The critical role of furfural alcohol in photocatalytic H2O2 production on TiO2

Isopropanol is frequently employed as the electron donor to facilitate hole transfer and promote photocatalytic H 2 O 2 production. However, the role of alcohols can be more complicated due to the interaction with TiO 2 . According to a comparison of aliphatic, aromatic and aromatic heterocyclic alcohols on photocatalytic H 2 O 2 production on TiO 2 , furfural alcohol (FFA) displays superior capability to others. The presence of alcohols with aromatic structures can significantly accelerate formation and suppress decomposition of H 2 O 2 . Moreover, furfural alcohol tends to form more stable complexes on TiO 2 surface, which can negatively shift the flat band position, induce visible light activity, and boost two-electron reduction of oxygen. The altered electron transfer pathway for H 2 O 2 production was indicated by the Koutecky-Levich plots, the less pH dependence, and the signals of peroxide species in Raman spectra. This study brings insights for modulating the interfacial oxygen reduction and designing highly efficient and selective H 2 O 2 production photocatalytic systems.