Faculty Publications

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Subject: search.filters.subject.Doped zinc oxides

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    Electro-oxidation of nimesulide at 5% barium-doped zinc oxide nanoparticle modified glassy carbon electrode
    (Elsevier B.V., 2016) Bukkitgar, S.D.; Shetti, N.P.; Kulkarni, R.M.; Doddamani, M.R.
    Development of methods for the detection of an analyte at low concentration with less time for analysis has become a prior point of interest to every analyst. In reflection of this fact, an effort has been made to synthesize 5% barium doped zinc oxide nanoparticles and was characterized by using XRD, EDX, SEM, and TEM. Further, 5% barium doped zinc oxide nanoparticle modified glassy carbon electrode was used for investigating the electro-chemical behavior of nimesulide. Voltammograms obtained in a range of 3.0-11.2 (I = 0.2 M) pH had a maximum peak current at pH 7.0. Various physio-chemical parameters such as, process on the surface of the electrode, which was found to be diffusion controlled, heterogeneous rate constant, number of electrons transferred and charge transfer coefficient were estimated. Further, a method for nimesulide determination in a linear range of 1.0 × 10- 5 to 1.0 × 10- 7 M with LOD 1.794 nM was proposed. This technique was later used for analytical application. © 2015 Elsevier Ltd. All rights reserved.
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    Cerium-Modulated Zinc Oxide for enhanced Photoelectrochemical Non-Enzymatic biosensing of Cholesterol: An experimental and First Principle Analysis
    (Elsevier B.V., 2024) Rao, L.; Rodney, J.D.; Joy, A.; Shivangi Nileshbhai, C.; James, A.; S, S.; Joyline Mascarenhas, F.; Udayashankar, N.K.; Anjukandi, P.; Chul Kim, B.; Badekai Ramachandra, B.R.
    Herein, we synthesized CexZn1-xO (x = 0.00, 0.01, 0.02, and 0.03) using the wet chemical method. The investigation explores photoelectrochemical (PEC) biosensors for enzyme-free detection of cholesterol, employing Ce0.03Zn0.97O (CZO3)/Nickel Foam (NF) as the active material. The investigation revealed notable enhancements in sensitivity for cholesterol detection, with a recorded activity of 2.812 mA.mM?1.cm?2, marking a twofold increase in comparison to dark mode (1.37 mA.mM?1.cm?2). The Limit of Detection (LOD) was determined to be 17 µM (light) and 28 µM (dark), while the Limit of Quantification (LOQ) was measured at 54 µM (light) and 98 µM (dark) in 0.1 M KOH solution. These findings demonstrate a linear detection range spanning from 80 µM to 2 mM. Ab-initio calculations based on Density Functional Theory (DFT) were carried out on 101 surfaces of both pristine ZnO and CZO3 to understand how the doping affected the pristine ZnO band gap. The findings indicate that CZO3 exhibits superior activity compared to pristine ZnO, underscoring its enhanced performance and potential for sensing application. The CZO3/NF photoelectrochemical (PEC) biosensor displayed notable cyclic stability, retaining 97 % of its performance over a 60-day period. This underscores its potential for reliable and enduring operation in biosensing applications. Additionally, CZO3/NF exhibited robust sensing capabilities when utilized with human serum samples, showcasing consistent performance in both dark and illuminated conditions. © 2024 Elsevier B.V.
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    Effect of Ni doping on the acetone vapor sensing performance of ZnO nanofibers
    (Elsevier Ltd, 2025) Prabhu, N.N.; Shivamurty, B.; Anandhan, S.; Rajendra, B.V.; Kulkarni, S.D.
    Nickel-doped zinc oxide (NiZ) nanofibres (NFs) were fabricated using sol-gel electrospinning (ES) technique followed by pyrolysis from an aqueous solution of polyvinyl alcohol/zinc acetate/nickel acetate tetrahydrate. The morphology of the NiZ NFs was analyzed using Scanning Electron Microscopy (SEM), which revealed a uniform and well-defined fibrous structure. X-ray diffraction (XRD) results indicated complete removal of the organic phase from NiZ NFs during pyrolysis. The structural analysis confirmed the incorporation of Nickel (Ni) into the Zinc oxide (ZnO) lattice without altering its wurtzite crystal structure. The optical properties and bandgap variations were evaluated using UV–visible spectroscopy, which indicated a bandgap narrowing with increasing Nickel doping. The Photoluminescence (PL) spectroscopy confirmed the presence of defect states and recombination processes in the NFs. The gas sensing performance was investigated by measuring the response to various analytes at a concentration of 50 ppm with varying operating temperatures. The results indicated that the highest response was observed for 5 w% NiZ NFs towards acetone vapors. The response and recovery time were recorded at 80 s and 60 s. The enhanced sensitivity is attributed to the optimal doping concentration, which significantly improves the surface reaction and charge carrier mobility. © 2024 The Authors