Since ancient times, plasmonic structural coloring has inspired humanity; glassmakers achieved vibrant colors by doping glass with metal nanoparticles to craft beautiful objects such as the Roman Lycurgus cup and stained glass. These lovely color filtering effects are a consequence of the resonant coupling of light and free electrons in metal nanoparticles, known as surface plasmons. Thanks to the continuing improvement of nanofabrication technology, the dimensions of nanoparticles and structures can now be precisely engineered to form “optical nanoantennas,” allowing for control of optical response at an unprecedented level. Recently, the field of plasmonic structural coloring has seen extensive growth. In this review, we provide an up-to-date overview of various plasmonic color filtering approaches and highlight their uses in a broad palette of applications. Various surface plasmon resonance modes employed in the plasmonic color filtering effect are discussed. We first review the development of the pioneering static plasmonic colors achieved with invariant optical nanoantennas and ambient environment, then we address a variety of emerging approaches that enable dynamic color tuning, erasing, and restoring. These dynamic color filters are capable of actively changing the filtered colors and carrying more color information states than the static systems. Thus, they open an avenue to high-density data storage, information encryption, and plasmonic information processing. Finally, we discuss the challenges and future perspectives in this exciting research area.

Bright, stable, linearly polarized, and high-purity single-photon emitters at room temperature are observed in SiN.

In this paper, we present a novel laser-induced oxidation procedure for in situ formation of nickel oxide nanoporous structures directly onto the nickel surface as a highly sensitive nonenzymatic glucose sensor. The formation of mesoporous nickel oxide is confirmed by field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction. Electrochemical properties of the pristine and laser-induced oxidized nickel (LIO-Ni) films were studied using cyclic voltammetry and electrochemical impedance spectroscopy. The unique three-dimensional mesoporous architecture of the oxide film on the LIO-Ni electrode resulted in a dramatic enhancement in electrochemical reduction/oxidation performance with a 10-fold increase in electrocatalytic activity for nonenzymatic glucose oxidation as compared to the pristine-Ni electrode. The LIO-Ni biosensor performance was successfully examined for the amperometric detection of glucose over a wide concentration range from 5 μM to 1.1 mM with a high linear sensitivity of 5222 μA mM −1 cm −2 . The limit of detection was obtained as low as 3.31 μM with a signal-tonoise ratio of 3. Furthermore, the LIO-Ni electrode showed outstanding long-term stability, reproducibility, and high selectivity in the presence of various interfering agents including uric acid, L-ascorbic acid, acetaminophen, glutamic acid, and citric acid. The demonstrated laser-induced oxidation process can be potentially adapted to the scalable manufacturing of a wide range of other easyto-use and robust metal oxide-based sensors for nonenzymatic biosensing applications.

This work describes the preparation, characterization and use of a nickel oxide/oxyhydroxide-printed carbon electrode as an efficient potentiometric phosphate sensor.