Electron migration between inter and intra particles in the soft-template processed titania nanospheres and its influences in the photovoltaic performance of the dye-sensitized solar cells

In this paper, different sizes of Titanium dioxide (TiO₂) nanospheres were prepared with the aid of soft-template cetyltrimethylammonium bromide (CTAB) and polyethylene glycol (PEG M.W. 20,000) by using sol–gel method. The crystalline, morphological, and optical properties of synthesized TiO₂ materials were studied. The TiO₂ nanospheres of 1-TiO₂, 3-TiO₂, and 5-TiO₂ modified photoanode dye-sensitized solar cells (DSSCs) demonstrated the power conversion efficiency of 1.6, 5.9, and 7.4%, respectively, under standard AM 1.5 G illumination (100 mW cm⁻²). On increasing the amount of precursor during the synthesis, the particle size decreases but the efficiency of the synthesized materials increases. The higher efficiency exhibited by 5-TiO₂ based DSSC is mainly due to the inter- and intra-sphere connection of small nanoparticles, increased electron lifetime, and suppressed back electron transfer process. This work paves the way to find potential candidate to develop an efficient photoanode material with magnificent photovoltaic performance.