Sustainable Conversion of Microplastics to Methane with Ultrahigh Selectivity by a Biotic-Abiotic Hybrid Photocatalytic System

Angew Chem Int Ed Engl. 2022 Dec 23;61(52):e202213244. doi: 10.1002/anie.202213244. Epub 2022 Nov 24.

Abstract

Efficient conversion of microplastics into fuels provides a promising strategy to alleviate environmental pollution and the energy crisis. However, the conventional processes are challenged by low product selectivity and potential secondary pollution. Herein, a biotic-abiotic photocatalytic system is designed by assembling Methanosarcina barkeri (M. b) and carbon dot-functionalized polymeric carbon nitrides (CDPCN), by which biodegradable microplastics-poly(lactic acid) after heat pretreatment can be converted into CH4 for five successive 24-day cycles with nearly 100 % CH4 selectivity by the assistance of additional CO2 . Mechanistic analyses showed that both photooxidation and photoreduction methanogenesis worked simultaneously via the fully utilizing photogenerated holes and electrons without chemical sacrificial quenchers. Further research validated the real-world applicability of M. b-CDPCN for non-biodegradable microplastic-to-CH4 conversion, offering a new avenue for engineering the plastic reuse.

Keywords: Biosynthesis; Biotic-Abiotic Hybrids; Microplastics Conversion; Photocatalysis; Product Selectivity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbon
  • Methane*
  • Methanosarcina barkeri
  • Microplastics*
  • Plastics

Substances

  • Methane
  • Microplastics
  • Plastics
  • Carbon