Rare
earth oxides (REOs) are deemed important from both industrial
implementation and research insight perspectives. One of the most
conspicuous attributes of REOs is sensing, which contributes significantly
to the development of diversified and robust systems of sensors and
detector devices. However, there has not been any organized review
that has pointed out critical insights from the sensor, detector,
and electronic device perspectives that can invoke further studies
to investigate the prospective and commercially relevant areas to
date. To address this limitation, this review undertakes a focused
report approach. From this concise yet comprehensive review, it has
been prominent that the most significant contributions to the sensing
and detecting fields by the REOs are in electrochemical, temperature,
humidity, radiation, gas, and biosensors. Moreover, in terms of electronic
device development, REOs have had a significant impact on memory devices,
metal oxide semiconductors, dielectric materials, capacitors, energy
storage devices, and so on. Furthermore, one of the key findings of
the study is that the REOs have flexible doping (e.g., Er3+, Yb3+, Y3+, etc.) capability combined with
other host materials such as HfO2 film, SiO2 stacks, TiO2, SnO2 nanostructures, etc., which
will likely make REO-based electrochemical sensor and biosensor development
the most promising sector in the coming years. Despite the impressive
aspects, biocompatibility issues in several biological and biomedical
systems along with the hygroscopic nature of REOs in electronic devices
remain as concerns. However, these issues can be addressed by the
advancement of intricate technologies such as targeted manipulation
of the electronic configuration of REOs, multifarious doping experiments
to obtain alternative mechanisms, etc. to obtain superior biocompatibility,
and device development systems that are noninvasive to the environment.
From the commercialization front, memory devices and energy storage
devices will be the focusing points for large-scale investors due
to improved mechanical (i.e., Young’s modulus, intrinsic stress,
etc.) and electrical (i.e., high dielectric constant, resistivity,
relative permittivity, etc.) properties, while REO-based metal oxide
semiconductor and capacitor development is likely to be research-oriented
for the next few years before making the eventual move to futuristic
applications at a large industrial scale. In short, this review reports
a substantial number of relevant studies that will pave the way for
further experimental and computational investigations on REOs and
their sensor, detector, and electronic device aspects.
