Polarization-induced carrier separation in conjugated polyimide for boosted visible light driven H2O2 production

Abstract

Ternary carbon nitride oxygen semiconductors have been developed as metal-free catalysts for photocatalysis, but the efficiencies are still far from satisfaction. Herein, we report that polarization adjusted conjugated polyimide (PIK) can be substantially optimized the activity of visible-light induced H2O2 production. The structures of catalyst have been well characterized by XRD, FTIR, BET and XPS. Compared with bulk polyimide, optimized PIK1.5 displays 117-folds-enhanced photocatalytic H2O2 production under visible light (λ ≥ 420 nm), achieving an excellent H2O2 production rate of 160.5 umol·g·h−1. Fluorescence spectroscopic measurements confirm that reinforced photocatalytic H2O2 production is mainly attributed to the increased polarization in conjugated polyimide, which effectively accelerates the separation and migration kinetics of electron-hole pairs. These results indicate that polarization play an important role in polymeric semiconductors for solar energy utilization.