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This study reports a facile approach for constructing low-cost and remarkable electroactivity iron vanadate (Fe-V-O) semiconductor material to be used as a photoelectrochemical sensor for dopamine detection. The structure and morphology of the iron vanadate obtained by the Successive Ionic Adsorption and Reaction process were critically characterized, and the photoelectrochemical characterization showed a high photoelectroactivity of the photoanode in visible light irradiation. Under best conditions, dopamine was detected by chronoamperometry at +0.35 V vs. Ag/AgCl, achieving two linear response ranges (between 1.21 and 30.32 μmol L−1, and between 30.32 and 72.77 μmol L−1). The limits of detection and quantification were 0.34 and 1.12 μmol L−1, respectively. Besides, the accuracy of the proposed electrode was assessed by determining dopamine in artificial cerebrospinal fluid, obtaining recovery values ranging from 98.7 to 102.4%. The selectivity was also evaluated by dopamine detection against several interferent species, demonstrating good precision and promising application for the proposed method. Furthermore, DFT-based electronic structure calculations were also conducted to help the interpretation. The dominant dopamine species were determined according to the experimental conditions, and their interaction with the iron vanadate photoanode was proposed. The improved light-induced DOP detection was likewise evaluated regarding the charge transfer process. [ABSTRACT FROM AUTHOR]

Inorganic metal oxide nanoparticles and nanocomposites may serve as effective disinfectants, due to their relatively nontoxic profile, chemical stability and efficient antibacterial activity. Fe2V4O13, Fe2V4O13/ZnO and Ag-ZnO/Fe2V4O13 have been prepared by sol-gel, liquid phase precipitation method and photodeposition method. Antibacterial activity was tested using ten microbes of biomedical and agriculturally significance was achieved. Synthesized nanoparticles are potential green remediators of polluted water and perilous pathogens. [ABSTRACT FROM AUTHOR]

A new hetero-Fenton type GO/Fe2V4O13 was developed and characterized by FT-IR, XRD, HR-SEM, TEM, and UV-DRS analysis. XRD pattern reveals the presence of monoclinic phase of Fe2V4O13 in the catalyst. TEM images show the particle sizes in the range from 20 to 100 nm and the nice dispersion of nanosized Fe2V4O13 particles on the surface of the graphene oxide. The hetero-Fenton catalyst was used for the degradation of Methyl orange (MO) under UV and solar light. The mineralization rate was influenced by H2O2 concentration, pH, and catalyst loading. The reusability 21% GO/Fe2V4O13 was analyzed. GO/Fe2V4O13 was stable and reusable up to five cycles with 95% degradation. Solar experiments were carried out at different initial solution pH with Fe2V4O13 and 21% GO/Fe2V4O13. Both catalysts show maximum degradation efficiency at pH 6. Mechanism of heterophoto-Fenton process is also proposed. This study reveals that Fe2V4O13 and 21% GO/Fe2V4O13 catalysts are efficient under UV and solar light for the degradation MO and can be utilized for the treatment of dye wastewater. [ABSTRACT FROM AUTHOR]

Iron tetrapolyvanadate (Fe2V4O13) was prepared and characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) measurement and scanning electron microscopy (SEM). It was found that Fe2V4O13 could effectively catalyse H2O2 to generate active OH; therefore, Fe2V4O13 was employed as a new two-metal heterogeneous Fenton-like catalyst. The decomposition of H2O2 and the degradation of Acid Orange II catalysed by Fe2V4O13 could be well described with a simple pseudo-first-order rate equation between the reaction temperatures of 15 °C and 30 °C. It was inferred from the reaction activation energy data that the generation of the hydroxyl radical was a control step in a series of reactions for the oxidation of Acid Orange II in the presence of H2O2 and Fe2V4O13. The catalytic activity of Fe2V4O13 towards degradation of Acid Orange II was not only much higher than that of α-Fe2O3, V2O5 and FeVO4 but also than that of their mixtures with an identical ratio of Fe and V, such as 2FeVO4 + V2O5 and Fe2O3 + 2V2O5. The high catalytic activity possibly involved a special two-way Fenton-like mechanism and the synergistic activation of Fe(III) and V(V) in Fe2V4O13 towards H2O2. [ABSTRACT FROM AUTHOR]

A new photo-Fenton-like catalyst with high activity, Fe2V4O13, has been found. It can be obtained by a simple wet chemical process. The catalyst has a nano-lamellar structure with a thinness of less than 100 nm, a BET surface of 52.26 m2 g−1, and a band-gap of 1.59 eV favorable to absorption of visible light. Experiments demonstrated that Fe2V4O13 could effectively catalyze degradation of Acid Orange II (AOII) by H2O2 in visible light. The degradation was well fitted by a simple pseudo-first-order reaction with a rate constant of 0.0965 min−1. Moreover, the photo-Fenton-like catalytic activity of Fe2V4O13 was much higher than that of not only α-Fe2O3 and V2O5 but also their mixture (Fe2O3 + 2V2O5) with an identical atomic ratio of Fe and V, and that of both Fe3O4 and γ-FeOOH. The high catalytic activity of Fe2V4O13 possibly involves a special two-way Fenton-like, semiconductor photo-catalytic mechanism and the synergistic activation of Fe(III) and V(V) in Fe2V4O13 towards H2O2. [ABSTRACT FROM AUTHOR]

Abstract: Amorphous Fe2V4O13 has been synthesized by the liquid precipitation method. The compound showed nano-lamellar structure with the average thickness of layer was about 40nm, which leads to an enhanced lithium ion transport and sustained volume variations. The initial specific capacity is 235mAh/g, and the specific capacity still remained 201mAh g−1 after 40 cycles at the rate of 0.25C in the range of 2.0–4.0V, which only brought about an 14% reduction of the capacity. The results show that the amorphous nanostructured Fe2V4O13 is a novel promising cathode material due to its high specific capacity, power density and good cycle performance. [Copyright &y& Elsevier]