A Stable Panchromatic Green Dual Acceptor, Dual Donor Organic Dye for Dye-Sensitized Solar Cells

A novel organic sensitizer (AP3) with dual donors and dual anchor-acceptors based on an electron deficient thieno[3,4-b]pyrazine (TPz) pi-bridge was synthesized, which shows an impressively high J(sc) of 17.6 mA/cm(2) when cosensitized with D35 (12.4 mA/cm(2) as a single dye). Device power conversion efficiencies were observed at 7.5% under full sun intensity and in excess of 10% under reduced sun intensity. This novel dye design approach allows for devices showing photostability beyond 500 h for continuous irradiation and a tunable dye structure with an incident power conversion efficiency breadth reaching 800 nm from a simple-to-synthesize organic dye. Dye characterization with cyclic voltammetry, solution and film absorption, and computational analysis are all presented. Additionally, device characterization was performed through IV curves, IPCE, electron lifetime measurements, transient absorption spectroscopy, and current dynamic measurements at varying sun intensities to better understand the origin of the high device power conversion efficiencies as well as the interactions of AP3 and D35 in DSC devices.