Enhancing dye-sensitized solar cell performance; optimization of quaternary counterion-based gel polymer electrolyte without changing additives or net-ion composition
T. M. W. J. Bandara, K. M. S. P. Bandara, H. M. N. Wickramasinghe, L. R. A. K. Bandara, N. M. Adassooriya, Kapila Wijayaratne
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引用次数: 0
Abstract
A series of novel gel polymer electrolytes (GPEs) was developed for quasi-solid-state dye-sensitized solar cells (DSSCs), to enhance their performance via mixed counterion effect. Here, LiI, CsI, tetrahexylammonium iodide (Hex4NI), and 1-methyl-3-propylimidazolium iodide (MPII) were used as iodide salts for the preparation of this new GPE. The electrolyte series was investigated by varying the molar fractions of LiI and CsI, keeping the molar fractions of Hex4NI and MPII constant. The molar composition of the iodide salts in electrolytes is MPII0.25(Hex4NI)0.8CsI(2-x)LiIx, where x is the variable. The temperature dependence of conductivity showed Vogel-Tammann-Fulcher behavior. The sample with x = 0.72, where LiI to CsI to Hex4NI to MPII molar ratio is 72:48:80:25, which gave 8.42 mS cm−1 at 30 °C, displayed the maximum conductivity at all the temperatures. The dependence of the complex AC conductivity on frequency is examined in detail to study the impacts of dielectric polarization effects of the GPEs. Quasi-solid-state DSSCs were constructed by utilizing six-layered TiO2 photoelectrodes, Pt counter electrode, and the novel GPE series. The three-salt electrolytes, containing LiI only and CsI only, containing DSSC showed efficiencies of 5.72% and 3.53% respectively. The four-salt system, which is composed of LiI to CsI to Hex4NI to MPII with a molar ratio of 96:24:80:25, demonstrated the highest solar cell efficiency of 7.42%, due to the collective contribution of Hex4N+, MPI+, Cs+, and Li+ ions in improving the charge transport in the electrolyte system. This study shows that DSSC performance can greatly be improved by optimizing counterion ratios without changing total ions in the electrolyte.
期刊介绍:
The Journal of Solid State Electrochemistry is devoted to all aspects of solid-state chemistry and solid-state physics in electrochemistry.
The Journal of Solid State Electrochemistry publishes papers on all aspects of electrochemistry of solid compounds, including experimental and theoretical, basic and applied work. It equally publishes papers on the thermodynamics and kinetics of electrochemical reactions if at least one actively participating phase is solid. Also of interest are articles on the transport of ions and electrons in solids whenever these processes are relevant to electrochemical reactions and on the use of solid-state electrochemical reactions in the analysis of solids and their surfaces.
The journal covers solid-state electrochemistry and focusses on the following fields: mechanisms of solid-state electrochemical reactions, semiconductor electrochemistry, electrochemical batteries, accumulators and fuel cells, electrochemical mineral leaching, galvanic metal plating, electrochemical potential memory devices, solid-state electrochemical sensors, ion and electron transport in solid materials and polymers, electrocatalysis, photoelectrochemistry, corrosion of solid materials, solid-state electroanalysis, electrochemical machining of materials, electrochromism and electrochromic devices, new electrochemical solid-state synthesis.
The Journal of Solid State Electrochemistry makes the professional in research and industry aware of this swift progress and its importance for future developments and success in the above-mentioned fields.