Research progress on photothermal catalytic conversion of waste plastics

Abstract

Photothermal catalysis, as an efficient recycling technology for waste plastics, can convert waste plastics into high value-added chemicals, which is an important way to achieve sustainable recycling of plastics. Both traditional catalytic pyrolysis and photocatalytic technologies have inherent defects, while photothermal catalysis technology effectively makes up for the shortcomings of a single technology by synergistic light-heat integration, thus elevating plastic conversion efficiency and selectivity. In this paper, we systematically introduce the latest progress in the photothermal catalytic conversion of waste plastics on various catalysts (semiconductors, metal nanoions, carbon materials and composite catalysts) to prepare chemicals, focusing on the effects of different catalysts and reaction devices on the photothermal catalytic process and product distribution. In addition, the reaction mechanisms involved in photothermal catalysis such as non-radiative relaxation in semiconductors, thermal vibration of molecules, and local heating of plasma are systematically discussed. Based on the current research progress, this paper further points out the key scientific problems and technical challenges faced by this technology in the application of plastic recycling, and provides an important reference for the development of efficient recycling technology of waste plastics.