Reasoning the Change in Device Parameters with Deposition Power of NiOx for Low-Dimensional Perovskite Solar Cells

Low-dimensional perovskites have gained attention due to their excellent stability, but still they struggle with achieving competent efficiency. Solar cells' performance depends not only on the absorber layer but also on the transport layer and contacts. Transport layers are responsible for charge separation in perovskite solar cells (PSCs) and hence play a crucial role in the determination of device parameters which collectively give us the device efficiency. Transport layers specific to low-dimensional perovskites have not been rigorously studied and thus remain an open problem to be pondered upon. Here, we demonstrate the effect of modification of transport layer properties on PSCs by linking the properties of NiOx to the device parameters obtained by current-voltage measurements. The lowdimensional perovskite (PEA)2MA4Pb5I16 is used as an absorber for the fabricated PSCs. The deposition power for NiOx during the pulsed DC magnetron sputtering is varied by keeping all the other parameters the same. The power used for deposition is 60W, 75W, and 90W at 200 °C substrate temperature and base pressure of 1e-6 mbar. The champion device is obtained at 75W deposition power for NiOx, having an efficiency of 10.52%. Improving device parameters by tuning the deposition parameters for NiOx cumulatively increases the efficiency.