Degradation analysis of dye-sensitized solar cell module consisting of 22 unit cells for thermal stability: Raman spectroscopy study

• Published in: Solar energy 2016-06, Vol.130, p.244-249
• Main Authors: Kwak, Cheol Hwan, Baeg, Je Hyun, Yang, In Mo, Giribabu, Krishnan, Lee, Sunmook, Huh, Yun Suk
• Format: Article
• Language: English
• Subjects: DSSC module; Dye-sensitized solar cell; Dyes; Electrodes; Energy efficiency; Photovoltaic cells; Raman spectroscopy; Solar cells; Solar energy; Spectroscopy; Spectrum analysis; Thermal stability; Titanium dioxide; Z-907
• ISSN: 0038-092X; 1471-1257
• DOI: 10.1016/j.solener.2016.02.017

The degradation of a DSSC module consisting of 22 unit cells was systematically investigated using Raman spectroscopy and 2D Raman mapping. [Display omitted] •A large-scale DSSC module (30×30cm2) was fabricated.•A thermal degradation of the DSSC module reduced the power conversion efficiency.•The degradation of DSSC module was analyzed by Raman spectroscopy.•2D Raman mapping revealed the degradation factors in large-scale DSSC module. This study investigated the degradation of a DSSC module consisting of 22 unit cells for thermal stability. A 1000-h thermal stability test was conducted at 85°C, after which the cells maintained ca. 73.5% of their initial overall power conversion efficiency (η). The degradation was also systematically investigated using Raman spectroscopy. The results revealed that loss of the overall power conversion efficiency was due to (i) desorption of the Z-907 dye from the TiO2 electrode, and (ii) dissociation of SCN− from the Z-907 dye. In addition, analyses of 2D Raman mapping determined the following factors after the thermal stability test: (i) the defect vacancy of Z-907 on the TiO2 surface in the cell, (ii) the leakage of the desorbed Z-907 into the sealing material from the cell, and (iii) the dissociation of SCN− ligand throughout the cell.