Excited Charge Separation in a π-Interacting Phenothiazine-Zinc Porphyrin-Fullerene Donor-Acceptor Conjugate.

We have designed, synthesized, and characterized a donor-acceptor triad, , that consists of a π-interacting phenothiazine-linked porphyrin as a donor and sensitizer and fullerene as an acceptor to seek charge separation upon photoexcitation. The optical absorption spectrum revealed red-shifted Soret and Q-bands of porphyrin due to charge transfer-type interactions involving the two ethynyl bridges carrying electron-rich and electron-poor substituents. The redox properties suggested that the phenothiazine-porphyrin part of the molecule is easier to oxidize and the fullerene part is easier to reduce.

Surface Reconstruction with Aprotic Trimethylsulfonium Iodide for Efficient and Stable Perovskite Solar Cells.

Organic ammonium salts are widely used for surface passivation to enhance the photovoltaic (PV) performance and stability of perovskite solar cells (PSCs). However, the protic nature of ammonium units results in the quick degradation of perovskites due to the hydrogen bonding interaction with water molecules. Recently, organo-sulfur compounds have attracted growing interest as passivation layers on three-dimensional perovskites due to their moisture-resistive behavior.

Molecular Engineering of Photosensitizers for Solid-State Dye-Sensitized Solar Cells: Recent Developments and Perspectives.

Dye-sensitized solar cells (DSSCs) are a feasible alternative to traditional silicon-based solar cells because of their low cost, eco-friendliness, flexibility, and acceptable device efficiency. In recent years, solid-state DSSCs (ss-DSSCs) have garnered much interest as they can overcome the leakage and evaporation issues of liquid electrolyte systems. However, the poor morphology of solid electrolytes and their interface with photoanodes can minimize the device performance.

Efficient Medium Bandgap Electron Acceptor Based on Diketopyrrolopyrrole and Furan for Efficient Ternary Organic Solar Cells.

We report the design of novel medium bandgap nonfullerene small molecule acceptor NFSMA with A-π-A-π-A architecture, with the molecular engineering of this material comprising a strong electron-accepting backbone unit DPP (A) as the acceptor, which is attached to the dicyanomethylene-3-hexylrhodanine (A) acceptor via a furan (π-spacer) linker. We systematically studied its structural and optoelectronic properties. The incorporation of dicyanomethylene-3-hexylrhodanine and furan enhance the light absorption and electrochemical properties by extending π-conjugation and is anticipated to improve by decreasing the LUMO level.

Butterfly architecture of NIR Aza-BODIPY small molecules decorated with phenothiazine or phenoxazine.

This is the first report on the highest efficiency NIR absorbing Aza-Bodipy small molecules. The molecular engineering of newly synthesized NIR absorbing Aza-Bodipy dyes consists of covalently linked phenothiazine (AZA-PTZ-BOD) and phenoxazine (AZA-POZ-BOD) moieties as terminal groups and Aza-Bodipy as a central core moiety. The highest efficiency for OPV devices of 8.