TiO2 nanoparticles and nanowires were synthesized via a hydrothermal process and used to prepare composite photoanodes for dye-sensitized solar cells. The TiO2 nanoparticles had anatase and rutile phases, while the TiO2 nanowires existed in the TiO2(B), anatase, or rutile phase, depending on the post-calcination temperature. Measurement of the photovoltaic performance by a solar simulator showed that the composite photoanodes prepared from TiO2 nanoparticles and nanowires displayed superior light-to-electricity conversion efficiencies compared to those made solely of nanoparticles or of nanowires. Furthermore, all anatase-phase TiO2 nanoparticle/nanowire composites gave higher conversion efficiencies than did anatase nanoparticle/TiO2(B) nanowire composites. The highest conversion efficiency was found for the composite photoanode made of 90 wt% anatase TiO2 nanoparticles and 10 wt% anatase TiO2 nanowires.

Keywords: Anatase, TiO2(B), Nanoparticles, Nanowires, Dye-sensitized solar cell.