Solar-driven transient Lewis acid sites for synergistic efficient photocatalytic isomerization of glyceraldehyde

Lewis acid sites (LASs) are essential for the photocatalytic isomerization of biomass into high-value platform compounds. However, transient changes in the number of LASs in a photocatalytic system have not been clearly documented, often resulting in an inaccurate understanding of their role in isomerization. To address this challenge, in this study, the molecular probes glyceraldehyde was isomerized to 1,3-dihydroxyacetone (DHA, 63.5 % yield , 3 h) and fructose (47.9 % yield , 3 h) on Pt–KC 3 N 4 , with concurrent production of H 2 (233.8 μmol g −1 ). The results of in situ NH 3 –temperature-programmed desorption (TPD) characterization demonstrated that light irradiation induced the formation of transient LASs on Pt–KC 3 N 4 , and the density of acid sites observed in this study differed significantly from that observed in offline data. Furthermore, theoretical calculations demonstrated that photothermal electron redistribution on Pt–KC 3 N 4 is the main factor driving this transient LAS formation. This report describes a unique methodology to explore transient acid sites in isomerization reactions and provides insight into potential applications in the field of photocatalytic biomass valorization.