Prof Paik- Lecture- Dr Sudha技术知识.ppt

Driving Force for Dye Regeneration 0.6 M BMII, 0.1 M LiI, 0.1 M I2 and 0.5 M t-BP in acetonitrile and methoxypropionitrile (7:3 vol. ratio) (1) (2) (3) (4) vacuum EF VB CB I-/I3- TiO2 Voc ΔG01 ΔG02 ΔG03 ΔG04 HOMO (1) HOMO (2) HOMO (3) HOMO (4) ΔG02 ΔG01 ΔG03 ΔG04 TiO2 redox HOMO EF LUMO Dye ΔG0 A lower limit for the regeneration time is given by diffusion-limited kinetics If electrolyte contains excess electron donor ( 0.1 M), diffusion is not a matter of limitation (non-viscous electrolyte system) 0.5 ~ 0.6 eV driving force (ΔG0) is needed for dye regeneration (Ru-dye I-/I3- system) J.N. Clifford et al., J. Phys Chem C, 2007, 111, 6561 Panchromatic Sensitizer General Sensitizer Panchromatic Sensitizer Maximum absorption around one peak - Absorption all the light from the visible to the near infrared (NIR) domain. P-5 N-719 N-749 a P5 dye P5 dye P5 dye N719 dye N719 dye N749 dye Carbon EPMA Ru EPMA TiO2 film Ru EPMA 5 ?m b 5 ?m 5 ?m N.-G. Park et al., Nat. Mater., 8, 665 (2009) Panchromatic DSSC Selective positioning of three different dyes IPCE spectrum of the selectively positioned dyes P5 (9 ?m) Bare (16 ?m) N749 (7 ?m) N719 (9 ?m) Cocktail Sensitizer J. Yum et al., Chem. Commun., 4680 (2007) Dye A Dye B Electrolyte FTO η : 7 % η : 4.23 % JK2 + SQ1 η : 7.38 % thickness : 7 + 4 μm Energy Relay Dye F?RSTER RESONANT ENERGY TRANSFER (FRET) D*+ A→ D+ A* J. Yum et al., Angew. Chem. Int. Ed., 48, 9277 (2009) Energy Relay Dye B.E. Hardin et al., Nature Photonics 3, 406 (2009) FRET involves dipole–dipole coupling of two chromophores, known as the donor and acceptor, through an electric field. An excitation of the donor, or in our case the ERD, can be transferred non-radiatively through the field to the acceptor, or SD, if there is overlap between the emission spectrum of the donor and the absorption spectrum of the acceptor. Efficient energy transfer over 3–8 nm can be achieved with strong spectral overlap and high donor emission efficiencies, f