M. K. Thakur; H. K. Singh;V. N. Singh; Om Pal Singh; Karuna Thakur; Rahul Parmar; Kuldeep Singh Gour; N. Muhunthan; Sandeep Singh; Dinesh Singh; N. Vijayan
Abstract
To be used as back contact for CZTS/CIGS thin film solar cell, good adhesion to the substrate and low resistivity of the Mo thin film is necessary. In this study, molybdenum thin film has been deposited on soda lime glass, sapphire, quartz, and a single crystal yttria-stabilized zirconia (YSZ) using ...
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To be used as back contact for CZTS/CIGS thin film solar cell, good adhesion to the substrate and low resistivity of the Mo thin film is necessary. In this study, molybdenum thin film has been deposited on soda lime glass, sapphire, quartz, and a single crystal yttria-stabilized zirconia (YSZ) using DC magnetron sputtering at 400°C. The structural, electrical, surface morphology and adhesion test using scotch tape test were carried out. Films deposited on all the substrates passed the adhesion test. Lattice parameter of films deposited on various substrates was almost same, but the strain % was different. The size of grain in the film deposited on soda lime glass and YSZ single crystals were larger compared to films deposited on quartz and sapphire. In the case of SLG, Na helped in the grain growth and in the case of YSZ, the crystalline nature of YSZ helped in grain growth. Resistivity result indicated films having pure metallic behavior. The resistivity for sample deposited on YSZ single crystal was very low. AFM study showed that the film made on soda lime glass is having higher surface roughness than other substrates and it was lowest for samples deposited on YSZ single crystal. The cross-sectional TEM study of Mo thin film deposited on glass showed columnar structure of the film.
Jagriti Narang; Utkarsh Jain; Nitesh Malhotra; Sandeep Singh; Nidhi Chauhan
Abstract
An amperometric lysine biosensor was fabricated by immobilizing lysine oxidase onto core shell magnetic nanoparticles (Core–shell MNPs)/multiwalled carbon nanotube (MWCNT) layer deposited on Au electrode via carbodiimide linkage. Transmission electron microscopy (TEM) for core–shell MNPs, ...
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An amperometric lysine biosensor was fabricated by immobilizing lysine oxidase onto core shell magnetic nanoparticles (Core–shell MNPs)/multiwalled carbon nanotube (MWCNT) layer deposited on Au electrode via carbodiimide linkage. Transmission electron microscopy (TEM) for core–shell MNPs, scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and Fourier transform impedance spectroscopy (FTIR) studies were used to characterize the modified electrode. Sensor showed optimal response within 2s at 30ºC in 0.05 M sodium phosphate buffer pH 6.0 when polarized at +0.2 V vs. Ag/AgCl. Linear working range of the biosensor was determined by 0.05 -700 μM with a detection limit of 0.05 μM. A good correlation (r = 0.98) was obtained between serum lysine levels measured by the standard HPLC method (y) and the present method (x). A number of serum substances had practically no interference. The sensor was used in 150 assays and had a storage life of 180 days at 4 o C. This nanohybrid biosensor will be useful for detection of lysine in food and pharmaceutical industries.
Jagriti Narang; Nitesh Malhotra; Nidhi Chauhan; Sandeep Singh; Gajendra Singh; C.S. Pundir
Abstract
A polyphenol oxidase (PPO) was immobilized by employing magnetic nanoparticles-zinc oxide/zinc hexacyanoferrate (Fe3O4NP-ZnO/ZnHCF) hybrid film electrodeposited on the surface of Pt electrode. The surface functionalization of Fe3O4NP-ZnO/ZnHCF hybrid film was characterized by cyclic voltammetry (CV), ...
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A polyphenol oxidase (PPO) was immobilized by employing magnetic nanoparticles-zinc oxide/zinc hexacyanoferrate (Fe3O4NP-ZnO/ZnHCF) hybrid film electrodeposited on the surface of Pt electrode. The surface functionalization of Fe3O4NP-ZnO/ZnHCF hybrid film was characterized by cyclic voltammetry (CV), scanning electron microscopy (SEM), atomic force microscopy (AFM) and electrochemical impedance spectroscopy (EIS) before and after immobilization of PPO. The biosensor exhibited optimum response within 4s at pH 7.0 and 35°C and linearity in the range 0.04 to 10000 μM for acetaminophen with a detection limit of 0.04 μM (S/N=3). Accuracy of the proposed sensor was found to be 99%. The use of Fe3O4NP/ZnO/ZnOHCF for construction of amperometric acetaminophen biosensor has resulted into relatively rapid response, higher sensitivity, broad linear range, lower detection limit, good reproducibility and long term stability of this biosensor. This sensing interface provides better avenue for the fabrication of various sensor.