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In this article, an optical bio-chemical sensor based on D-shaped optical fiber is presented for ethanol detection application. The gold and graphene nanolayers are coated for inducing the SPR over an optical fiber flat surface. The molecularly imprinted polymer (MIP) thin film is also coated over the gold film to enhance the molecular interaction between the sensing fluid and the sensing surface. The ethanol concentration is detected with reference to the 0% concentration and increased to 90% in a sample solution. The shift in resonance wavelength detects the concentration of the ethanol in the fluid sample due to the change in RI. The result shows a very good agreement between the concentration of ethanol in fluid and the resonance wavelength (RW) shift. The maximum obtained average sensitivity is 2.5 nm/concentration (every 10%) or 714 nm/RIU with Au/MIP thin film and 1137 nm/RIU for graphene/Au/MIP thin film. Based on the result and optical properties of the proposed sensor, it might be used as a real-time alcohol detector. This sensor can protect foods and drinks from the imbalance of chemicals and preservatives. [ABSTRACT FROM AUTHOR]

The work reports on the interaction of the photo electrodes with the electrolytes and dyes since it is imperative to investigate the degradation behavior of the transparent conducting electrodes in terms of structural, optical and electrical properties along with the corrosion resistance behavior. Three electrodes, one indium tin oxide (ITO) and two aluminium doped zinc oxide (AZO), two dyes (Eosin Yellow and Ruthenium Red), and two electrolytes, potassium iodide (KI) and lithium iodide (LiI) were used in this investigation. Twelve solar cells were fabricated with the aforementioned combination of electrodes, dyes and electrolytes. Open circuit voltage (Voc) of the fabricated cells as a function of time (for 30 days) were recorded. Changes in the structure and elemental composition of the electrodes after interaction with the dye and electrolyte were analyzed using X-Ray Diffraction and EDX, respectively. Transparency and sheet resistance of the electrodes before and after interaction with electrolytes and dyes was observed. Corrosion behavior of the three electrodes was studied using an electrochemical analyzer with KI and LiI electrolytes. [ABSTRACT FROM AUTHOR]

Reports on the optical characterization of positive electrode (e.g. MEH-PPV/Alq3) composite made by studying its absorption and photoluminescence spectra. Growing of the MEH-PPV films over glass substrate using spin cast technique; Conclusion that optical properties of MEH-PPV films is greatly improved by using a bilayer heterostructure with Alq3.

Bias-induced oxygen ion dynamics underpins a broad spectrum of electroresistive and memristive phenomena in oxide materials. Although widely studied by device-level and local voltage-current spectroscopies, the relationship between electroresistive phenomena, local electrochemical behaviors, and microstructures remains elusive. Here, the interplay between history-dependent electronic transport and electrochemical phenomena in a NiO single crystalline thin film with a number of well-defined defect types is explored on the nanometer scale using an atomic force microscopy-based technique. A variety of electrochemically-active regions were observed and spatially resolved relationship between the electronic and electrochemical phenomena was revealed. The regions with pronounced electroresistive activity were further correlated with defects identified by scanning transmission electron microscopy. Using fully coupled mechanical-electrochemical modeling, we illustrate that the spatial distribution of strain plays an important role in electrochemical and electroresistive phenomena. These studies illustrate an approach for simultaneous mapping of the electronic and ionic transport on a single defective structure level such as dislocations or interfaces, and pave the way for creating libraries of defect-specific electrochemical responses. [ABSTRACT FROM AUTHOR]