Spontaneous symmetry breaking enables anti-rolling motion of MnO2 microrods
Research output: Contribution to journal › Research article › Contributed › peer-review
Contributors
Abstract
Spontaneous symmetry breaking in colloidal systems increasingly fascinates scientists due to the promise of new, emergent functionalities and unique properties. Here, we introduce a chemically active system where symmetry is spontaneously broken in the particle motion rather than being encoded into their structure. Using symmetric MnO2 microrods without any apparent structural features or chirality, we observe the emergence of a combination of rotational and translational motion near a substrate that resembles rolling. This motion is further enhanced if a chemically active substrate is present. To explain the occurrence of highly active motion, we investigate the flows that lead to propulsion. The results are rationalized by a theoretical model showing spontaneous symmetry breaking with a bifurcation above a critical Péclet number. To identify the chemical reactions leading to the occurrence of flow, we confirm the species involved using electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS). Overall, the results demonstrate the potential of spontaneous symmetry breaking to accomplish active rolling motion of symmetric chemically active microparticles.
Details
| Original language | English |
|---|---|
| Article number | 100618 |
| Journal | Newton |
| Volume | 2 |
| Issue number | 8 |
| Publication status | Published - 3 Aug 2026 |
| Peer-reviewed | Yes |
Keywords
ASJC Scopus subject areas
Keywords
- anti-rolling, colloid, manganese oxide rod, spontaneous symmetry breaking