Sequential Deposition of CH₃NH₃PbI₃ on Planar NiO Film for Efficient Planar Perovskite Solar Cells

Abstract

The new emerging organometal trihalide perovskite holds great potential for high-efficiency, low-cost solar cells because of its high solar to electricity conversation efficiency (>16%) achieved within 4 years of research and its low-temperature solution processing. In this Letter we introduce NiO as the hole-collecting and -conducting layer in perovskite solar cells. Through a modified sequential deposition strategy, we successfully fabricated high-quality CH3NH3PbI3 onto a planar NiO layer and built a planar inverted ITO/NiO/CH3NH3PbI3/PCBM/Al photovoltaic device. A device efficiency of 7.6% was achieved with an impressively high open-circuit voltage (Voc) of 1.05 V. Our study demonstrates the potential application of a deep work function NiO layer for perovskite solar cells.