Microwave-assisted synthesis of Bi2Se3 /reduced graphene oxide nanocomposite as efficient catalytic counter electrodefordye-sensitized solar cell

Bi₂Se₃/reduced graphene oxide (rGO) composite was successfully synthesized by a facile microwave-assisted hydrothermal method and applied as a counter electrode for efficient dye-sensitized solar cells. By this means, the size and distribution of the formed Bi₂Se₃ nanoparticles onto a flexible graphene sheet were effectively controlled, which is crucial for achieving high electrocatalytic activity on I₃^? reduction. Mainly due to the homogeneous single-layer immobilization of Bi₂Se₃ nanoparticles on a graphene sheet with high density, BiG2 exhibited the highest catalytic activity and the lowest electrolyte diffusion resistance. Adye-sensitized solar cell with BiG2 as a counter electrode can yield 7.09% photoelectric conversion efficiency, which is comparable to that of the cell with a Pt-film counter electrode (6.23), exhibiting the application potential of BiG2 as a low cost non-Pt CE materials for DSSC.