China builds solar catalyst from battery waste to break down plastic

Researchers in China have developed an innovative solar-driven catalyst made from recycled lithium iron phosphate (LFP) batteries to break down polyethylene terephthalate (PET) plastic into valuable monomers. The catalyst, composed of iron oxide (Fe₂O₃) nanoparticles uniformly dispersed on recycled graphite from battery anodes, uses sunlight to generate localized heat that efficiently depolymerizes polyester chains. Under simulated sunlight, this photothermal catalyst achieved a PET conversion rate of 59 percent and a monomer (BHET) yield above 39 percent within an hour, outperforming standard thermal methods by over threefold in conversion and eightfold in yield. The catalyst also demonstrated excellent durability, maintaining over 90 percent efficiency after 15 reuse cycles. The team further validated the catalyst’s practical application by designing an outdoor solar reactor employing a Fresnel lens to concentrate sunlight, reaching temperatures above 190 °C. This setup achieved nearly complete PET conversion (99.8 percent) in just 30 minutes, recovering