The Microrobots Cleaning Our Oceans

Ava Steiner '22 ~ September 2021

Microplastics are accumulating rapidly in the ocean. These plastics are under five-millimeter fragments of discarded clothing, packaging, and other synthetically produced items, and can disrupt sea creatures’ vital functions, like eating and reproducing. But a team of scientists in the Czech Republic have a solution to microplastic pollution: tiny, plastic-eating robots.

Chemist Martin Pumera at the Czech University of Chemistry and Technology has been working for almost a decade on developing miniscule robots that can propel themselves in water with a little hydrogen peroxide. Now, Pumera is hoping he and his team can use the robots to rid the ocean of plastic.

The star-shaped bots begin to move when they absorb light energy and hydrogen peroxide, then they grab hold of plastic and break chemical bonds in the plastic’s molecules, a process known as photocatalysis. A magnetic coating makes the robots easy to collect after use with a magnet. In the first test of four different plastic types, the robots were able to break down 0.5%-3.0% of the plastic weight-- not a lot, but a strong start that shows proof of concept.

These tiny robots have a while to go before they can be released in the ocean, however. Pumera’s team still has to find an alternative to hydrogen peroxide power. The scientists also want to set a limit on how deep the robots can swim so that they don’t become pollutants themselves. Other scientists worry that the microrobots would stick to substances other than plastic and cause more harm. Some environmentalists fear that any hope from this invention may lead to companies taking less responsibility for plastic production.

In the near future, Pumera hopes to implement the microrobots to help wastewater treatment plants. But for now, reducing plastic use and production is the first step in keeping our oceans clean.

Title Photo: sergeitokmakov, Pixabay