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91.
采用溶液相牺牲模板法制备中空多孔金纳米粒子(HPAuNPs),并将该材料与还原氧化石墨烯(rGO)复合,用于葡萄糖氧化酶(GOx)在玻碳电极(GCE)表面的有效固定,构建GOx/HPAuNPs/rGO/GCE传感界面。利用扫描和透射电镜、X射线光电子能谱、X射线衍射谱、红外光谱及电化学等方法对材料的形貌与结构,GOx的固定化过程,以及传感器的直接电化学和电催化性能进行表征。结果表明,HPAuNPs和rGO的协同作用能有效促进GOx与电极之间的直接电子转移(DET)。基于GOx/HPAuNPs/rGO/GCE对葡萄糖的良好电催化性能,该方法有效实现了对葡萄糖的高灵敏度检测,其电流响应的线性范围为0.05~7.0 mmol/L,检出限(S/N=3)为16μmol/L。该传感器具有良好的选择性、重现性及稳定性,对实际样品血清中血糖的测定结果令人满意,回收率为98.0%~103%,相对标准偏差不大于5.0%。 相似文献
92.
Surin Saipanya Li Fang Suwaphid Themsirimongkon Suphitsara Maturost Natthapong Pongpichayakul Napapha Promsawan Paralee Waenkaew 《先进技术聚合物》2023,34(1):120-133
The aim of this research was to study the efficiency of polyvinyl alcohol (PVA)-modified graphene oxide (GO) as a supporting material for catalysts that oxidize formic acid. The active metal catalysts (e.g., Pt and Pd) were electrodeposited on PVA/GO surfaces. The morphologies of the prepared catalysts were characterized by scanning electron microscopy and transmission electron microscopy, while their chemical compositions were identified by X-ray diffraction and X-ray photoelectron spectroscopy. The results show that compared with the other catalysts on GO, the prepared active PtPd alloy catalyst nanoparticles with 11.49–20.73 nm sizes were well dispersed on the PVA/GO surfaces. Electrochemical results indicate that the activities of the catalysts with PVA provided a higher current density than that of the catalysts without PVA. The bimetallic 3Pt3Pd/PVA/GO catalyst showed the greatest catalytic activity, stability, and CO oxidation when compared to those of other catalysts. The electronic, morphological, and structural properties promote the mass-charge transfer through the interaction. These results indicate that the PVA-modified GO provides a suitable site for active bimetallic catalyst surfaces, resulting in excellent formic acid oxidation and high CO elimination. The 3Pt3Pd/PVA/GO electrocatalyst is promising for enhancing formic acid oxidation. 相似文献
93.
In this study, tetracarboxylic manganese phthalocyanine coated nano-zinc oxide (MnC4Pc-ZnO) composite material was prepared by in-situ growth method and modified with indium tin oxide (ITO) glass electrode to construct a photoelectrochemical (PEC) sensor. A PEC sensor for the determination of amlodipine besylate (AB) was developed for the first time based on the principle of precipitation reaction between heavy metal ions and dihydropyridine and the recombination suppression effect of the material. The morphology and optical properties of the MnC4Pc-ZnO composites were characterized by scanning electron microscopy (SEM) and ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS). Chronoamperometry (i-t) and electrochemical impedance spectroscopy (EIS) were used to study the PEC behavior of ITO electrodes modified by MnC4Pc-ZnO composite material. The study found that the MnC4Pc-ZnO composite material has a good photocurrent response to AB, and there was a good linear relationship between the concentration range of 75 nM-250 μM, the linear equation was I(μA)=−5.2×10−8×lgC+3.2×10−8 (r=0.9947), a limit of detection (LOD) of 20 nM. In addition, MnC4Pc-ZnO/ITO also has good selectivity and stability. The PEC sensor detects amlodipine besylate tablets, amlodipine besylate dispersible tablets, and biological samples, with standard addition recovery rates of 96.11 % and 103.96 %, respectively. The determination result has good accuracy, and the PEC sensor provides a new method for detecting AB. 相似文献
94.
Darko Kwabena Adu Zondi Nate John Alake Blessing Wisdom Ike Ruchika Chauhan Prof. Rajshekhar Karpoormath 《Electroanalysis》2023,35(3):e202200216
Solvothermally synthesized cobalt sulphide/reduced graphene oxide (CoS/rGO) was used to fabricate an electrochemical sensor for detection of artemisinin. Microscopic techniques were used to characterize CoS/rGO nanocomposite. The electrochemical sensor was fabricated by modifying the surface of glassy carbon electrode with CoS/rGO nanocomposite. [Fe(CN)6]3−/4− was used as a mediator to aid oxidation of artemisinin. Differential pulse voltammetric technique was used for the detection of artemisinin. A linear range of 30–100 μM was used. Experimentally, a detection limit of 0.5 μM was obtained. Therefore, the developed sensor can be used for quality control of artemisinin. 相似文献
95.
The electroactive composites based on reduced graphene oxide (RGO), poly-o-phenylenediamine (PPD) and heteropolyacids – H4SiW12O40nH2O (SiW) and H3[PW12O40] ⋅ nH2O (PW) was applied to a screen-printed carbon electrode (SPCE) as a planar three-electrode cell as the first step to creating various devices, in particular, sensors and catalysts. We studied potential use of the modified and unmodified SPCE planar electrode in determining the concentration of antitubercular antibiotic isoniazid (isonicotinic acid hydrazide C6H7N3O or INH). The best result was observed for SPCE+RGO-PPD-SiW. CV of normal saline with various concentrations of C6H7N3O demonstrated linear dependence of the relevant anodic peak current either in the bulk solution upon immersion of the modified electrode or in a droplet on the electrode surface. 相似文献
96.
Priscila I. Soares Thaís M. Lima Luiza. A. do Nascimento Rafael M. Coelho Diego L. Franco Arnaldo C. Pereira Lucas F. Ferreira 《Electroanalysis》2023,35(5):e202200302
Caffeic acid (CA)-modified graphite electrodes [GE/poly(CA)] was applied to the co-detection of copper and lead in artisanal sugarcane spirit using square-wave anodic stripping voltammetry (SWASV). Electrochemical and morphological studies were performed, and a mechanism for polymerization was proposed. Electropolymerization, SWASV, and analysis conditions parameters were optimized. Interferents, repeatability, reproducibility, and addition and recovery tests were carried out. GE/poly(CA) shows a linear range from 15 to 705 μg/L with a limit of detection of 3.01 μg/L for Pb(II) and 4.50 μg/L for Cu(II). Real samples of artisanal sugarcane spirit were used, and the electrochemical results were compared with atomic absorption spectroscopy experiments. 相似文献
97.
Alexandra Belcovici Carmen Ioana Fort Laura Elena Mureşan Ioana Perhaiţa Gheorge Borodi Graziella Liana Turdean 《Electroanalysis》2023,35(5):e202200395
ZnO nanoparticles (ZnO-NP) were prepared by a facile precipitation technique using di-isopropyl amine as precipitating agent. The morpho-structure and porosity of the as-prepared nano-powder were investigated by FT-IR analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), and BET analysis. By drop-casting, a composite film was deposited to obtain ZnO-NP-Nafion/GCE modified electrode. The modified electrode was investigated by cyclic voltammetry, electrochemical impedance spectroscopy, and square wave anodic stripping voltammetry (SWASV) for the detection of Pb2+, Cd2+, Cu2+, and Fe3+, and it was successfully applied for the detection of Pb2+ and Cu2+ in real water samples. 相似文献
98.
《印度化学会志》2023,100(2):100901
The novel calcium titanate-lithium lanthanum titanate doped with zinc oxide (0.10, 0.30, and 0.50 mol. %) ceramic samples were prepared by solid-state reaction route. The phase formation, microstructure, densification, and microwave dielectric properties were investigated. It was found that the doping with zinc oxide led to a decrease in sintering temperature by 25 oC as compared with pure calcium titanate lithium lanthanum titanate due to the liquid phase effect. Also, the calcium titanate lithium lanthanum titanate (10ZCTLLT&30ZCTLLT)) doped with lower zinc oxide (0.10 and 0.30 mol. %) led to higher densification parameter. This was followed by increasing the zinc oxide doping up to (0.50 mol. %) which resulted in a decrease in densification and microwave dielectric properties which may be attributed to increase in porosity and grain growth upon the evaporation of zinc and oxygen vacancy. This led to the increase in dielectric loss (≈10 × 10?4) value with 50ZCTLLT. Hence, the best result of microwave dielectric characteristics was obtained for 0.5CaTiO3–0.5(Li0.5La0.5)TiO3 with (0.10 and 0.30 mol. % ZnO) 10ZCTLLT and 30ZCTLLT ceramic samples sintered at 1175 oC/2h, with low dielectric constant (εr) = 4.4–10.5, very low dielectric loss = 1.07-2.23 × 10?4 and high quality factor (Q x ?) ≈59-55 × 104 at 8 GHz. Consequently, they can be used not only in wireless satellite communications technology but also can be used in the fifth-generation telecommunication 5G technology construction. 相似文献
99.
Dr. Aline Varella Rodrigues Bruno Seiki Domingos Onishi Prof. Dr. Sidney José Lima Ribeiro 《Chemphyschem》2023,24(21):e202300134
This research endeavors to overcome the significant challenge of developing materials that simultaneously possess photostability and photosensitivity to UV-visible irradiation. Sulfurized nanorod (NR)-like ZnO/Zn(OH)2 and hierarchical flower-like γ-Zn(OH)2/ϵ-Zn(OH)2 were identified from XRD diffraction patterns and Raman vibrational modes. The sulfurized material, observed by FEG-SEM and TEM, showed diameters ranging from 10 and 40 nm and lengths exceeding 200 nm. The S2− ions intercalated Zn2+, modulating NRs to dumbbell-like microrods. SAED and HRTEM illustrated the atomic structure in (101) crystal plane. Its direct band gap of 3.0 eV was attributed to the oxygen vacancies, which also contribute to the deep-level emissions at 422 and 485 nm. BET indicated specific surface area of 4.4 m2 g−1 and pore size as mesoporosity, which are higher compared to the non-sulfurized analogue. These findings were consistent with the observed photocurrent, photostability and photoluminescence (PL), further supporting the suitability of sulfurized NR-like ZnO/Zn(OH)2 as a promising candidate for Luminescent solar concentrators (LSC)-photovoltaic (PV) system. 相似文献
100.
Bize Gao Dr. Quanren Zhu Prof. Dr. Yanhui Yi Yue Li Guoxing Wu Yitong Guo Prof. Dr. Zhaochi Feng Prof. Dr. Hongchen Guo 《欧洲无机化学杂志》2023,26(22):e202200661
The epoxidation of propylene with dilute H2O2 aqueous solution over titanium silicalite-1 (TS-1) zeolite catalyst is a green chemical reaction for propylene oxide (PO) production. Carrying out the reaction in gas-phase can get rid of problems caused by using methanol solvent. This paper reports an attempt of using non-zeolite catalyst for the gas-phase epoxidation. Amorphous Ti/SiO2, obtained by grafting amorphous SiO2 with TCl4 in ethanol solvent in a chemical liquid-phase deposition (CLD) process, has been used as the catalyst. Results show that the CLD Ti/SiO2 with appropriate Si/Ti molar ratio is an active catalyst for gas-phase epoxidation, achieving 9.8 % propylene conversion and 66.9 % PO selectivity with 40.3 % H2O2 utilization, which indicates that this amorphous Ti/SiO2 catalyst deserves extensive studies in the future. 相似文献