The n-ssDSCs were prepared on the basis of published work by Chiang et al. and Xu et al. A compact TiO2 blocking layer was deposited by spray pyrolysis with an airbrush onto etched and cleaned FTO glass substrates on a hotplate at 450 °C. Before deposition, the samples were ozone treated for 15 min and preheated for 15 min at 450 °C. For an area of 100 cm 2 , 7 mL of a solution of 0.6 mL of titanium diisopropoxide bis(acetylacetonate), 0.4 mL acetylacetone and 9 mL pure ethanol was used. The films were left to anneal on the hotplate for 30 min and then cooled down to room temperature slowly under ambient air. For the mesoporous TiO2 layer, a diluted TiO2 paste (1:3 ethanol to Dyesol, 30NR-T w/w) was used. Before deposition via spincoating (150 µL, 10s acceleration to 3000 rpm, then 30 s at 3000 rpm), the films were ozone treated for 10 min. The spin coating procedure was repeated the desired times and after each layer, the films were allowed to dry on a hotplate at 115 °C for 5 min. Following the sintering process of the TiO2 film on a hotplate at 500 °C for 30 min, the film was allowed to cool to room temperature. Subsequently, it was submerged in a 0.02 M aqueous TiCl4 solution at 70 °C for 30 min. After rinsing with deionized water, the film was annealed on a hotplate at 500 °C in ambient atmosphere for 30 min. Once it cooled down to 60 °C, the film was placed in a 0.2 mM D35 in tert-butanol/acetonitrile (1:1 v/v) solution overnight for sensitization.