Effect of Sintering Profiles on Titania Interparticle Connectivity, Electron Transport and Interfacial Resistance in Dye-Sensitized Solar Cells

Abstract:

TiO₂ films, which are often sintered at 450°C for 30 or 60 minutes for application in dye-sensitized solar cells (DSSCs), show no appreciable connectivity between the TiO₂ particles. The present work deals with connectivity between TiO₂ particles and its effect on electron diffusion and short circuit current density (J_sc) of DSSCs made from TiO₂ films sintered at lower temperature for longer time (450°C, 550°C, 650°C for 60 minutes) and higher temperature for shorter time (450°C for 60 min followed by 700°C and 800°C for 10 and 20 minutes). TiO₂ films sintered at higher temperature (700°C) but for shorter time (10 min) exhibited better connectivity between the particles with slight reduction in surface area. This caused faster transport of electron through the films sintered at 700°C/10 min than 450°C/60 min and 550°C/60 min and hence, resulted in highest J_sc (~ 7 mA/cm²). Films sintered at 650°C/60 min and 700°C/20 min showed better interparticle connectivity but had significantly lower surface area, dye loading and therefore, despite faster diffusion of electron in these films J_sc was measured to be lower. Sintering at 700°C/10 min following 450°C/60 min could be considered the best in terms of dye loading, electron transport and efficiency.

• Periodical: Materials Science Forum (Volume 771)
• Pages: 143-157
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.771.143
• Online since: October 2013
• Authors: Ajay K. Jena, Shyama Prasad Mohanty, Parag Bhargava
• Keywords: Dye-Sensitized Solar Cell, Electron Life Time, Electron Transport, Interparticle Connectivity, Nanoindentation, Sintering Temperature

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