract
Colloidal particle-assembled photonic crystals offer sustainable alternatives to traditional structural color materials, but their commercial use is limited by low optical quality and slow fabrication. We demonstrate that embedding colloidal particles in suitable matrix materials and adjusting particle volume fraction can accelerate fabrication by 10^2 −10^6 times while maintaining high optical performance. Using common materials such as glycerol and honey, we show that uniform photonic crystals with sharp 90% reflectance peaks can rapidly form under oscillatory shear induced by hand-flapping or roll-to-roll processing at meter-per-second speeds. A single shear oscillation within 0.05−0.5 s produces highly ordered structures that typically require thousands of oscillations. We analyze the mechanisms governing efficient photonic crystal assembly and outline practical principles for scalable production.
Feng Gao
PhD
Junjun Qiu
PhD
Tong An
PhD
Xinyu Jiang
PhD
Qibin Zhao
Associate Professor
My research focuses on soft functional materials in which mesoscale structure controls optical and physical properties. I have worked extensively on colloidal and particle-assembled photonic materials, developing scalable processing methods to organize soft particulate systems into structurally coloured films and coatings. A central theme of my work is how external mechanical fields, such as shear, bending, stretching, and cyclic deformation, can drive microstructural ordering, lattice transitions, and structure-dependent optical responses. More broadly, I am interested in programmable soft photonic materials and functional coatings, where colloidal assembly, deformation processing, and soft-matter physics can be used to create adaptive optical, thermal, sensing, or mechanically encoded material functions.