Three novel dithieno[3,2- f :2′,3′- h ]quinoxaline-based organic dyes ( IQ-C, IQ-D and IQ-F ) with three π-spacers were synthesized and developed for dye sensitized solar cells, where dithieno[3,2- f :2′,3′- h ]quinoxaline was used as electron-withdrawing π-spacers, and 2,3-diphenylquinoxaline or dibenzo[ a,c ]phenazine as auxiliary electron-withdrawing π-spacers. The dye IQ-D with 2,3-diphenylquinoxaline as auxiliary electron-withdrawing π-spacer exhibited higher photocurrent ( J sc ) and photovoltage ( V oc ) than that of the dye IQ-C with 2,3-bis(4-(octyloxy)phenyl)quinoxaline as the additional electron-withdrawing π-spacer, due to the larger adsorption amount of IQ-D . The dye IQ-F with a rigid conjugated dibenzo[ a,c ]phenazine as additional electron-withdrawing π-spacer showed the highest efficiency of 6.54% under AM 1.5 G irradiation. It was demonstrated that the π-spacers influence the photovoltaic performance of the dithieno[3,2- f :2′,3′- h ]quinoxaline-based organic dyes significantly. The results indicated that the dyes with three π-spacers are promising candidates for efficient dye-sensitized solar cells.
Donor-Acceptor (D-A) copolymers are critical for cost-effective and energy-efficient electrochromic devices (ECDs) and smart windows. In this study, a type of copolymers with dual-introduction of alkyl thiophene as π spacer and fluorine are designed for highly efficient ECDs, contributing to superior color efficiency (CE). Through π spacer modification, the twist angle as well as the optical bandgap of the copolymers (PDT-Th-BT) are minimized via blocking the F…O noncovalent repulsive interaction. ECDs based on PDT-Th-BT1F are achieved with high CE of 1440 cm²/C, along with electrochromic contrast up to 41.6%. This CE is the best yet among ECDs based on fluorination D-A type copolymers according to literature. Furthermore, smart window made from PDT-Th-BT1F contribute a 5 ℃ cooling down compared to the glass in the building models and an energy saving of 631,257.14 kWh in a 26,404.54 m 2 building model, greatly conducive to environmental protection. This work presents a viable strategy for the development of highly efficient ECDs and smart windows.
危险品化学品经营许可证（带存储）