“…[12,[15][16][17][18][19][20][21] For instance, rate constants (kct, subscript ct stands for charge transfer; it can be turned into subscripts cs and cr standing for charge separation and charge recombination, respectively) for photoinduced charge transfer (CT) reactions occurring in P3HT-PCBM reveal the potential of such materials in the construction of efficient DSSCs. Based on quantum chemistry methods, these kct have been demonstrated [22] to be tunable by a few parameters so that the power conversion efficiency may be increased; [23][24][25] which highlights, in fact, the importance of theoretical developments for the understanding and design of DSSCs with improved efficiency. [26] At the molecular level, blends such as P3HT-PCBM are classified into the so called bulk heterojunctions [27] (BHJs), where the donor and acceptor moieties are not covalently connected, and molecular heterojunctions [28] (mHJs) with covalently linked donor and acceptor.…”