title: Hydroxamate anchors for improved photoconversion in dye-sensitized solar cells.
abstract: We present the first analysis of performance of hydroxamate linkers as compared to carboxylate and phosphonate groups when anchoring ruthenium-polypyridyl dyes to TiO2 surfaces in dye-sensitized solar cells (DSSCs). The study provides fundamental insight into structure/function relationships that are critical for cell performance. Our DSSCs have been produced by using newly synthesized dye molecules and characterized by combining measurements and simulations of experimental current density-voltage (J-V) characteristic curves. We show that the choice of anchoring group has a direct effect on the overall sunlight-to-electricity conversion efficiency (η), with hydroxamate anchors showing the best performance. Solar cells based on the pyridyl-hydroxamate complex exhibit higher efficiency since they suppress electron transfer from the photoanode to the electrolyte and have superior photoinjection characteristics. These findings suggest that hydroxamate anchoring groups should be particularly valuable in DSSCs and photocatalytic applications based on molecular adsorbates covalently bound to semiconductor surfaces. In contrast, analogous acetylacetonate anchors might undergo decomposition under similar conditions suggesting limited potential in future applications.
authors.affiliation: Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, USA.
authors.forename: Timothy P
authors.initials: TP
authors.lastname: Brewster
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Konezny
authors.forename: Stafford W
authors.initials: SW
authors.lastname: Sheehan
authors.forename: Lauren A
authors.initials: LA
authors.lastname: Martini
authors.forename: Charles A
authors.initials: CA
authors.lastname: Schmuttenmaer
authors.forename: Victor S
authors.initials: VS
authors.lastname: Batista
authors.forename: Robert H
authors.initials: RH
authors.lastname: Crabtree
mesh_terms: D004396:Coloring Agents / Q000737:chemistry*; D011211:Electric Power Supplies; D006877:Hydroxamic Acids / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D055668:Photochemical Processes; D012993:Solar Energy
chemical_list: D004396:Coloring Agents; D006877:Hydroxamic Acids; D009942:Organometallic Compounds