Low-temperature versus oxygen plasma treatment of water-based TiO2 paste for dye-sensitized solar cells

• Published in: Journal of sol-gel science and technology 2013-10, Vol.68 (1), p.67-74
• Main Authors: HOCEVAR, Mateja, OPARA KRASOVEC, Urša, TOPIC, Marko
• Format: Article
• Language: English
• Subjects: Anatase; Applied sciences; Ceramics; Chemistry; Chemistry and Materials Science; Colloidal gels. Colloidal sols; Colloidal state and disperse state; Composites; Crystallization; Dye-sensitized solar cells; Dyes; Energy; Exact sciences and technology; General and physical chemistry; Glass; High temperature; Inorganic Chemistry; Low temperature; Materials Science; Nanoparticles; Nanotechnology; Natural energy; Natural Materials; Nickel base alloys; Optical and Electronic Materials; Original Paper; Oxygen plasma; Pastes; Photovoltaic cells; Photovoltaic conversion; Plasma; Production costs; Sol gel process; Sol-gel processes; Solar cells; Solar cells. Photoelectrochemical cells; Solar energy; Substrates; Superalloys; Temperature; Titanium dioxide
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1007/s10971-013-3135-1

High-temperature treatment steps in fabrication process of dye sensitized solar cell (DSSC) significantly contribute to the manufacturing costs and limit the use of temperature sensitive substrates. Therefore our aim was to develop a simple method for the preparation of water-based TiO 2 paste. The paste is based on peroxotitanic acid (PTA) sol–gel matrix and commercial TiO 2 nanoparticles (P25). Two fabrication processes to decompose/transform the PTA matrix in the printed TiO 2 layer are explored and combined: annealing at temperatures up to 250 °C and/or oxygen plasma treatment. The results show that the PTA matrix in the paste converts to anatase phase and to some extent also attaches to the TiO 2 nanoparticles P25 acting as an interconnecting network within TiO 2 layer. The transformation of the PTA matrix occurs around 250 °C, but in the presence of TiO 2 nanoparticles P25 it starts already at 120 °C. In addition the results reveal that the crystallization is achievable also solely with the oxygen plasma treatment. The efficiency of the TiO 2 layers, exposed to different post-deposition treatments, is evaluated in DSSCs. The results show that oxygen plasma treatment of the TiO 2 layers could efficiently replace temperature curing at 250 °C. Within this study the DSSCs with the efficiency up to 4.2 % measured under standard test conditions (1,000 W/m 2 , AM1.5, 25 °C) were realized.