Photocatalytic upcycling of poly(ethylene terephthalate) plastic to high-value chemicals

Much attention has been drawn to develop efficient poly(ethylene terephthalate) (PET) recycling methods. Reported here is the solar-driven PET recycling coupled with H 2 production with carbonized polymer dots-graphitic carbon nitride (CPDs-CN) as catalyst. PET plastic is a “greener” alternative feedstock where its hydrolytic monomer ethylene glycol is converted into high added-value chemicals, mainly including glycolic acid, glycolaldehyde and ethanol; meanwhile, H 2 is produced from water splitting. The monomer terephthalic acid yield reaches 304.7 ± 17.2 μmol, exceeding the value of the catalyst-free group nearly twofold. Increased H 2 production rate upon hybridization with CPDs is achieved (1034 ± 134 vs. 291 ± 35 μmol g –1 h –1 , respectively). The adopted strategy allows plastic waste to be used as a valuable feedstock for the sustainable production of value-added solar chemicals and solar fuels. • CPDs/g-C 3 N 4 photocatalysts were employed for solar-driven PET recycling coupled with H 2 production. • PET plastic waste was a feedstock to synthesize high added-value chemicals. • The yield of high purity TPA was nearly twice that of the control group. • The photocatalytic H 2 production activity of g-C 3 N 4 was increased upon hybridization with CPDs.