Research On Intercalation Hydrotalcite Composite Electrolyte Of The Dye-sensitized Solar Cell

Dye-sensitized solar cell(DSSC) has attracted extensive attention with its high theoretical conversion efficiency, low cost, simple preparation process and environment-tal friendly. Through the research and experiment for over ten years,DSSC has made great breakthrough which makes large-scale production possible.Even though DSSC with the conventional liquid electrolyte has high photoelectric conversion efficiency, there are some problems unsolved, such as leakage and difficulty with package. According to above-mentioned problems, this thesis developed the two-dimensional intercalation hydrotalcite composite quasi solid electrolyte. The generated quantum confinement effect significantly improved the photoelectric performance of DSSC.Firstly, we used the liquid deposition method to prepare the LDH which was characterized by the XRD and SEM test. Then we prepared a quasi solid state electrolyte with LDH of 0wt%, 3wt%, 5wt% and 7wt%, and carried out the electrochemical impedance spectroscopy and ion diffusion coefficient test. Finally, we assembled the DSSC and tested the dark current and their photoelectric conversion efficiency. The experimental results showed that, the photovoltaic properties of DSSC containing 5wt% LDH was optimal. In the standard conditions, the photoelectric conversion efficiency reached 2.05%, which was improved by 200%.Secondly, this thesis also studied the intercalation compounds of two kinds of hydrotalcite respectively, which were twelve alkyl sulfuric acid pillared hydrotalcite(LDH-DS) and stearic acid pillared hydrotalcite(LDH-St). We measured their interlayer distance from the original 0.78 nm, extended to 2.54 nm and 3.69 nm. Then we prepared quasi solid state electrolytes containing LDH-0wt%, LDH-5wt%,LDH-DS-5wt%, LDH-St-5wt%, and tested the electrochemical performance of the electrolytes and the photoelectric properties of the DSSC. The result showed that, the photovoltaic properties of the solar cell containing LDH-St-5wt%, which has the maximum interlayer distance, demonstrated the best photovoltaic properties, with the conversion efficiency reaching 3.44%.