Accurate data on microplastic occurrence in aquatic and terrestrial ecosystems are a basic requirement for microplastic risk assessment and management. Existing analysis techniques like Raman spectroscopy and Fourier transform infrared (FT-IR) spectroscopy imaging are still time-consuming and depend on laborious sample preparation. Therefore, we investigate the potential of time-resolved photoluminescence spectroscopy as an alternative technique to identify plastic materials, and, for the first time determine the photoluminescence lifetime of a series of polymers and several non-plastic samples typically found in a marine environment. The obtained photoluminescence lifetimes can be used to distinguish between plastic and natural materials. Furthermore, they allow us to identify distinct types of plastics. Therefore, the described approach has the potential to identify materials either as a stand-alone technique or for pre-characterization of sample materials for otherwise time-consuming analytical methods such as Raman spectroscopy or FT-IR spectroscopy.
Keywords: Microplastics; TRPL; environmental science; materials identification; photoluminescence spectroscopy; time-resolved photoluminescence.