TATIANE YUMI TATEI
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Resumo IPEN-doc 26978 Green synthesis of ZnO nanostructured electrode for supercapacitor2017 - GALEGO, EGUIBERTO; SERNA, MARILENE M.; TATEI, TATIANE Y.; LIMA, BRUNA R.; FARIA, RUBENS N.The electrical double layer capacitor (EDLC), has been extensively investigated for its many applications in electric and electronic devices, due to high power density and long-life cycle. Zinc oxide (ZnO) is a promising candidate for the electrochemical supercapacitor electrode. ZnO is well known to be an active battery electrode material with a high energy density of about 650 Ag-1 [1], but it has the disadvantage of dendrites formation during consecutive cycling, which decreases life cycle. In this paper, we report a relatively straightforward, environmental friendly and low-cost method for preparing ZnO electrodes that consists in two steps. Starting with a ZnO seed layer onto a steel substrate employing the successive ionic layer adsorption and reaction (SILAR) method [2]. Subsequently, a chemical deposition bath was used for the nanostructured ZnO growth. A low temperature SILAR method was used in this study, replacing high temperature and vacuum methods, such as chemical vapor deposition or sputtering, to create an interface region between the conductive steel current collector and the nanostructured ZnO electrode. Scanning electronic microscopy has been employed in the characterization of the two-step produced nanostructured ZnO electrodes. The electrochemical performance of the nanocomposite electrodes has been investigated using cyclic voltammetry (10 to 50) mVs-1 and charge-discharge curves (1 to 20) mAcm-2 in aqueous KOH electrolyte at several concentrations. Cyclic voltammetry exhibited a broad redox peak indicative of typical reversible redox reaction of ZnO with the K+, responsible for the faradaic reactions in the supercapacitor. The enhanced electrochemical performance has been attributed to the synergistic effects of pseudo-capacitance behavior of the ZnO phase grown on the ZnO seeds and to the nanostructured features of the electrode.Artigo IPEN-doc 26327 Prospects for nuclear energy in Brazil2019 - MOREIRA, RENAN P.; TATEI, TATIANE Y.; ARAUJO, DANIELLE G.; DUQUE, MARCO A. da S.; OLIVEIRA, IVAN C. de; AYOUB, JAMIL M.S.; SENEDA, JOSE A.One of the main purposes of nuclear technology is to produce electricity, with the advantage of producing a lower volume of radioactive waste. The expansion of nuclear energy in the electrical system has been positive, as it is one of the types of energy that is available at any time and in the desired amount. Considered a reliable source and safe alternative to compose a country's energy matrix. In the case of Brazil, it has enough reserves of Uranium and Thorium to compose the energy matrix over many years. The increase in demand, and the need for energy from renewable sources has caused changes in the world's electric power generation. According to World Nuclear Association (WNA), 14% of the energy is generated by nuclear energy sources, and this percentage tends to increase with the construction of new plants. According to the International Atomic Energy Agency (IAEA), the goal for nuclear energy is to provide 25% of electricity in 2050. Other technologies are applied in the nuclear area, for example nuclear medicine, in which radioactive materials are used with low doses of radiation for treatment and diagnosis of diseases, even in development are effective and safe, especially in the areas of cardiological, neurological and oncological diagnosis. Despite the knowledge acquired with the development of Brazilian nuclear projects, many are partly lost and discontinuity investments of successive governments, therefore, this work intends to study an overview of nuclear energy in Brazil in recent years and its prospects.