Ternary ZnCdS quantum dots enable efficient photocatalytic oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran

Solid-solution Zn 0.2 Cd 0.8 S QDs balance redox ability, band alignment, and stability. • The QDs affords 95.4% HMF conversion and 70.1% DFF yield under visible light. • Synergisticeffects of h + , •O 2 − , and 1 O 2 drive highly selective HMF oxidation to DFF. The selective photocatalytic oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) into high-value platform chemicals represents a promising pathway toward achieving carbon neutrality and sustainable development. To overcome the limited visible-light response and severe photocorrosion of monometallic sulfide quantum dots (QDs), solid-solution ZnCdS QDs were fabricated, enabling efficient photocatalytic oxidation of HMF to high-value 2,5-Diformylfuran (DFF). Systematic characterizations reveal that the ternary ZnCdS QDs achieve an ideal balance between robust redox capability and favorable band alignment, alongside remarkable structural stability and sustainable recyclability. Under optimal conditions, the Zn 0.2 Cd 0.8 S QDs achieved 95.4 ± 0.3% HMF conversion and 70.1 ± 0.9% DFF yield. The reaction mechanism was elucidated via radical trapping experiments and electron paramagnetic resonance (EPR) measurements, demonstrating that reactive species, including h + , •O 2 − , and 1 O 2 synergistically promoted the high-value conversion of HMF to DFF. Download: Download high-res image (196KB) Download: Download full-size image