Sensitization of TiO(2) by Phosphonate-Derivatized Proline Assemblies.
Surface electrochemical and photoelectrochemical measurements on ITO (In(2)O(3):Sn) or TiO(2) of two proline assemblies are reported. Surface coverage on ITO of Pbp-pra(Ru(II)b(2)m)-OH(PF(6))(2) and Bpb-pra(Ru(II)b(2)m)-OCH(3)(CF(3)CO(2))(2) are (1.5-2.4) x 10(-)(10) mol/cm(2), comparable to monolayer coverages of (1.5-2.5) x 10(-)(10) mol/cm(2) for [Ru(bpy)(2)(4,4'-(CO(2)H)(2)bpy)](PF(6))(2) and [Ru(bpy)(2)(4,4'-(PO(3)H(2))(2)bpy)](Br)(2). Incident photon-to-current conversion efficiency (IPCE) measured in Gräztel-type photovoltaic cells are sensitive to subtle structural differences in the assemblies. IPCE values for Pbp-pra(Ru(II)b(2)m)-OH(PF(6))(2) and Bpb-pra(Ru(II)b(2)m)-OCH(3)(CF(3)CO(2))(2) are 2% and <0.1%, which are compared to 23% for both [Ru(bpy)(2)(4,4'-(PO(3)H(2))(2)bpy)](Br)(2) and [Ru(bpy)(2)(4,4'-(CO(2)H)(2)bpy)](PF(6))(2) under the same conditions.
Trammell
Scott A.
SA
Department of Chemistry, University of North Carolina at Chapel Hill, CB# 3290, Chapel Hill, North Carolina 27599-3290.
Moss
John A.
JA
Yang
John C.
JC
Nakhle
Bassam M.
BM
Slate
Cheryl A.
CA
Odobel
Fabrice
F
Sykora
Milan
M
Erickson
Bruce W.
BW
Meyer
Thomas J.
TJ