Design and characterization of randomly speckled spheres

Area of Science:

• Materials Science
• Nanotechnology
• Surface Chemistry

Background:

• Fabricating particles with specific surface features is crucial for advanced materials.
• Controlling the size and distribution of surface modifications on microspheres presents a significant challenge.

Purpose of the Study:

• To introduce and demonstrate a novel particle lithography technique for creating randomly speckled spheres.
• To investigate the predictability and controllability of speckle formation on microspheres.

Main Methods:

• Utilized positively charged polystyrene microspheres (3.3 µm) as core particles.
• Employed negatively charged silica particles (0.9 µm) as masks and polystyrene nanoparticles (60 nm) for speckle formation.
• Removed masking particles to reveal patterned surfaces.

Main Results:

• Demonstrated reliable and predictable circular speckle diameters on core particles, aligning with geometric estimations.
• Showcased the ability to control the number of speckles by adjusting silica mask concentration.
• Confirmed results using electron microscopy and confocal microscopy.

Conclusions:

• Particle lithography offers a versatile method for creating patterned core-shell particles.
• The technique is adaptable to various materials, enabling applications requiring specific surface chemistries.
• This method is suitable for applications where precise patch placement is not critical.