Mesoporous TiO2 nanoparticle (NP) films are broadly used as electrodes in photoelectrochemical cells, dye-sensitized solar cells (DSSCs), and perovskite solar cells (PSCs). State-of-the-art mesoporous TiO2 NP films for these solar cells are fabricated by annealing TiO2 paste-coated fluorine-doped tin oxide glass in a box furnace at 500 °C for ≈30 min. Here, the use of a nontraditional reactor, i.e., flame, is reported for the high throughput and ultrafast annealing of TiO2 paste (≈1 min). This flame-annealing method, compared to conventional furnace annealing, exhibits three distinct benefits. First, flame removes polymeric binders in the initial TiO2 paste more completely because of its high temperature (≈1000 °C). Second, flame induces strong interconnections between TiO2 nanoparticles without affecting the underlying transparent conducting oxide substrate. Third, the flame-induced carbothermic reduction on the TiO2 surface facilitates charge injection from the dye/perovskite to TiO2. Consequently, when the flame-annealed mesoporous TiO2 film is used to fabricate DSSCs and PSCs, both exhibit enhanced charge transport and higher power conversion efficiencies than those fabricated using furnace-annealed TiO2 films. Finally, when the ultrafast flame-annealing method is combined with a fast dye-coating method to fabricate DSSC devices, its total fabrication time is reduced from over 3 h to ≈10 min.
Bibliographical noteFunding Information:
This work was supported by C1 Gas Refinery Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (2016M3D3A1A01913254). This research was also supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea (No. 20163010012450). J. K. Kim acknowledges the support from the Yonsei University Future-leading Research Initiative of 2015 (2015-22-0067 ). J.K.K and S.U.C. contributed equally to this work.
© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
All Science Journal Classification (ASJC) codes
- Materials Science(all)