Enhanced photovoltaic performance of dye-sensitized solar cells (DSSCs) using graphdiyne-doped TiO2 photoanode

As a novel two-dimensional material consisting of sp- and sp2-hybridized carbon atoms, graphdiyne (GD) shows great potentials in the field of electric and material science. In particular, the performance is reported to be significantly improved for GD-involved optoelectronic devices due to its excellent electronic properties. Herein, to facilitate the charge transfer process and further improve the photo-to-electricity conversion efficiency (PCE) for dye-sensitized solar cells (DSSCs), for the first time we introduced GD in the TiO2(P25)-based photoanodes of DSSCs, resulting in GD-doped TiO2 photoanodes. It was shown that the overall performance of the GD-doped cell is significantly enhanced due to the higher dye adsorption amount, faster electron transfer and lower recombination, compared to that of the undoped DSSC. Furthermore, the optimum GD doping amount (weight percent, wt%) was determined. Thus, the DSSC involving P25-0.6 wt% GD photoanode achieved the best PCE of 8.03%, which increased by 26.5% comparing with that of pure P25 film-based cell.