Although artificial micromotors with unconventional shapes are emerging as a powerful tool in various applications, little research has been undertaken to clarify their propulsion mechanism, especially how the shape effect alters bubble dynamics and hydrodynamic flows. In this study, we fabricated two types of bowl-shaped investigate distinct due concave convex surfaces, by coating platinum (Pt...

One exciting implication of micromotors is that they can be powered by rectifying non-equilibrium thermal fluctuations or mechanical vibrations via the so-called Feynman-micromotor. An example of mechanical rectification is found in the batteryless wristwatch. The original concept was described in as early as 1912 by Smoluchowski and was later revisited in 1963 by Feynman, in the context of rec...

Micromotors have shown significant potential for diverse future applications. However, a poor understanding of the propelling mechanism hampers its further applications. In this study, an accurate mechanical model of the micromotor has been proposed by considering the geometric asymmetry and fluid viscosity based on hydrodynamic principles. The results obtained from the proposed model are in a ...

Self-propelled micromotor-based fluorescent "On-Off" detection of nerve agents is described. The motion-based assay utilizes Si/Pt Janus micromotors coated with fluoresceinamine toward real-time "on-the-fly" field detection of sarin and soman simulants.

Abstract Understanding and controlling the swimming direction of a synthetic nano‐ micromotor holds fundamental applied significance. Here, we focus on platinum‐containing Janus colloids that catalytically decompose H 2 O into , an archetypical model chemical micromotor. We discover platinum oxides (primarily PtO) are produced Pt films sputter‐coated in plasma, PtO reverses motor possibly by se...

We describe polysilicon micromotors with diffraction gratings fabricated on the polished surface of the polysilicon rotor for optical switching applications. The motors have rotor diameters of 0.5–2 mm with grating elements having periods of 1.80 and 3.86 mm. These microswitches have rise times of 300 ms and settling times of 500 ms when driven by a 65-V switching pulse. The diffractive nature ...

A sperm-driven micromotor is presented as a targeted drug delivery system, which is appealing to potentially treat diseases in the female reproductive tract. This system is demonstrated to be an efficient drug delivery vehicle by first loading a motile sperm cell with an anticancer drug (doxorubicin hydrochloride), guiding it magnetically, to an in vitro cultured tumor spheroid, and finally fre...