Chemical synthesis of nonstoichiometric NiOx nanoparticles using different nickel salts and application as an additive or interface layer in photovoltaic devices

The stoichiometric nickel oxide is an insulator while it becomes a p-type semiconductor with the presence of divalent and trivalent states. Here nonstoichiometric nanoparticles (NiO${}_{x}$NPs) were synthesized via chemical route using two different starter salts; chloride hexahydrate nitrate hexahydrate. investigated by X-ray diffraction transmission electron microscopy, scanning to determine crystal structure, morphology, particle size. effect salts in reaction formation NiO${}_{x\ }$nanoparticles observed for first time literature. Because high uniformity stability, nitrate-based inks employed as additives interface layers planar perovskite solar cells, two-step deposition regular (n-i-p) one-step antisolvent washing method inverted (p-i-n) configurations. Photovoltaic performances improved case NiO${}_{x}$ applied layer between P3HT Ag cells both additive sol-gel based HTL cells.