Visible light-activated polyphenol-Al³⁺ coordination for ambient and quantitative xylose-to-furfural conversion

Bio-based xylose-to-furfural conversion is often accompanied by condensation/degradation at evaluated thermal conditions. This study presents a combined strategy of visible light-enhanced acidity and local photothermal effect for room-temperature cascade isomerization-dehydration of xylose to furfural in an ultrahigh yield (96.3%), in which Lewis acidic Al³⁺ centers facilitate electron transfer from xylose to initiate isomerization and the formation of Al³⁺-polyphenol complex is enabled to release Brønsted acid for dehydration while co-added bio-graphene in situ offers satisfactory photothermal conditions.