Our plastic waste problem is a large one, and it’s only getting larger. This is a huge environmental problem that requires some big picture thinking, but scientists are also exploring more subtle ways of chipping away at it and that includes turning plastic waste into sources of fuel. New research out of Singapore’s Nanyang Technological University (NTU) has thrown another interesting possibility into the mix, with scientists converting consumer plastic into a chemical used to to produce electricity in hydrogen fuel cells by exposing it to sunlight.
The key to the breakthrough was the introduction of a new kind of photocatalyst, which is a material that harnesses light energy to power chemical reactions. In search of new ways to convert plastic waste into useful chemicals, the NTU team turned to a type of affordable, biocompatible metal called vanadium. This commonly forms part of the steel and aluminum alloys used in cars and aircraft, but the scientists found it might play a role in plastics recycling, too.
By adding the vanadium-based catalyst to a solution containing consumer plastics, heating it to 85° C (185° F) and then exposing it all to artificial sunlight, the team was able to break down key bonds within the plastic in the space of six days. Breaking apart these carbon-carbon bonds typically involves high temperatures, which is energy-intensive, but by harnessing sunlight instead the scientists may have found a greener way forward.