Electrocatalytic upcycling of plastic waste: Progress, challenges, and future

Abstract

The escalating accumulation of plastic waste has been developed into a formidable global environmental challenge. Traditional disposal methods such as landfilling and incineration not only exacerbate environmental degradation by releasing harmful chemicals and greenhouse gases, but also squander finite resources that could otherwise be recycled or repurposed. Upcycling is a kind of plastic recycling technology that converts plastic waste into high-value chemicals and helps to avoid resource waste and environmental pollution. Electrocatalytic upcycling emerges as a novel technology distinguished by its mild operational conditions, high transformation efficiency and product selectivity. This review commences with an overview of the recycling and upcycling technology employed in plastic waste management and the respective advantages and inherent limitations are also delineated. The different types of plastic waste upcycled by electrocatalytic strategy are then discussed and the plastic waste transformation process is examined together with the mechanisms underlying the electrocatalytic upcycling. Furthermore, the structure-activity relationships between electrocatalysts and plastic waste upcycling performance are also elucidated. The review aims to furnish readers with a comprehensive understanding of the electrocatalytic techniques for plastic waste upcycling and to provide a guidance for the design of electrocatalysts towards efficient plastic waste transformation.

Keywords

electrocatalysis / high-value chemicals / plastic waste / upcycling

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2024 The Author(s). Electron published by Harbin Institute of Technology and John Wiley & Sons Australia, Ltd.