title: New organic donor-acceptor-π-acceptor sensitizers for efficient dye-sensitized solar cells and photocatalytic hydrogen evolution under visible-light irradiation.
abstract: Two organic donor-acceptor-π-acceptor (D-A-π-A) sensitizers (AQ and AP), containing quinoxaline/pyrido[3,4-b]pyrazine as the auxiliary acceptor, have been. Through fine-tuning of the auxiliary acceptor, a higher designed and synthesized photoelectric conversion efficiency of 6.02% for the AQ-based dye-sensitized solar cells under standard global AM1.5 solar conditions was achieved. Also, it was found that AQ-Pt/TiO2 photocatalysts displayed a better rate of H2 evolution under visible-light irradiation (420 nm<λ<780 nm) because of the stability of the oxidized states and the lower rates of electron recombination. Importantly, sensitizers AQ and AP-Pt/TiO2 showed strong photocatalytic activity during continuous light soaking for 10 h with methanol as the sacrificial electron donor. Additionally, the processes of their intermolecular electron transfer were further investigated theoretically by using time-dependent DFT. The calculated results indicate that the auxiliary acceptor plays the role of an electron trap and results in broad spectral responses.
authors.affiliation: Key Laboratory for Advanced Materials, Institute of Fine Chemicals, East China University of Science and Technology, Shanghai 200237 (P.R. China), Fax: (+86) 21-64252758.
authors.forename: Xing
authors.initials: X
authors.lastname: Li
authors.forename: Shicong
authors.initials: S
authors.lastname: Cui
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhou
authors.forename: Hao
authors.initials: H
authors.lastname: Zhou
authors.forename: Yue
authors.initials: Y
authors.lastname: Hu
authors.forename: Jin-Gang
authors.initials: JG
authors.lastname: Liu
authors.forename: Yitao
authors.initials: Y
authors.lastname: Long
authors.forename: Wenjun
authors.initials: W
authors.lastname: Wu
authors.forename: Jianli
authors.initials: J
authors.lastname: Hua
authors.forename: He
authors.initials: H
authors.lastname: Tian
mesh_terms: D011211:Electric Power Supplies; D006859:Hydrogen / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D056004:Molecular Dynamics Simulation; D010777:Photochemistry / Q000379:methods; D011719:Pyrazines / Q000138:chemical synthesis* / Q000737:chemistry; D011810:Quinoxalines / Q000138:chemical synthesis* / Q000737:chemistry; D012993:Solar Energy; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet
chemical_list: D011719:Pyrazines; D011810:Quinoxalines; D006859:Hydrogen
keywords: donor-acceptor systems; dyes/pigments; photochemistry; sensitizers; solar cells