A seeding method to synthesize aggregate scattering titanium oxide by oriented attachment network titanium oxide as a seed for dye-sensitized solar cells

In this paper, seeding method is used to synthesize the random aggregate scattering TiO₂ (OAS) by oriented attachment particles (OA S2) as seeds. The OAS process has pure anatase phase and high surface area (205 m² g^-1). Its film shows rough surface and larger void spaces due to random aggregate particle, but there is no any crack over large area in the OAS film. Form the UV-vis transmittance spectra, the OAS film is opaque and able to diffuse visible light with transmittance less than 60% of incident light in 550 nm. The photovoltaic performance of dye-sensitized solar cells make of the double layer OA S2 + OAS exhibits higher JSC than the devices made of single layer OA S2. The reason for the higher JSC can be further proved by IPCE. The OAS film also shows lower charge transport resistance and higher electron lifetime contrasted with the commercial scattering particle CCIC 400. A higher light-to-electricity power conversion efficiency of 7.06% is achieved by applying the double layer OA S2 + OAS.