Abstract
Carrier dynamics modulation is intricately linked to semiconductor materials and device design. Elucidating carrier transport mechanisms and directing carrier transfer present significant yet arduous research challenges. Herein, we reveal the mechanism of charge transfer during accumulation and release through a series of in-situcharacterizations using Poly (heptanazinamide)（PHI) material as a model system. In contrast to previous reports of dark-state electron catalysis, the quantitative capture of holes and electron annihilation demonstrates that the catalytically active species in the dark-state charge release stage are holes rather than electrons. Specifically, the electrons captured during the photocharging stage are stored as long-lived radicals. Concurrently, holes are stored through hole scavenging. In the dark-state discharge stage, the released electrons reduce the oxidized hole sacrificial agents prompting the release of holes to participate in catalytic reactions. Analysis of the structural changes during the photocharging process suggests that the heptazine unit is destroyed and the carbonyl group formation underlie the observed charge storage phenomenon. This work provides insight into charge storage mechanisms and suggests potential applications in the development of self-charging devices.