Nitrogen-Doped Graphene/Platinum Counter Electrodes for Dye-Sensitized Solar Cells
journal contributionposted on 17.12.2014, 00:00 by Chin-An Lin, Chuan-Pei Lee, Shu-Te Ho, Tzu-Chiao Wei, Yu-Wen Chi, K. P. Huang, Jr-Hau He
Nitrogen-doped graphene (NGR) was utilized in dye-sensitized solar cells for energy harvesting. NGR on a Pt-sputtered fluorine-doped tin oxide substrate (NGR/Pt/FTO) as counter electrodes (CEs) achieves the high efficiency of 9.38% via the nitrogen doping into graphene. This is due to (i) the hole-cascading transport at the interface of electrolyte/CEs via controlling the valence band maximum of NGR located between the redox potential of the I–/I– redox couple and the Fermi level of Pt by nitrogen doping, (ii) the extended electron transfer surface effect provided by large-surface-area NGR, (iii) the high charge transfer efficiency due to superior catalytic characteristics of NGR via nitrogen doping, and (iv) the superior light-reflection effect of NGR/Pt/FTO CEs, facilitating the electron transfer from CEs to I3– ions of the electrolyte and light absorption of dye. The result demonstrated that the NGR/Pt hybrid structure is promising in the catalysis field.