Since the demonstration of efficient hybrid photovoltaic devices using CdSe/P3HT, a number of different QD/polymer molecular solar cells have been investigated. However, considerably less attention has been paid to the photo-induced processes occurring in these devices, in particular the strong dependence that device efficiencies show upon QD concentration. This study aims to shed more light on this dependence by monitoring these processes occurring at the QD/polymer interface, namely, exciton formation, charge separation and undesired charge recombination.