Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (11): 2669-2675.doi: 10.3866/PKU.WHXB201206191

• ELECTROCHEMISTRY AND NEW ENERGY • Previous Articles     Next Articles

Influence of Polymer Gel Electrolyte on the Performance of Dye-Sensitized Solar Cells Analyzed by Electrochemical Impedance Spectroscopy

DAI Yu-Hua1, LI Xiao-Jie1,2, FANG Yan-Yan3, SHI Qiu-Fei1, LIN Yuan3, YANG Ming-Shan1   

  1. 1. Beijing Key Laboratory of Special Elastomer Composite Materials, Department of Materials Science and Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, P. R. China;
    2. College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China;
    3. Key Laboratory of Photochemistry, Center for Molecular Sciences, Institute of Chemistry , Chinese Academy of Sciences, Beijing 100080, P. R. China
  • Received:2012-04-06 Revised:2012-06-18 Published:2012-10-17
  • Contact: DAI Yu-Hua
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (51103013), Scientific Research Project of Beijing Municipal Education Commission, China (KM201110017007) and Funding Project for Academic Human Resources Development in Institutions of Higher Learning under the Jurisdiction of Beijing Municipality, China (PHR201108359).


The effects of gel electrolyte polymer matrix structure and composition on the photovoltaic properties of quasi-solid state dye-sensitized solar cells (DSSCs) were investigated using two series of copolymers, poly(hydroxy ethyl methacrylate-N-vinyl) pyrrolidone P(HEMA-NVP) and poly(methyl methacrylate- N-vinyl pyrrolidone) P(MMA-NVP), by electrochemical impedance spectroscopy (EIS). P(HEMA-NVP) copolymers with various crosslinking agent and N-vinyl pyrrolidone (NVP) contents, as well as P(MMA-NVP) copolymers with various NVP content, absorbed liquid electrolyte to form gel electrolytes HGelI, HGelII, and MGel, respectively. It was found that with increasing copolymer P(HEMA-NVP) crosslinking agent content, from 0.1 to 0.6% (w), the power conversion efficiency (η) of DSSCs based on HGelI initially increased and then decreased. A maximum conversion efficiency of 5.54% at 100 mW·cm-2 was observed when crosslinker content was 0.4% (w). Meanwhile, we compared the parameters of DSSCs based on HGelII with those of DSSCs based on MGel. The conversion efficiencies of the former, which contained hydroxy groups, were all higher than those of the latter, while the open circuit voltages (Voc) of the latter were larger than those of the former. DSSCs assembled with HGelII with a HEMA content of 60% exhibited the highest conversion efficiency, at 100 mW·cm-2. Electrochemical impedance spectroscopy (EIS) investigations showed that copolymer crosslinking structure affected the internal resistance and ionic conductivity of the resulting DSSCs, while addition of hydroxy groups decreased the interfacial resistance. Thus, the photovoltaic performance of DSSCs can be improved by tuning the crosslinking structure and the hydroxy content of the copolymer.

Key words: Dye-sensitized solar cell, Polymer electrolyte, Electrochemical impedance spectroscopy, Hydroxy group, Crosslinking structure, Photovoltaic performance