title: Bis(phenothiazyl-ethynylene)-Based Organic Dyes Containing Di-Anchoring Groups with Efficiency Comparable to N719 for Dye-Sensitized Solar Cells.
abstract: A new series of acetylene-bridged phenothiazine-based di-anchoring dyes have been synthesized, fully characterized, and used as the photoactive layer for the fabrication of conventional dye-sensitized solar cells (DSSCs). Tuning of their photophysical and electrochemical properties using different π-conjugated aromatic rings as the central bridges has been demonstrated. This molecular design strategy successfully inhibits the undesirable charge recombination and prolongs the electron lifetime significantly to improve the power conversion efficiency (η), which was proven by the detailed studies of electrochemical impedance spectroscopy (EIS) and open-circuit voltage decay (OCVD). Under a standard air mass (AM) 1.5 irradiation (100 mW cm-2), the DSSC based on the dye with phenyl bridging unit exhibits the highest η of 7.44 % with open-circuit photovoltage (Voc) of 0.796 V, short-circuit photocurrent density (Jsc) of 12.49 mA cm-2and fill factor (ff) of 0.748. This η value is comparable to that of the benchmark N719 under the same conditions.
authors.affiliation: Institute of Molecular Functional Materials, Department of Chemistry and Institute of Advanced Materials, Hong Kong Baptist University, Waterloo Road, Kowloon Tong, Hong Kong, P.R. China.
authors.forename: Chi-Ho
authors.initials: CH
authors.lastname: Siu
authors.affiliation: Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, P.R. China.
authors.forename: Lawrence Tien Lin
authors.initials: LT
authors.lastname: Lee
authors.affiliation: Institute of Molecular Functional Materials, Department of Chemistry and Institute of Advanced Materials, Hong Kong Baptist University, Waterloo Road, Kowloon Tong, Hong Kong, P.R. China.|HKBU Institute of Research and Continuing Education, Shenzhen Virtual University Park, Shenzhen, 518057, P.R. China.
authors.forename: Po-Yu
authors.initials: PY
authors.lastname: Ho
authors.affiliation: Institute of Molecular Functional Materials, Department of Chemistry and Institute of Advanced Materials, Hong Kong Baptist University, Waterloo Road, Kowloon Tong, Hong Kong, P.R. China.|HKBU Institute of Research and Continuing Education, Shenzhen Virtual University Park, Shenzhen, 518057, P.R. China.
authors.forename: Cheuk-Lam
authors.identifier: http://orcid.org/0000-0001-8596-0307
authors.initials: CL
authors.lastname: Ho
authors.affiliation: Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, P.R. China.|Department of Materials Science and Engineering, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, P.R. China.
authors.forename: Tao
authors.initials: T
authors.lastname: Chen
authors.affiliation: Department of Chemistry and Faculty of Science, Center of Nanotechnology, Kasetsart University, Chatuchak, Bangkok, 10900, Thailand.
authors.forename: Songwut
authors.initials: S
authors.lastname: Suramitr
authors.affiliation: Department of Chemistry and Faculty of Science, Center of Nanotechnology, Kasetsart University, Chatuchak, Bangkok, 10900, Thailand.
authors.forename: Supa
authors.initials: S
authors.lastname: Hannongbua
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, 5625 Renmin Street, Changchun, 130022, P.R. China.
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Xie
authors.affiliation: Institute of Advanced Energy Materials, Fuzhou University, Fuzhou, Fujian, 350002, P.R. China.
authors.forename: Mingdeng
authors.initials: M
authors.lastname: Wei
authors.affiliation: Institute of Molecular Functional Materials, Department of Chemistry and Institute of Advanced Materials, Hong Kong Baptist University, Waterloo Road, Kowloon Tong, Hong Kong, P.R. China.|Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, P.R. China.|HKBU Institute of Research and Continuing Education, Shenzhen Virtual University Park, Shenzhen, 518057, P.R. China.|Institute of Advanced Energy Materials, Fuzhou University, Fuzhou, Fujian, 350002, P.R. China.
authors.forename: Wai-Yeung
authors.identifier: http://orcid.org/0000-0002-9949-7525
authors.initials: WY
authors.lastname: Wong
keywords: bridging units; charge recombination; dyes; sensitizers; solar cells