| 초록 |
A heterostructured photoanode including of a organized mesoporous TiO2 (om-TiO2) interfacial layer (IF layer), a 7 or 10μm-thick nanocrystalline TiO2 layer (NC layer), and a 2μm-thick mesoporous Bragg stack (meso-BS layer) was prepared onto a FTO glass via spin coating and doctor-blade method. An om-TiO2 layer fabricated via a sol-gel process, where a poly(vinyl chloride)-g- poly(oxyethylene methacrylate) (PVC-g-POEM) graft copolymer is used as a structure-directing agent showed a high porosity, transmittance and interconnectivity. The meso-BS layer with large pores is fabricated by deposition of om-TiO2 and colloidal SiO2 (col-SiO2) layers alternatively. DSSCs fabricated with the heterostructured photoanode and a polymerized ionic liquid (PIL) which is solide state electrolyte showed an energy conversion efficiencies of 6.6% at 100 mW/cm2, one of the highest value reported and much larger than DSSCs prepared with only a IF/NC layer (6.0%) or a NC layer (4.5%). Those Improvements are attributed to the improved light transmittance, decreased interfacial resistance at the electrode/electrolyte, and better electrolyte infiltration. |
