SIMS studies on photodegradation of fullerene derivatives

State of the art organic photovoltaic devices (OPV) have achieved the power conversion efficiency over 10%. Environmentally friendly, cheap in production, lightweight and flexible could soon compete with solar cells created based on silicon technology. The problem to be solved before OPVs become commonly used is their limited lifetime. In order to do so we need a deeper understanding of the photodegradation process of donors and acceptors constituting the OPV. Changes in the chemical composition of degraded organic materials can be traced with various techniques, among them the Secondary Ion Mass Spectrometry (SIMS) is one of the most versatile method providing information about the chemical composition of the surface as well as the composition variation within the active layer of solar cells. In this talk I will present a short summary of our recent results of the studies on photodegradaton of fullerene derivatives, commonly used as acceptors in OPVs.