M. Napari, T. Huq, T. Maity
Jan 17, 2020
Citations
0
Influential Citations
19
Citations
Journal
Journal name not available for this finding
Abstract
Nickel oxide (NiO) is one of the most studied transition metal oxides due to its versatile chemical and electronic properties, enabling it to be used in a wide variety of applications. In its stoichiometric form, NiO is an antiferromagnetic insulator, with resistivity up to 10 Ω cm. When Ni vacancies are introduced, the nonstoichiometric nickel oxide becomes a semiconductor. Both theoretical and experimental results have shown that in oxygen-rich conditions the formation energy of the Ni vacancies is the lowest for all defects, leading to p-type conduction. With a wide band gap (3.5-4.0 eV) and high work function (4.8-6.7 eV), depending on the crystalline structure, composition, and the processing of the films, nickel oxide has gained interest especially in optoelectronics, where it is used as a hole transport/injection layer for photovoltaics and light-emitting diodes. Nickel oxide thin films have also been shown to have great potential across a wide range of electronics applications from gas sensors to thin film transistors and resistive switching random access memory (ReRAM) devices. These include flexible electronic devices, in which nickel oxide has been shown to be stable after exposure to tensile or compressive strains. Many of these applications rely on nickel oxide being nonstoichiometric, which has a significant effect on the electrical properties. The antiferromagnetic nature of the NiO has made it a common material in spintronics research, for example, in the fabrication of spin valves and next-generation memory Received: 18 October 2019 Revised: 8 November 2019 Accepted: 28 November 2019