Frustrated Lewis Pairs Enable Efficient Polyethylene Oxidative Upcycling.

Abstract

Catalytic oxidative upcycling of waste polyethylene (PE) into value-added dicarboxylic acids under mild conditions is highly attractive, yet the efficient activation of molecular oxygen remains a fundamental challenge. Herein, we report a catalyst microenvironment engineering strategy that introduces frustrated Lewis pairs (FLP) characteristics into established high-performance catalysts for unlocking their full catalytic potential, rather than relying on the development of entirely new catalytic materials. Using a Co-based catalyst as an example, we demonstrated that the designed FLP-CoOx catalyst, featuring abundant surface FLP sites, markedly enhances O2 activation, enabling the efficient generation of superoxide radicals (O2 •-) via a single-electron reduction pathway. As a result, an outstanding dicarboxylic acid carbon yield of up to 86.0% was achieved under mild conditions, representing a fourfold improvement over the conventional catalyst. Moreover, the catalytic system exhibited excellent performance toward the oxidative valorization of various real-world waste plastics. This work presents FLP-mediated catalyst microenvironment engineering as a general strategy for substantially enhancing the performance of existing catalysts, providing new opportunities for the oxidative upcycling of waste plastics.