A multiscale cascade strategy for lignocellulosic biomass valorization: From pretreatment and enzymatic hydrolysis to photocatalytic upgrading.

Abstract

Biomass is the most abundant renewable carbon resource in nature, and its efficient conversion and utilization are of great significance for mitigating the energy crisis and achieving carbon neutrality. Photocatalytic technology offers a highly promising route for biomass valorization, owing to its mild reaction conditions and tunable redox capability. However, lignocellulosic biomass possesses a highly complex structure with different components, making it difficult to achieve efficient and selective conversion through direct photocatalytic oxidation, and even more challenging to couple with reductive reactions such as water splitting to produce H2. This review proposes a new perspective of achieving biomass valorization through a cascade process including pretreatment, enzymatic hydrolysis, and photocatalysis for the first time. First, focusing on biomass-derived monosaccharides, the influence of photocatalyst design and microenvironment regulation on product selectivity is systematically introduced, and the mechanisms underlying the coupling of monosaccharide conversion with hydrogen evolution or CO2 reduction are explored. On this basis, for biomass-derived polysaccharides, the synergistic mechanisms between polysaccharide hydrolases and photocatalysts are discussed in depth. Finally, targeting real lignocellulosic biomass, the effects of pretreatment on the biomass structural modification and the consequent influence on enzymatic hydrolysis and photocatalytic conversion are analyzed. This review is expected to provide guidance for the efficient and high-value utilization of lignocellulosic biomass.

Abstract as supplied by the indexing source. © the authors / publisher.