Chemical passivation of the perovskite layer and its real-time effect on the device performance in back-contact perovskite solar cells

The back-contact architecture for perovskite solar cells (PSCs) offers the possibility of positioning both electrodes on one side of the absorber layer and shining light directly on the perovskite photoactive layer. This helps us to avoid the occurrence of transmission losses caused by the charge collecting transparent conductive oxide electrode in the conventional sandwich structure for PSCs. The back-contact device architecture is also useful for conducting fundamental studies as it has an exposed photoactive area, permittingin situmeasurements on the effects of chemical treatment, passivation, and annealing. A successful application of back-contact PSCs in studying the effect of chemical passivation of the perovskite photo-absorber layer trap states with pyridine and its influence on the device performance have been studied. The real-time effect of pyridine vapor treatment on the device performance is visualized by monitoring the maximum power output of the devices under operation conditions. The device performance enhancement by similar to 12% owing to the surface passivating effect of pyridine is demonstrated.