A simple small molecule as an acceptor for fullerene-free organic solar cells with efficiency near 8%

A simple small molecule acceptor named DICTF, with fluorene as the central block and 2-(2,3-dihydro-3-oxo-1H-inden-1-ylidene) propanedinitrile as the end-capping groups, has been designed for fullerene-free organic solar cells. The new molecule was synthesized from widely available and inexpensive commercial materials in only three steps with a high overall yield of similar to 60%. Fullerene-free organic solar cells with DICTF as the acceptor material provide a high PCE of 7.93%.