Niobium-Doped Titanium Dioxide Nanoparticles For Electron Transport Layers In Perovskite Solar Cells

Nb-doped TiO2 nanoparticles with different doping concentrations, varied from 0 to 2.7 mol.%, were prepared by the sol-gel method followed by thermal treatment. The obtained nanoparticles were used to fabricate a series of electron transport layers for constructing perovskite solar cells (PSCs). The prepared layers were characterized using X-ray diffraction and optical transmission measurements. The effects of Nb doping concentration in TiO2 layers on the optical absorption behavior, the morphology and charge carrier dynamics were studied. A series of PSCs, based on the developed electron transport layers was fabricated and examined. It was found that PSC fabricated with 2.7 mol.% Nb content TiO2 electron transport layer have shown up to 19 % improvement of a power conversion efficiency compared to that, based on an undoped TiO2 layer.