Figure 2
From: Improving the performance of dye-sensitized solar cells with TiO2/graphene/TiO2 sandwich structure
SEM images of TiO 2 nanoparticles. (a) Nanoparticles in structures of DSSCs. (b) Sample 1. (c) Sample 2. (d) Sample 3.
Figure 2 | Nanoscale Research Letters