4′‐Chlorochalcone‐Assisted Electroactive Polyvinylidene Fluoride Film‐Based Energy‐Storage System Capable of Self‐Charging Under Light

A simple photovoltaically self‐charging energy‐storage system (PSESS) has been fabricated as an effective solar energy‐storage power cell. The PSESS is capable of the in situ storage of visible light energy in the form of electrical energy. The PSESS is assembled on a photoelectrode (fluorine‐doped tin oxide) that contained a dye‐sensitized and hole‐trapping phenosafranine–polyvinylpyrrolidone film in association with an electroactive and highly dielectric chlorochalcone–polyvinylidene fluoride (PVDF) film, in which photogenerated electrons are stored. Here, chlorochalcone particles act as a catalytic agent for electroactive β crystal nucleation, visible‐light emission, and the improved dielectric value of the composite thin films. A proportion of 85 % electroactive β phase nucleation and a high dielectric constant (≈60) are achieved by incorporating 20 mass % chlorochalcone in PVDF. The self‐charging capability of the PSESS was verified under a light illumination intensity of 110 mW cm−2. The PSESS was charged up to 0.95 V under light illumination. Moreover, the device wass discharged with a constant current density 1.25 mA g−1 for a long time (≈560 min) after the light was switched off. The photogenerated energy and charge density of the PSESS are approximately 5.25 mWh g−1 and 42 C g−1, respectively. The maximum capacitance attained under the light illumination is approximately 44 F g−1, which is many times greater than two‐electrode self‐charged photovoltaic cells reported previously. A blue light‐emitting diode can be driven by using the PSESSs as a power bank. Charge it up! A simple, light‐weight, and cost‐effective two‐electrode photoinduced energy‐storage system, denoted as a photovoltaically self‐charging energy‐storage system, with a good recycling performance is developed. Good energy density and storage capacity are achieved. PVDF=polyvinylidene fluoride, PCC=PVDF–chlorochalcone composite, PVP=polyvinylpyrrolidone