Giant molecule acceptors for high performance polymer solar cells

Giant molecule acceptors (GMAs) are composed of two or more narrow bandgap small molecule acceptors (SMAs) subunits connected by conjugated or non-conjugated linking units, which possesses the advantages of the SMAs with broad absorption, appropriate electronic energy levels and fixed molecular weight (with good photovoltaic performance reproducibility), and the polymerized SMAs (PSMAs) with good film-forming property and high morphology stability and photo-stability. So that the GMAs are promising for future commercial application in polymer solar cells (PSCs). Therefore, the GMAs have attracted great attention recently. In this review, we will briefly introduce the development of the narrow bandgap SMAs, especially the A-DA’D-A structured SMAs, and the PSMAs. Then we will focus on the recent research progress of the GMAs, including the synthetic method of GMAs and the effect of number of the SMA subunits on the photovoltaic performance of the GMAs. Finally, we present our perspectives and offer a concise outlook on the further advancement of the GMAs.