Yoon‐Bong Hahn

Using ZnO nanonails, a hydrazine electrochemical sensor has been fabricated, for the first time, which showed a high and reproducible sensitivity of 8.56 microA cm(-2) microM(-1) with a response time less than 5 s, a linear range from 0.1 to 1.2 microM and a correlation coefficient of R = 0.999. The limit of detection (LOD), based on the S/N ratio, was estimated to be 0.2 microM.

Abstract There is a major challenge to attach nanostructures on to the electrode surface while retaining their engineered morphology, high surface area, physiochemical features for promising sensing applications. In this study, we have grown vertically-aligned ZnO nanorods (NRs) on fluorine doped tin oxide (FTO) electrodes and decorated with CuO to achieve high-performance non-enzymatic glucose sensor. This unique CuO-ZnO NRs hybrid provides large surface area and an easy substrate penetrable structure facilitating enhanced electrochemical features towards glucose oxidation. As a result, fabricated electrodes exhibit high sensitivity (2961.7 μA mM −1 cm −2 ), linear range up to 8.45 mM, low limit of detection (0.40 μM), and short response time (<2 s), along with excellent reproducibility, repeatability, stability, selectivity, and applicability for glucose detection in human serum samples. Circumventing, the outstanding performance originating from CuO modified ZnO NRs acts as an efficient electrocatalyst for glucose detection and as well, provides new prospects to biomolecules detecting device fabrication.

Well-aligned ZnO nanorod and nanopencil arrays were synthesized in a high density on ZnO/Si substrate by a low-temperature aqueous solution technique. Detailed structural characterizations revealed that the as-synthesized nanorods and nanopencils were single crystalline, with a hexagonal phase, and with growth along the [0001] direction. The room-temperature photoluminescence spectra showed a strong ultraviolet emission at 381 nm, a weak blue band at 460 nm, and a broad green emission at 580 nm. A detailed growth mechanism has been proposed for the formation of nanorods and nanopencils based on the different crystallographic habits of wurtzite hexagonal ZnO.

Unique and fascinating features of metal oxide nanostructures (MONs) have attracted considerable attention in recent years because without much effort, the MONs can be grown in many different nanoscale forms, thus allowing various novel devices of chemical and biological sensing to be fabricated. To improve the sensors performance by tailoring the properties of MONs through engineering of morphology, particle size, effective surface area, functionality, adsorption capability and electron-transfer properties have been extensively explored. This feature article collates the various MONs and their potential applications in the chemical and biological sensors for clinical and non-clinical applications.