Oxygen Vacancy Induced Room-Temperature Metal–Insulator Transition in Nickelate Films and Its Potential Application in Photovoltaics

摘要: Oxygen vacancy is intrinsically coupled with magnetic, electronic, and transport properties of transition-metal oxide materials directly determines their multifunctionality. Here, we demonstrate reversible control oxygen content by postannealing at temperature lower than 300 °C realize the metal–insulator transition in epitaxial NdNiO3 films. Importantly, over 6 orders magnitude resistance modulation a large change optical bandgap are demonstrated room without destroying parent framework changing p-type conductive mechanism. Further study revealed that vacancies stabilized insulating phase universal for perovskite nickelate Acting as electron donors, not only stabilize temperature, but also induce magnetization ∼50 emu/cm3 due to formation strongly correlated Ni2+ t2g6eg2 states. The opening an order larger t...