An adaptable strategy to introduce different anchors to [Ru(N⁁N)2(C⁁N)]+ dyes is described; use of a phosphonic acid anchor on NiO leads to p-type DSCs with JSC = 3.38 mA cm−2 and PEC of 0.116%.

A comparison of the performances of p-type dye sensitized solar cells (DSCs) sensitized by three cyclometallated ruthenium(II) dyes differing in their anchoring domains is presented. The dyes are [Ru(bpy)2(H1)] (H31 = (4-(2phenylpyridin-4-yl)phenyl)phosphonic acid) and the salts [ n Bu4N][Ru(bpy)2(1)] and [Ru(bpy)2(H2)][PF6] (H22 = (4-(2-phenylpyridin-4-yl)phenyl)carboxylic acid). DSCs were fabricated with FTO/NiO working electrodes and either an I-/I3-/MeCN or I-/I3-/MeCN:EtCN (3:1 by volume) electrolyte. The results confirm the higher performance of dyes with a phosphonate versus carboxylic acid anchor, and reveal that [Ru(bpy)2(H1)] (JSC = 3.24 mA cm-2 and η = 0.116%) performs better than [Ru(bpy)2(1)]-. Electrochemical impedance spectroscopy (EIS) shows that a DSC with [Ru(bpy)2(H1)] offers the lowest transport and recombination resistances and the shortest hole lifetime and diffusion length.