A new photoanode architecture of dye sensitized solar cell based on ZnO nanotetrapods with no need for calcination

We introduce a photoanode architecture in dye sensitized solar cell comprising building blocks of ZnO nanotetrapods with a mean arm diameter of 40 nm and arm lengths of 500-800 nm. This photoanode features a decent roughness factor up to 400, good network forming ability and limited electron-hopping interjunctions. Even without calcination, a power conversion efficiency up to 3.27% (under 100 mW cm(-2)) has been achieved at a film thickness of 31.2 mu m. The avoidance of the calcination step is an outstanding feat for flexible solar cells. We have also employed impedance spectroscopy to interpret the solar cell performance features. (C) 2009 Elsevier B.V. All rights reserved.