The Polymer Society of Korea

Abstract

Self-propelling particles move autonomously by creating local gradients. A classic example is the camphor boat, or Marangoni surfer, which leverages the Marangoni effect for propulsion. The driving force is a surface tension gradient near the surfer, formed by releasing a substance that locally lowers the surface tension. A major challenge for Marangoni surfers is to miniaturize them while precisely controlling their direction of motion. Here, we use 3D-printing to design miniaturized surfers with programmed motion. A 3D-printed hole functions as a micro-engine, providing a fuel outlet to induce Marangoni propulsion. By strategically positioning these outlets, we demonstrate a variety of controlled motions, including linear, rotational, and precessional. Such self-propelling Marangoni surfers with controlled motions may hold promise for eco-friendly functions, such as microplastic capture.