Abstract
Abstract Nickel oxide (NiO) is one of the very few p-type semiconducting oxides, the study of which is gaining increasing attention in recent years due to its potential applicability in many emerging fields of technological research. Actually, a growing number of scientific works focus on NiO-based electrochromic devices, high-frequency spintronics, fuel cell electrodes, supercapacitors, photocatalyst, chemical/gas sensors, or magnetic devices, among others. However, less has been done so far in the development of NiO-based optical devices, a field in which this versatile transition metal oxide still lags in performance despite its potential applicability. This review could contribute with novelty and new forefront insights on NiO micro and nanostructures with promising applicability in optical and optoelectronic devices. As some examples, NiO lighting devices, optical microresonators, waveguides, optical limiters, and neuromorphic applications are reviewed and analyzed in this work. These emerging functionalities, together with some other recent developments based on NiO micro and nanostructures, can open a new field of research based on this p-type material which still remains scarcely explored from an optical perspective, and would pave the way to future research and scientific advances.
Highlights
Among the very few p-type metal oxides, nickel oxide (NiO) stands out as one of the most promising candidates in diverse forefront fields of research owing to its singular physico-chemical properties
Recent progress on emerging optical and optoelectronic devices based on Nickel oxide (NiO) are reviewed in this work
Apart from the well-known use of this material in electrochromic devices and smart windows, where NiO is of prime choice, as well as a hole injector layer in emerging photovoltaic devices, less has been done so far in the development of NiO based optical devices
Summary
Among the very few p-type metal oxides, nickel oxide (NiO) stands out as one of the most promising candidates in diverse forefront fields of research owing to its singular physico-chemical properties. The results showed resistivity values in a range between 80 and 200 Ω/cm as a function of the film thickness, measured using a van der Pauw configuration These films were confirmed to have p-type conductivity, with a carrier concentration around 1017 cm−3 and mobility close to 0.1 cm2/Vs. Following a similar procedure, Diao et al [7], synthesized Li doped NiO thin films with different annealing temperatures and times by a modified spray method. The origin of the p-type conductivity of NiO is related to the formation of interstitial oxygen [9, 10] and the inherent nickel deficiency, which motivates its extended use as hole transport material in optoelectronic devices. Recent scientific works reporting on the promising applicability of NiO in light emitting diodes and lighting devices, optical resonators, waveguides, saturable absorbers, and neuromorphic applications, where dimensions, morphology, and composition, play a key role, are reviewed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
