Understanding the Light-Triggered Process of a Photo Rechargeable Battery via Fluorescence Studies of Its Constitutional Photo- and Electroactive Components

Solar energy is a standout clean and renewable energy source. Indeed, sunlight can efficiently be converted to electricity. However, solar energy must be stored for use during dark periods because of its intermittency. To address this challenge, we report a fundamental photophysical study for advancing an all-in-one photobattery for harvesting photons in addition to converting and storing energy. Focus was placed on assessing the photophysical properties of a light-harvesting organic dye, perelyene diimide (PDI), and its capacity to promote photo-oxidation of a lithium-ion batterys electroactive positive material. Electron transfer kinetics between perelyene diimide and carbon-coated lithium iron phosphate (cLFP) were measured by both steady-state and time-revolved emission and they were ca. 10(10) M-1 s(-1). Lifetime analyses showed that the PDIs intrinsic fluorescence was deactivated by cLFP through a mixed quenching mechanism. Various ceramics that are used as battery cathodes were also screened (LiCoO2, LiNi0.33Mn0.33Co0.33O2, LiNi0.8Co0.15Al0.05O2, and LiMn2O4) by fluorescence quenching of PDI. Both the carbon black coating and the oxidation state of the metal were found to play important roles in enabling the electronic transfer.