(LiveScience) - Miniature robots hold great promise — tiny bots could help with tasks such as environmental cleanups in the future. But finding a way to power these tiny robotic helpers is a challenge because clean, lightweight and compact fuel sources are hard to develop.

Now, a team of engineers from the East China Normal University in Shanghai may have found a solution: They've developed a chemical motor for lightweight robots that can glide along the surface of a body of water. The findings are described in an October study published in the journal Langmuir.

The chemistry-based minimotor works because of a phenomenon called the Marangoni effect, which describes what happens when two liquids with strong surface tensions interact. The most famous example of the Marangoni effect is the so-called "legs" that run down the side of a glass of wine after the liquid in the cup is swirled. Because of this effect, liquids slip and slide alongside each other instead of mixing together.