Effects of Hole Transport Layer Thickness on Photovoltaic Performance of Perovskite Solar Cell

We demonstrate effects of thickness of liquid-crystalline based hole transport layer (HTL) on photovoltaic performance of perovskite solar cell (PSC). A 70 nm thick HTL resulted in a device achieving a power conversion efficiency (PCE) of 9.8% under reverse bias scanning. Increasing the liquid-crystalline based HTL thickness to 100 nm improved device performance, yielding a PCE of 11.4%, indicating enhanced interfacial contact and more effective coverage of HTL over the CH3NH3PbI3 perovskite absorber. Notably, the hysteresis index decreased with increasing the liquid-crystalline based HTL thickness, suggesting mitigation of charge accumulation at the interfacial layers and reduction of the hysteresis phenomena in PSCs.