title: Multifunctional organized mesoporous tin oxide films templated by graft copolymers for dye-sensitized solar cells.
abstract: The synthesis of organized mesoporous SnO2 films with high porosity, larger pores, and good interconnectivity, obtained by sol-gel templating with an amphiphilic graft copolymer, poly(vinyl chloride)-graft-poly(oxyethylene methacrylate), is reported. An improved performance of dye-sensitized solar cells (DSSCs) is demonstrated by the introduction of a 400 nm thick organized mesoporous SnO2 interfacial (om-SnO2 IF) layer between nanocrystalline TiO2 (nc-TiO2 ) and a fluorine-doped tin oxide substrate. To elucidate the improved efficiency, the structural, optical, and electrochemical properties of the devices were characterized by SEM, UV/Vis spectroscopy, noncontact 3D surface profilometry, intensity-modulated photocurrent/voltage spectroscopy, incident photon-to-electron conversion efficiency, and electrochemical impedance spectroscopy measurements. The energy-conversion efficiency of the solid polymerized ionic liquid based DSSC fabricated with the om-SnO2 IF/nc-TiO2 photoanode reached 5.9% at 100 mW cm(-2) ; this is higher than those of neat nc-TiO2 (3.5%) and organized mesoporous TiO2 interfacial/nc-TiO2 layer (5.4%) photoanodes. The improved efficiency is attributed to the antireflective property, cascadal energy band gap, good interconnectivity, and high electrical conductivity of the om-SnO2 IF layer, which results in enhanced light harvesting, increased electron transport, reduced charge recombination, and decreased interfacial/internal resistance.
authors.affiliation: Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749 (South Korea), Fax: (+82) 2-312-6401.
authors.forename: Jung Tae
authors.initials: JT
authors.lastname: Park
authors.forename: Sung Hoon
authors.initials: SH
authors.lastname: Ahn
authors.forename: Dong Kyu
authors.initials: DK
authors.lastname: Roh
authors.forename: Chang Soo
authors.initials: CS
authors.lastname: Lee
authors.forename: Jong Hak
authors.initials: JH
authors.lastname: Kim
mesh_terms: D004396:Coloring Agents / Q000737:chemistry*; D011211:Electric Power Supplies; D008958:Models, Molecular; D008968:Molecular Conformation; D058105:Polymerization; D011109:Polymethacrylic Acids / Q000737:chemistry*; D011145:Polyvinyls / Q000737:chemistry*; D016062:Porosity; D012993:Solar Energy; D017971:Tin Compounds / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry
chemical_list: D004396:Coloring Agents; D011109:Polymethacrylic Acids; D011145:Polyvinyls; D017971:Tin Compounds; C585966:poly(vinyl chloride)-g-poly(oxyethylene methacrylate); C009495:titanium dioxide; D014025:Titanium; C045358:stannic oxide
keywords: dye-sensitized solar cells; interfaces; photochemistry; polymers; sol-gel processes; tin