Fabrication of Spherical Colloidal Supraparticles via Membrane Emulsification

Area of Science:

• Materials Science and Engineering
• Colloid and Interface Science
• Nanotechnology and Nanomaterials

Background:

• Colloidal supraparticles are micrometer-scale assemblies with diverse applications in photonics, catalysis, gas adsorption, and drug delivery.
• Efficient synthesis of supraparticles with narrow size distribution and high yield is crucial for their practical implementation.

Purpose of the Study:

• To demonstrate membrane emulsification as a high-throughput method for fabricating spherical colloidal supraparticles.
• To achieve control over supraparticle size, size distribution, and crystallinity.
• To investigate key process parameters influencing supraparticle properties and production.

Main Methods:

• Utilized membrane emulsification with a Shirasu porous glass membrane to generate emulsion droplets of aqueous colloidal dispersions in fluorocarbon oil.
• Consolidated particles within emulsion droplets via water removal to form spherical supraparticles.
• Systematically investigated the effects of particle dispersion flow rate, particle concentration, and membrane pore diameter.

Main Results:

• Successfully fabricated spherical supraparticles with narrow size distribution and well-ordered surface structures.
• Identified key process parameters controlling supraparticle size, distribution, and crystallinity.
• Achieved high production yields (tens of grams per day) with controlled supraparticle characteristics.

Conclusions:

• Membrane emulsification is a simple, versatile, and high-throughput method for producing high-quality colloidal supraparticles.
• This technique offers advantages over traditional methods, including control over particle properties and compatibility with nonfluorinated oils.
• Membrane emulsification bridges the gap between high-precision microfluidic techniques and high-throughput, less controlled methods.