Breaking down BPA and similar pollutants with sunlight, nanoparticles and graphene

Nikhil R. Jana and Susanta Kumar Bhunia explain that the class of pollutants known as endocrine disruptors has been shown to either mimic or block hormones in animals, including humans. That interference can cause reproductive and other health problems. The compounds are used to make many household and industrial products, and have been detected in soil, water and even human breast milk. Scientists have been working on ways to harness sunlight to break down endocrine disruptors to make them less of a health threat. But the approaches so far only work with ultraviolet light, which at a mere 6 percent of sunlight, means these methods are not very efficient. Jana and Bhunia wanted to find a simple way to take advantage of visible light, which comprises 52 percent of sunlight.

For inspiration, the researchers turned to an already-developed graphene composite that uses visible light to degrade dyes. They tweaked the composite and loaded it with silver nanoparticles that serve as an antenna for visible light. When they tested it, the new material successfully degraded three different kinds of endocrine disruptors: phenol, BPA and atrazine. They conclude that their composite is a promising way to harness visible light to break down these potentially harmful compounds and other organic pollutants.