“…Ruthenium and osmium complexes have shown the best photovoltaic performance in terms of both conversion yield and long-term stability [12][13][14][15]. In particular, these performances are achieved when these metals are coordinated with polypyridyl complexes, thanks to an overall broad absorption spectrum ( Up to now the cis-bis(isothiocyanato) bis(2,2'-bipyridil-4,4'-dicarboxilato ruthenium (II) (commonly named N3, Figure 1.9, on the left) and ditetrabutylammonium,cis-bis(isothiocyanato)bis(2,2'-bipyridil-4,4'-dicarboxilato ruthenium (II), commonly named N719 (on the right), show the best photovoltaic performances, which result to be 10.4% [24] and 11.18% [25].…”