功能化多壁碳纳米管填充的凝胶电解质在染料敏化太阳能电池的应用

Application of Functionalized Multi-walled Carbon Nanotubes Filled Gel Electrolyte in Dye-Sensitized Solar Cells

纯聚偏氟乙烯-六氟丙烯共聚物(PVDF-HFP)基凝胶电解质常常受制于低离子电导率,阻碍了其在染料敏化太阳电池(dye-sensitized solar cells,DSSCs)中的应用。而利用纳米填充可提高凝胶电解质离子电导率及凝胶电解质DSSCs的性能。本文使用功能化的多壁碳纳米管(f-MWCNT)作为PVDF-HFP凝胶电解质的纳米填充物,通过改变f-MWCNT的质量分数来研究其对电解质的离子电导率和离子扩散的影响,进而研究其对DSSCs的转化效率和长期稳定性的增强作用。研究发现:质量分数0.5%的f-MWCNT明显提高了 PVDF-HFP 凝胶电解质的离子电导率和离子扩散系数。并且,该凝胶电解质基DSSCs的光转换效率可达5.28%,相比于未填充的PVDF-HFP凝胶电解质基DSSCs(4.01%),其效率提高了31.7%。 42 d后,该电池依然可以保持最初转化效率的86.5%。实验结果证实了f-MWCNT在纳米填充方面的巨大潜能,为采用纳米填充物提高凝胶电解质DSSCs的性能提供参考。

Gel electrolyte based on pure polyvinylidene fluoride-six fluoropropene copolymer(PVDF-HFP) often suffers from low ionic conductivity, which hinders its application in dye-sensitized solar cells(DSSCs). However, the ionic conductivity of gel electrolyte and the conversion efficiency of the DSSCs can be enhanced by nanofillers. In this paper, we employed functionalized multi-walled carbon nanotube(f-MWCNT) as the nanofiller in the gel electrolyte based on PVDF-HFP. We studied its effect on ionic conductivity and ionic diffusion of electrolytes via changing the mass fraction of f-MWCNT, and investigated its improvement on the conversion efficiency and long-term stability of DSSCs. It was found that the PVDF-HFP gel electrolyte with 0.5% f-MWCNT significantly increased the ionic conductivity and ionic diffusion coefficient of the electrolyte. Moreover, the optimal conversion efficiency of the DSSCs with gel electrolyte reaches to 5.28%, which is 31.7% higher than that of the DSSCs with unfilled gel electrolyte(4.01%). After 42 days, the DSSCs still maintained 86.5% of the original conversion efficiency. The experiment confirms the great potential of f-MWCNT as the nanofiller, providing a reference for the study to improve the performance of the gel electrolyte DSSCs by nanofillers.