▎ 摘　　要

The use of graphene to bridge TiO2 particles in the photoanode of dye-sensitized solar cell for reduced electrical resistance has been investigated. The difficulty in dispersing graphene in TiO2 paste was overcome by first dispersing graphene oxide (GO) into the TiO2 paste. The GO was then reduced to graphene after the sintering of TiO2. This is shown through transmission electron microscopy and X-ray photoelectron spectroscopy analysis. Cell performance was evaluated using a solar simulator, incident photon to electron conversion efficiency, intensity modulated photocurrent/photovoltage spectroscopy under blue light, and electrochemical impedance spectroscopy. Depending on the amount of graphene in the photoanode, the cell performance was enhanced to different degrees. A maximum increase of 11.4% in the cell efficiency has been obtained. In particular, the inclusion of graphene has reduced the electron diffusion time by as much as 23.4%, i.e. from 4.74 to 3.63 ms and increased the electron lifetime by as much as 42.3%, i.e. from 19.58 to 27.85 ms. Copyright (C) 2014 John Wiley & Sons, Ltd.