Chemical Bath Deposition of NiOx-NiSO4 Heterostructured Hole Transport Layer for Perovskite Solar Cells

Herein, the scalable chemical bath deposited NiO x -NiSO 4 heterostructured films are reported as the efficient hole transport layers (HTLs) in perovskite solar cells. The NiO x -NiSO 4 films show excellent hole extraction ability and reduce interfacial charge recombination in solar cell devices. By using NiO x -NiSO 4 HTLs, a high power conversion efficiency of 20.55% is obtained, which is about 12.23% greater than that of the pure NiO x transport layer. This study provides a simple solution-processing route toward the large-area production and fabrication of full inorganic transport layers for perovskite photovoltaics.