Self-assembly, fluid dynamics, nanotechnology, nanofabrication, programable matter, emergent phenomena, computational methods for assembly prediction
Bubbles formed from microbial systems, such as bacteria and algae, play an important role in microorganisms’ dynamics and interactions. However, the complexity of these biological systems makes it difficult to model and understand how bubbles form, grow, and affect their environment. Spherical microparticles with both iron and platinum caps, which allow the particles to magnetically assemble and catalytically decompose hydrogen peroxide to swim, can serve as simple models for bubble-generating systems. Here, quasi-two-dimensional systems of these particles, known as magnetic Janus particle microswimmers, were studied in open-air cells with varying concentrations of hydrogen peroxide fuel and liquid film thicknesses. Film thickness was shown to impact bubble size, and therefore cluster morphology, as evidenced by tracking how particles aggregate and bubbles nucleate and grow. These results provide insight into bubble-driven self-assembly mechanisms, with implications for both synthetic and biological systems.