The mechanism of photocatalytic biomass reforming for H 2 production is far from fully understood. This study uses functionalized graphene dots with Pt-cocatalyst to reform cellulose in an alkaline solution under 1 sun illumination. Reforming of cellulose is initiated with the peeling of its constituent D-glucose units, which subsequently transform into deprotonated isosaccharinic acid (C 6 ). Further degradation of C 6 into molecules C 5 -C 1 proceeds through successive alternation of C-eliminating hydrolysis and photocatalytic oxidation of C 6 derivatives. The C 6 -C 1 species are quantitatively identified using chromatography and mass spectroscopy. The end C-containing product is predominantly HCOO − rather than HCO 3 − (or CO 2 ). The photocatalytic oxidation is accompanied by the photocatalytic reduction of water to produce H 2 . This reforming steadily produced H 2 for 6 days with a negligible rate decay, accomplishing 35% of the theoretical ultimate value for the reforming of cellulose. This study elucidates the detailed mechanism in the photocatalytic reforming of cellulose.

The influences of chemical and electronic structures on the photophysical properties of polymeric carbon nitrides (PCNs) photocatalysts, which govern the microscopic mechanisms of the superior photocatalytic activity under visible-light irradiation, have been resolved in this work. Time-resolved photoluminescence and in situ electron paramagnetic resonance measurements indicate that the photoexcited electrons in the fractured PCNs swiftly transfer to the C2p-localized states where the trapped photoelectrons exhibit longer lifetime compared to those in the ordinary PCNs. Moreover, the structure deviation at the carbon (Cb) atoms around the bridging sites of heptazine ring units, where trapped photoelectrons are localized, has been determined in the fractured PCNs based on the 13C solid-state nuclear magnetic resonance spectra and the density functional theory calculations. Accordingly, the formation of fractured PCNs by breaking the in-plane hydrogen bonds at a high temperature is a promising strategy for the enhancement of photocatalytic activity.

Interfacial charge transfer from TiO2 nanoparticles to layered MoS2 surface active sites via RGO nanosheets by suppressing the recombination rate of electron–hole pairs for enhanced photocatalytic activity.