Photocatalytic valorization of biomass and plastics: A critical review focusing on bond-selective activation

Abstract

The transition from a linear economy to a circular carbon economy urgently requires sustainable and efficient technologies for converting non-fossil biomass and waste plastics into fuels and high-value chemicals. Solar-driven photocatalytic technology has emerged as a promising strategy due to its mild reaction conditions and potential for selective transformation, which addresses the limitations of traditional recycling and conversion methods (e.g., high energy consumption, harsh conditions, and poor selectivity). However, current photocatalytic valorization systems still suffer from insufficient activity and selectivity, mainly due to the inability to precisely regulate reaction pathways. Considering that selective bond activation (especially C–H and C–C bond activation) is the key determinant, this review focuses on the photocatalytic valorization of biomass and plastics, classifies reaction pathways based on dominant bond selectivity, and mainly emphasizes the contrast between C–H and C–C bond activation. This classification approach overcomes the limitations of traditional substrate-based classification, providing new insights for the rational design of highly selective photocatalytic systems to realize the valorization of biomass and waste plastics.

Graphical abstract

Keywords

photocatalytic valorization / biomass conversion / waste plastics / selective activation / photocatalysts

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