A sensitizer incorporating a heavily alkylated surface blocking indolizine donor exhibits excellent light absorption and diminished recombination rates in dye-sensitized solar cells (DSCs). DSC device efficiencies (up to 8%) using either I-/I-3(-) or Co(bpy)(3)(2+/3+) redox shuttles were obtained, which compare favourably to the known excellent surface coverage co-sensitization dye, D35.