Efficient and hysteresis-less pseudo-planar heterojunction perovskite solar cells fabricated by a facile and solution-saving one-step dip-coating method

Rough dense sol-gel-derived titanium dioxide (TiO2) electron-transport layers (ETLs) and smooth organolead halide perovskite (PVK) films for pseudo-planar heterojunction perovskite solar cells (P-PH PVKSCs) were fabricated by a facile one-step dip-coating method. The highly compact TiO2 ETLs and uniform PVK films endow the device a high power conversion efficiency (PCE) of over 11%, which was nearly identical to that of a reference device (12%) fabricated by conventional spin-coating. Furthermore, the device showed no pronounced hysteresis when tested by scanning the voltage in a forward and backward direction, showing the potential of facile and waste-free dip-coating in replacing of spin-coating for large area perovskite solar cells preparation. Lastly, the hysteresis was compared and discussed and models regarding the abnormal hysteresis, roll-over and current peak phenomena were proposed as well. (C) 2016 Elsevier B.V. All rights reserved.