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@InProceedings{OishiCoutBoteFerr:2017:EfSiPa,
               author = "Oishi, Silvia Sizuka and Couto, Andrea Boldarini and Botelho, 
                         Edson Cocchieri and Ferreiraa, Neiden{\^e}i Gomes",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {} and 
                         {Universidade Estadual Paulista (UNESP)} and {Instituto Nacional 
                         de Pesquisas Espaciais (INPE)}",
                title = "Effect of silver particles electrodeposited on reticulated 
                         vitreous carbon for nitrate reduction",
                 year = "2017",
         organization = "ECS Meeting, 232.",
             abstract = "Nitrate is a serious contaminant of ground and surface water, 
                         which cause high concern in the field of health and environmental 
                         protection. Many processes have been used for nitrate removal and 
                         the electrochemical treatment is one of the most efficient due to 
                         its advantages regarding low cost effectiveness and ability to 
                         treat highly concentrated nitrate effluents. The cathode material 
                         is an important variable for the nitrate electroreduction process 
                         and the development of new electrodes to improve their catalytic 
                         activity is a challenge. Modification of electrodes by 
                         electrodeposition of metals has been frequently used for 
                         electrocatalysis of various reactions in solution and carbon 
                         materials are often used as supports for electrocatalysts. In this 
                         work, the reticulated vitreous carbon (RVC) was used as support 
                         for silver eletrodeposition and the effect of different parameters 
                         (applied potential, AgNO3 concentration and deposition time) on 
                         the morphology and electrocatalytic activity for nitrate reduction 
                         was studied. RVC was processed using poly(furfuryl alcohol) (PFA) 
                         resin synthesized according to the best condition established 
                         previously. Polyurethane foams with 70 ppi (pores per inch) were 
                         used as matrix for the PFA anchorage and after curing, they were 
                         heat treated at 1000 C. All electrochemical experiments were 
                         performed in a conventional three electrode cell, using the RVC 
                         with electrodeposited Ag as working electrode, a Pt screen and 
                         Ag/AgCl as the counter and reference electrodes, respectively. The 
                         deposition potentials were chosen through cyclic voltammetry at 
                         0.1, -0.3 and -0.7 V vs Ag/AgCl that can be related to the 
                         following regions, respectively: onset of Ag deposition, massive 
                         deposition and diffusion controlled deposition. The AgNO3 
                         concentrations solutions used were 5, 10 and 20 mmol L-1, and the 
                         deposition times applied were 10, 60 and 180 s. The morphologies 
                         obtained by field emission scanning electron microscopy (FESEM) 
                         showed that Ag deposition is not uniform due to the RVC 
                         three-dimensional structure. Ag dendrites were formed on the 
                         highest RVC stems as shown in Figure 1. Ag aggregates of different 
                         sizes and shapes dispersed on the entire electrode surface could 
                         be observed depending on the experimental condition employed and 
                         sample depth. Difference in electrocatalytic activity of the 
                         Ag/RVC electrodes for nitrate reduction was confirmed by cyclic 
                         voltammetry in 0.1 mol L-1 K2SO4 solution containing 0.01 mol L-1 
                         KNO3 and varied with the Ag amount on electrode surface in 
                         addition to its morphology.",
  conference-location = "National Harbor, MD",
      conference-year = "01-05 Oct.",
             language = "en",
        urlaccessdate = "29 nov. 2020"
}


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