3D Printing of Stiff Photonic Microparticles into Load-Bearing Structures

Area of Science:

• Materials Science
• Nanotechnology
• Optics

Background:

• Structural colors offer a sustainable alternative to pigments due to their brightness and durability.
• Conventional methods for producing structural colors face challenges in scalability and 3D fabrication due to defects and processing limitations.

Purpose of the Study:

• To develop a scalable and versatile method for fabricating complex 3D structures with tunable optical and mechanical properties using structural colors.
• To overcome the limitations of traditional colloidal self-assembly and material processing for large-scale structural color applications.

Main Methods:

• Formulating rigid photonic microparticles into an ink with soft microgels for 3D printing via direct ink writing (DIW) at room temperature.
• Creating a percolating hydrogel network that covalently links microgels to rigidify the granular structure and control mechanical properties.
• Investigating the influence of microgel composition and volume fraction on the mechanical characteristics of the photonic granular materials.

Main Results:

• Successfully 3D printed centimeter-sized macroscopic structures with locally varying mechanical and optical properties.
• Demonstrated the fabrication of intricate 3D objects, including a photonic butterfly and a temperature-responsive photonic material.
• Showcased the tunability of mechanical properties by adjusting the microgel content in the photonic granular material.

Conclusions:

• The DIW approach using photonic microparticle inks provides a scalable and adaptable platform for creating advanced structural color materials.
• This method enables the precise engineering of 3D photonic structures with tailored optical and mechanical responses for diverse applications.
• The developed technique offers a promising pathway for environmentally friendly, high-performance colorants and functional materials.