Donor−Acceptor‐Functionalized Subphthalocyanines for Dye‐Sensitized Solar Cells

Abstract

AbstractBoron subphthalocyanines (SubPcs) are attractive as light harvesting materials in photovoltaic devices. Here we present the synthesis, optical and electrochemical properties, and device performances of a series of donor−acceptor‐functionalized SubPc derivatives incorporating a carboxylic acid for anchoring onto TiO2. Liquid‐ and solid‐state dye‐sensitized solar cells (DSCs) were prepared from three compounds, and a triad system consisting of two aniline donor moieties and a benzothiadiazole acceptor moiety was found to exhibit the highest power conversion efficiency (PCE) in the series (PCE=1.54 %; solid‐state device). The compounds were prepared by stepwise acetylenic coupling reactions. In addition, we present the synthesis and optical properties of a SubPc derivative incorporating three anilino‐substituted 1,1,4,4‐tetracyanobutadiene units, prepared by the [2+2] cycloaddition between three ethynyl units at the SubPc periphery and three tetracyanoethylene molecules followed by electrocyclic ring‐opening reactions.