External quantum efficiency measurements used to study the stability of differently deposited perovskite solar cells

The instability exhibited by perovskite solar cells when exposed to the environment under illumination is one of the major obstacles for the entry of perovskite technology in the photovoltaic market. In this work, we use the external quantum efficiency (EQE) technique to study the photoinduced degradation of two types of solar cells having CH3NH3PbI3 as an absorber layer: one deposited by spin coating with an n-i-p architecture and the other deposited by evaporation with an inverted p-i-n structure. We also study the effect of different encapsulants to protect the cells against atmospheric agents. We find that EQE provides information regarding the areas of the cell most susceptible to degr…