Performance of post-hidrothermally treated xerogel TiO₂ dye-sensitized solar cell (DSSC) and its nanostructure characteristic

Dye-sensitized solar cell (DSSC) is one of photovoltaic solar cells, which is very favorable as alternative renewable energy source to anticipate the diminishing the fossil fuel due to its low-cost, ease of production and eco-friendliness. This work is aimed to investigate the correlation between TiO₂ nanostructure properties i.e.: crystallite size, surface area, band gap energy to obtain the optimum parameter for best performance as DSSC prototype. At this study, TiO₂ nanoparticles were synthesized via sol-gel process using titanium tetra-n-butoxide, ethanol, hydrochloric acid and deionized water with the ratio of (0.4 : 0.83 : 1 and 1.39) respectively upon sol preparation. The followed with multi-step calcinations to obtain anatase phase and post-hydrothermal process with various temperatures (100, 120, and 150 C). As comparison, TiO₂ of P25 Degussa was used and also assembled to make DSSC. The X-ray diffraction, BET (Brunauer-Emmett-Teller) and UV-Vis DRS (diffuse reflectance spectroscopy) tests were taken to characterize the samples. The performance of DSSC was investigated using open voltage circuit (Voc) measurement. The characterization results of synthesis powder shows indication at temperature 150°C was optimum process of post-hydrothermal with crystallite size 10.55 nm, surface area 95.38 m²/grams, and band gap energy 3.16 eV. Nevertheless, the open circuit voltage (V_OC) measurement reveals that the DSSC fabricated with post-hydrothermal at temperature process 120C provide the highest voltage (250 mV).