Judicious Molecular Design of 5H‑Dithieno[3,2‑b:2',3'‑d]Pyran-based Hole-Transporting Materials for Highly Efficient and Stable Perovskite Solar Cells.

The structural modification of hole-transporting materials (HTMs) is an effective strategy for enhancing photovoltaic performance in perovskite solar cells (PSCs). Herein, a series of dithienopyran (DTP)-based HTMs (Me-H, Ph-H, CF3-H, CF3-mF, and CF3-oF) is designed and synthesized by substituting different functional groups on the DTP unit and are used fabricating PSCs. In comparison with Me-H having two methyl substituents on the dithienopyrano ring, the Ph-H having two phenyl substituents on the ring exhibits higher PCEs.

Anion Effect on the Cu-Neocuproine Mediator and Its Electrocatalysts for Dye-Sensitized Solar Cells: Polymeric Chalcogenides of PEDOT-PEDTT and [Ag(SePh)].

The synthetical methodology for the [Cu(dmp)] (dmp = 2,9-dimethyl-1,10-phenanthroline; neocuproine) complexes has been systematically investigated by using various copper precursors, including CuCl, Cu(NO), and Cu(ClO). After an anion exchange to trifluoromethanesulfonimide (TFSI), the tetra-coordinated Cu(dmp)(TFSI)-Cu(ClO) (7.43%) outperformed the penta-coordinated Cu(dmp)(TFSI)(NO)-Cu(NO) (4.

Structural Engineering of Organic D-A-Ï€-A Dyes Incorporated with a Dibutyl-Fluorene Moiety for High-Performance Dye-Sensitized Solar Cells.

Structural engineering of the light-harvesting dyes employed in DSSCs (dye-sensitized solar cells) with a systematic choice of the electron-donating and -accepting groups as well as the π-bridge allows the (photo)physical properties of dyes to match the criteria needed for improving the DSSC efficiency. Herein, we report an effective approach of molecular engineering of DSSC sensitizers, aiming to gain insights on the configurational impact of the fluorenyl unit on the optoelectronic properties and photovoltaic performance of DSSCs. Five new organic dyes (, , , , and ) with a D-A-π-A framework integrated with a fluorenyl moiety were designed and synthesized for DSSCs.

Iodide-free ionic liquid with dual redox couples for dye-sensitized solar cells with high open-circuit voltage.

A novel ionic-liquid mediator, 1-butyl-3-{2-oxo-2-[(2,2,6,6-tetramethylpiperidin-4-yl)amino]ethyl}-1H-imidazol-3-ium selenocyanate (ITSeCN), has been successfully synthesized for dye-sensitized solar cells (DSSCs). ITSeCN possesses dual redox channels, imidazolium-functionalized 2,2,6,6-tetramethylpiperidine N-oxyl (TEMPO) and selenocyanate, which can serve as the cationic redox mediator and the anionic redox mediator, respectively. Therefore, ITSeCN has a favorable redox nature, which results in a more positive standard potential, larger diffusivity, and better kinetic heterogeneous rate constant than those of iodide.

Structure-performance correlations of organic dyes with an electron-deficient diphenylquinoxaline moiety for dye-sensitized solar cells.

The high performances of dye-sensitized solar cells (DSSCs) based on seven new dyes are disclosed. Herein, the synthesis and electrochemical and photophysical properties of a series of intentionally designed dipolar organic dyes and their application in DSSCs are reported. The molecular structures of the seven organic dyes are composed of a triphenylamine group as an electron donor, a cyanoacrylic acid as an electron acceptor, and an electron-deficient diphenylquinoxaline moiety integrated in the π-conjugated spacer between the electron donor and acceptor moieties.

Ionic liquid with a dual-redox couple for efficient dye-sensitized solar cells.

A new type of ionic liquid that contains a nitroxide radical (N-O(.)) and iodide as two redox couples, JC-IL, has been successfully synthesized for high-performance dye-sensitized solar cells (DSSCs). Both of the redox couples exhibit distinct redox potentials and attractive electrochemical characteristics.

High-performance dipolar organic dyes with an electron-deficient diphenylquinoxaline moiety in the π-conjugation framework for dye-sensitized solar cells.

We report here the synthesis and electrochemical and photophysical properties of a series of easily prepared dipolar organic dyes and their application in dye-sensitized solar cells (DSSCs). For the six organic dyes, the molecular structures comprised a triphenylamine group as an electron donor, a cyanoacrylic acid as an electron acceptor, and an electron-deficient diphenylquinoxaline moiety integrated in the π-conjugated spacer between the electron donor and acceptor moieties. The incorporation of the electron-deficient diphenylquinoxaline moiety effectively reduces the energy gap of the dyes and broadly extends the spectral coverage.

Synthesis of 3-alkoxymethylcoumarin from 3-cyanochromene via a novel intermediate 2-phenylimino-3-alkoxymethylchromene.

In this paper a concise, efficient, and environmentally benign method for the synthesis of 3-alkoxymethylcoumarin is described. From the reaction of 3-cyanochromene with an alkoxide and arylamine in THF, (Z)-2-phenylimino-3-alkoxymethylchromene was obtained as a novel intermediate via an isomerization of the double bond, a 1,2-addition of alkoxide, a Michael-type addition of aniline, an another isomerization of double bond and an elimination of ammonia. Subsequently, the intermediate was converted into the desired coumarin by treatment with 15% HCl in THF in good yield.