A water-soluble metallophthalocyanine derivative as a cathode interlayer for highly efficient polymer solar cells

Abstract

A novel organic small molecule water-soluble poly-N-alkylpyridine substitued metallophthalocyanine derivative VOPc(OPyCH₃I)₈, namely 2,3,9,10,16,17,23,24-octakis-[N-methyl-(3-pyridyloxy)] vanadylphthalocyanine iodide (1 : 8), was synthesized and applied in polymer solar cells (PSCs). Notably, a power conversion efficiency (PCE) of 8.12% for the working area of 2 × 2 mm² and a PCE of 7.23% for the working area of 4 × 4 mm² have been achieved in the PSCs with this molecule as a cathode interlayer. They are comparable with the higher values of PCE of the PSCs reported currently, indicating that VOPc(OPyCH₃I)₈ is a new promising candidate as a good cathode interlayer for highly efficient PSCs.