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1.
Cobalt oxide (Co3O4) modified anatase titanium dioxide nanotubes (ATNTs) have been investigated for the electrochemical sensing of hydrogen peroxide (H2O2). ATNTs have been synthesized by a two-step anodization process. ATNTs were then modified with Co3O4 employing chemical bath deposition method. The structure and morphology of ATNTs and their modification with Co3O4 has been confirmed by X-ray diffraction by scanning electron microscopy. H2O2 sensing has been studied in 0.1 M PBS solution, by cyclic voltammetry and amperometry. Variation in the peak positions and current densities was observed with addition of H2O2 for Co3O4 modified ATNTs. Sensitivity and limit of detection improved with modification of ATNTs with Co3O4 with precursor concentration up to 0.8 M. However, at higher precursor concentrations sensitivity and limit of detection toward H2O2 deteriorated. Co3O4 Modified ATNTS using 0.8 M precursor concentration are comparatively more suitable for H2O2 sensing applications due to the optimum formation of Co3O4/ATNTs heterojunctions. 相似文献
2.
Shofu Matsuda Yuuki Okuda Yoshiki Obu Norio Nagayama Minoru Umeda 《Electroanalysis》2019,31(12):2466-2471
With the objective of understanding the kinetic redox properties of triphenylamine derivatives in association with chemical reactions, for their future application in functional organic semiconductor devices, the electrochemical characteristics of 4‐(2,2‐diphenylethenyl)‐N,N‐bis(4‐methylphenyl)‐benzenamine (TPA) were evaluated. Based on cyclic voltammograms of TPA on Pt disk electrodes with diameters of 300 μm and 10 μm at slow and fast scan rates in an acetonitrile solution, the TPA.+ is stable, while the TPA2+ is unstable. Importantly, the unstable TPA2+ appears to break down by a subsequent chemical reaction. A Cottrell plot analysis from chronoamperometry of a solution containing TPA reveals that both the first and second oxidations are one‐electron reactions. Concerning the stabilization mechanism of the first oxidation state of TPA, the results of molecular orbital calculations indicate that the electrons of the HOMO level are distributed in the triphenylamine group, which induces a resonance‐stabilized TPA.+. Based on these results, TPA/TPA.+ is suggested to have a sufficient stability for further application in organic semiconductor devices. 相似文献
3.
Tamil Selvi Gopal Soon Kwan Jeong Tahani A. Alrebdi Saravanan Pandiaraj Abdullah Alodhayb Muthumareeswaran Muthuramamoorthy 《Materials Today Chemistry》2022
A recently discovered 2D transition titanium metal carbides also called as MXenes (Ti3C2Tx)-based nanocomposite was prepared with Cu2O through wet precipitation technique, and these materials were further developed as the electrode for sensing glucose by chronoamperometry technique. The prepared MXene-Cu2O (Ti3C2Tx-Cu2O) nanocomposite was characterized by XRD, FTIR, UV–Vis spectroscopy, FE-SEM, EDAX, and Raman spectroscopy. Morphological studies of the composites revealed that the micro-octahedral shape of Cu2O is distributed on the surface of MXene with size larger than bare Cu2O. Further, the prepared composite material was fabricated as a sensing probe, and the electrochemical activities were examined by cyclic voltammetric analysis (CV) and chronoamperometric (CA) methods. From the CV and CA investigation, the current response was higher for the composite than the bare material (Cu2O & MXene) in the presence of glucose. The amperometric investigation of MXene-Cu2O composite for the detection of glucose shows a broad linear range (0.01–30 mM) with a sensitivity of 11.061/μAmM cm?2 and a detection limit of 2.83 μM. Further, the fabricated sensor exhibits good selectivity with interfering species like NaCl, fructose, sucrose, urea, ascorbic acid, lactose, short response time, stability, good reproducibility, and compatibility with human serum sample. From the investigation, the prepared MXene-Cu2O composite is a good candidate for the direct detection of glucose molecules and is also well suitable for clinical diagnosis. 相似文献
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6.
Jia-Kuo Liu Wei Gu Xiao-Rui Cheng Jun-Ping Cheng Wen-Xia Zhou Ai-Hua Nie 《中国化学快报》2015,26(10):1327-1330
Based on the lead compound 1 reported in literature, a series of novel BACE1 inhibitors were designed and synthesized, among which compound 11 exhibited a 14-fold improvement in potency over the lead compound 1. This represents a good lead for the discovery of more promising BACE1 inhibitors for the potential treatment of AD. 相似文献
7.
We describe the ultrasonic assisted preparation of barium stannate-graphitic carbon nitride nanocomposite (BSO-gCN) by a simple method and its application in electrochemical detection of 4-nitrophenol via electro-oxidation. A bath type ultrasonic cleaner with ultrasonic power and ultrasonic frequency of 100 W and 50 Hz, respectively, was used for the synthesis of BSO-gCN nanocomposite material. The prepared BSO-gCN nanocomposite was characterized by employing several spectroscopic and microscopic techniques such as X-ray diffraction, X-ray photoelectron spectroscopy, fourier transform infra-red, field emission scanning electron microscopy, and high resolution transmission electron microscopy, to unravel the structural and electronic features of the prepared nanocomposite. The BSO-gCN was drop-casted on a pre-treated glassy carbon electrode (GCE), and their sensor electrode was utilized for electrochemical sensing of 4-nitrophenol (4-NP). The BSO-gCN modified GCE exhibited better electrochemical sensing behavior than the bare GCE and other investigated electrodes. The electroanalytical parameters such as charge transfer coefficient (α = 0.5), the rate constant for electron transfer (ks = 1.16 s−1) and number of electron transferred were calculated. Linear sweep voltammetry (LSV) exhibited increase in peak current linearly with 4-NP concentration in the range between 1.6 and 50 μM. The lowest detection limit (LoD) was calculated to be 1 μM and sensitivity of 0.81 μA μM−1 cm−2. A 100-fold excess of various ions, such as Ca2+, Na+, K+, Cl−, I−, CO32−, NO3, NH4+ and SO42− did not able to interfere with the determination of 4-NP and high sensitivity for detecting 4-NP in real samples was achieved. This newly developed BSO-gCN could be a potential candidate for electrochemical sensor applications. 相似文献
8.
《Journal of Pure and Applied Algebra》2019,223(11):5030-5048
Take positive integers m, n and d. Let Y be an m-fold cyclic cover of ramified over a general hypersurface of degree md. In this paper we study the space of lines in Y and show that it is smooth of dimension if and . When , our result gives a formula on the number of m-contact order lines of X (see Definition 1.2). 相似文献
9.
Redox graphene-MXene(rGO-MXene) nanocomposites were prepared by ion polymerization and used to construct a highly sensitive electrochemical sensor for baicalin(BA) detection. The synergistic effect of rGO and MXene increased the specific surface area and electron transport capacity of the electrode, and significantly enhanced the electrochemical response of BA. The cyclic voltammetry and differential pulse voltammetry were used to investigate the electrochemical behavior of BA on the sensor. Under the optimal conditions, the peak current exhibited a good linear relationship with BA concentration in the range of 0. 05-10 μmol / L, and the limit of detection was as low as 28 nmol / L. The method was applied to analyze traditional Chinese medicine preparations containing baicalin, such as Qingkailing Capsule and Sanhuang Tablets with good accuracy and spiked recovery. The results were highly consistent with those of high performance liquid chromatography, providing a technical means for the rapid and sensitive detection of traditional Chinese medicine preparations. © 2022, Youke Publishing Co.,Ltd. All rights reserved. 相似文献
10.
Keerakit Kaewket Pattanaphong Janphuang Peerawat Laohana Nantawat Tanapongpisit Wittawat Saenrang Kamonwad Ngamchuea 《Electroanalysis》2023,35(2):e202200200
Silver microelectrode arrays are fabricated by photolithography for a one-step analysis of H2O2 in low ionic strength samples. The effects of electrode length, width, band-to-band separation, connection height, and adhesion layer are evaluated. The developed sensor shows excellent repeatability (RSD=1.20 % (n=5)) and reproducibility (RSD=1.12 % (n=5)) with the linear range of 0.0–10.0 mM, the sensitivity of 9.84±0.34 μA mM−1, and the detection limit of 22.69 μM. The sensor has been successfully applied to detect H2O2 directly without the addition of supporting electrolyte in synthetic urine, tap water, drinking water, and milk samples. 相似文献