Efficient Perovskite Solar Cells Employing Inorganic Interlayers

In this work, inverted structure CH₃NH₃PbI₃ perovskite-based solar cells (PSCs) employing different inorganic metal oxides as hole-selective interlayers have been fabricated on ITO/NiO_x, ITO/VO_x and ITO/MoO_x substrates and exhibit power conversion efficiencies (PCEs) of 10.6±0.6 %, 11.7±0.5 % and 5.9±0.5 %, respectively. The metal oxide layers deposited on ITO glass modify the substrate work function, leading to open circuit voltages above 1.0 V. Moreover, solar cells fabricated on ITO substrates without any metal oxide layer achieve a high PCE of 11.5 %, indicating that PSCs can perform well with a single selective contact. The inverted structure PSCs, with or without the metal oxide interlayers, show only a weak hysteresis in the J-V measurements. Our work reveals that single selective contact PSCs with simplified device structures can be very efficient after optimization of each active layer, making them highly competitive with other types of thin film photovoltaic (PV) technologies.