Precise surface patches on active particles of arbitrary shape through microstenciling.

Area of Science:

• Materials Science
• Micro- and Nanotechnology
• Physics

Background:

• Active particles harness environmental energy for programmable motion and collective behaviors.
• Particle shape and surface modifications advance applications in microrobotics and biomedicine.
• Conventional fabrication methods limit the precise creation of arbitrary active particles.

Purpose of the Study:

• To introduce a high-resolution microstenciling fabrication technique for arbitrary active particles.
• To overcome limitations in creating active particles with precise shapes and surface compositions.

Main Methods:

• Combines two-photon lithography with sacrificial stencil masking.
• Enables deposition of arbitrary metallic patches onto particles of any shape.
• Achieves a resolution limit as low as 0.2 micrometers.

Main Results:

• Demonstrated three types of active particles with nonconventional dynamics.
• Created electrokinetic active spheres with tunable 3D motions.
• Fabricated catalytic microdiscs exhibiting chiral axial spinning and steric magnetic particles forming self-limiting microrobots.

Conclusions:

• The high-resolution microstenciling technique is a versatile strategy for fabricating well-defined active particles.
• This method facilitates the creation of advanced active particles and microrobots.
• Enables diverse practical applications in microrobotics, biomedicine, and beyond.