Fig. 4: Redox cycle mechanism mediated by photoinduced anion radical intermediate.
From: A photocatalytic redox cycle over a polyimide catalyst drives efficient solar-to-H2O2 conversion
a H2O2 production on the PI-BD-TPB aerogel under different control conditions, Error bars on mean values are standard deviations of three independent tests, reaction conditions: catalyst (50 mg), water (25 mL), Ar atmosphere in the light or O2 atmosphere in the dark. b In situ FTIR spectrum of the PI-BD-TPB aerogel with Ar atmosphere under 300 W Xe lamp and O2 gas purging in the dark at 1200–2000 cm−1 and 2700–2900 cm−1, the peak intensity of H2O2 species on “Light-Ar /Dark-O2” condition. c Isotopic experiments with 18O2 or H218O for H2O2 production on the PI-BD-TPB photocatalyst, See Supplementary Table 2 for more detailed information. d 1H spectrum of H2O2 in D2O. e 1H spectrum of the photocatalytic D2O2 production of the BD-TPB in D2O. f Calculated free energy diagrams of H2O2 production from O2 reduction pathway by model systems of C = O state (BD-TPB) and radical anions state (BD-TPB*), respectively. g Key steps of H2O2 production from O2 reduction pathway on the PI-BD-TPB aerogel photocatalyst.
