In this research, we demonstrate a disposable carbon-based paper electrode with engineered surfaces that is capable of detecting glucose in an alkaline medium at concentrations down to 10 μM. The sensitive electrode is fabricated by introducing a hydrothermally synthesized nickel oxide (NiO) layer on a carbon paper electrode, followed by the growth of nanostructured molybdenum disulfide (MoS 2 ) by pulsed laser deposition on the NiO layer. The surface modification was investigated using transmission electron microscopy and micro-Raman spectroscopy. The electrocatalytic activity of the fabricated electrodes was investigated in presence of a low concentration (0.1 mM) of an alkaline solution of sodium hydroxide. The catalytic enhancement of a NiO−MoS 2 hybrid electrode is attributed to the edge sites and defects associated with MoS 2 nanostructures responsible for creating a highly reactive environment. This system dissociates a water molecule into OH − and H + species. H + continues to diffuse on the MoS 2 surface, simultaneously modifying it due to its quantum nature. On the addition of glucose molecules into the electrolyte, an oxidation reaction takes place at the surface of the electrode, realizing an enzyme-free glucose sensor. Simulations are carried out via a thin-film-based electrochemical sensor model to better understand the trends in the experimental results. These results indicate a new route to detect glucose at low concentrations and with high sensitivity.

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In this paper, we report the synthesis of dumbbell-shaped ZnO structures and their subsequent transformation into perfect hexagonal tubes by the extended chemical bath deposition (CBD) method, retaining all advantages such as reproducibility, simplicity, quickness and economical aspect. Well-dispersed sub-micron-sized dumbbell-shaped ZnO structures were synthesized on a SiO2/Si substrate by the CBD method. As an extension of the CBD process the synthesized ZnO dumbbells were exposed to the evaporate coming out of the chemical bath for a few minutes (simply by adjusting the height of the deposit so that it remained just above the solution) to convert them into hexagonal tubes via the dissolution process. The possible dissolution mechanism responsible for the observed conversion is discussed. The optical properties (photo-luminescence) recorded at low temperature on both the structures showed an intense, sharp excitonic peak located at ∼370 nm. The improved intensity and low FWHM of the UV peak observed in the hexagonal tubular structures assures high optical quality, and hence can be used for optoelectronic applications.

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