Effect of V-incorporated NiO Hole Transport Layer on the Performance of Inverted Perovskite Solar Cells

Organic-inorganic hybrid perovskite solar cells have resulted in tremendous interest in developing future generation solar cells due to high efficiency exceeding 25%. For inverted type perovskite solar cells, the hole transporting layer plays a crucial role in improving the efficiency and stability of the perovskite solar cells by modifying band alignment, electric conductivity, and interfacial recombination losses. Here, vanadium doped NiO is selected as a hole transporting layer to study the impact of V dopant on the optoelectronic properties of NiO and the photovoltaic performance. The prepared materials are characterized using XRD, SEM, TEM, and XPS. TEM micrograph confirms that p-type materials have small spherical dot structure. The V-doped NiO used as a hole-extraction layer can be prepared by the simple solvothermal decomposition method. The presence of V in the NiO layer has an influence on the conductivity of the NiO layer. In addition, synthesized p-type material can be used to fabricate relatively low processing temperature has the advantage of a wide choice of transparent conductive oxide substrate. As a result, inverted type planar perovskite solar cell incorporating of V:NiO hole-transport layer is improved power conversion efficiency. The photovoltaic property of the prepared solar cell is measured under AM 1.5 G simulated light and the results are listed in Table 1. The photo-current density is 21.09 mA/cm², open-circuit voltage is 1.04 V, and the fill factor is 0.63. As a result, the overall power conversion efficiency reaches 13.82%.