A Unified View of Carbon Neutrality: Solar-Driven Selective Upcycling of Waste Plastics

Abstract

With the rapid development of plastic production and consumption globally, the amount of post-consumer plastic waste has reached levels that have posed environmental threats. Considering the substantial CO₂ emissions throughout the plastic lifecycle from material production to its disposal, photocatalysis is considered a promising strategy for effective plastic recycling and upcycling. It can upgrade plastics into value-added products under mild conditions using solar energy, realizing zero carbon emissions. In this paper, we explain the basics of photocatalytic plastic reformation and underscores plastic feedstock reformation pathways into high-value-added products, including both degradation into CO₂ followed by reformation and direct reformation into high-value-added products. Finally, the current applications of transforming plastic waste into fuels, chemicals, and carbon materials and the outlook on upcycling plastic waste by photocatalysis are presented, facilitating the realization of carbon neutrality and zero plastic waste.

Keywords

Photocatalysis / Photoreforming / Plastics upcycling / Carbon neutrality / Energy storage and conversion

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