Plasmon enhanced glucose photoreforming for arabinose and gas fuel co-production over 3DOM TiO₂-Au

Glucose photoreforming provides a promising alternative strategy for biomass valorization. However, the use of harsh environment (high alkalinity or organic solvents) and low product selectivity due to non-selective free radical oxidative cleavage limit their application in large-scale settings. Here, we show photoreforming of glucose to arabinose with high selectivity in water using gold nanoparticles decorated three dimensionally ordered macroporous TiO₂ (3DOM TiO₂-Au). We demonstrate that the hierarchically porous 3DOM architecture and Au nanoparticles enhance glucose conversion and arabinose selectivity by improving glucose-photocatalysts interaction, electron generation, charge separation, and localized surface plasmon resonance (LSPR) induced light absorption. The 3DOM TiO₂-Au produces arabinose via the direct C1-C2 α-scissions mechanism as evidenced by ¹³C labeled glucose at C1 position. Our experimental results demonstrate the presence of Au(I) is crucial for glucose to arabinose selective conversion. Aside from arabinose production, 3DOM TiO₂-Au also generates considerable amount of gas fuels (H₂, CH₄ and CO) from transient dehydration and hydrogenation reaction of the by-product formic acid. The present work demonstrates a green and promising approach to convert biomass derived feedstocks into value-added chemicals along with gas fuel production.