Thec ontinued reduction of fossil fuels together with the more stringent environmental protection legislation has been the focal point for the search for alternative energy sources. Fuel cell technology has obtained increasing attention as it can directly convert chemical energy from fuel into electrical energy,w ithout combustion, at high efficiencya nd low pollution [1,2].R ecently,d irect alcohol fuel cells (DAFCs)h ave attracted enormous attentionf or their high energy density,e fficiency, simple operation at room temperature and simple storage of liquid fuels and fuel purification [ 3,4].DAFCs efficiencies are vary according to specific characteristics,b eing the choice of the fuel, anode catalyst and, corresponding catalyst support of utmost importance [5,6].T hese characteristics makea lcohols attractive liquid fuels for the majorityo fp romising alternative power sources for transportation, portable electronics and stationary applications [7].T he most common DAFC is the direct methanolf uel cell (DMFC) and severalw orks in the recent years have been performed on the electron oxidation of methanol [8] and ethanol [9][10][11].Recently,g lycerol has emerged as ap otential fuel to feed anodes of DAFCs,d irect glycerolf uel cell (DGFC), due to its high theoretical energya nd availability,s ince it is am assive co-product of biodiesel fabrication [12].I mproved alcohol oxidation kinetics in the electrolyte can also be facilitated in the alkalinem edia rather than in the acid media. This can help to overcomet he kineticc onstraintsi nt he alcohol oxidation for operating DAFCs [13,14].O ne of the most criticalp oints of DAFCs performance are the electrocatalysts,d ue to this,m uch effort has been devoted to the development of new materials in order to overcome this problem.Pt-basede lectrocatalysts are the most universal type applied in DAFCs because they have high catalytica ctivity,g ood chemical stability and large currentd ensity.A lthough, theya lso have certain limitations such as high cost, easy poisoning by the adsorbed reaction intermediates [3],a mong other factors.A nother approachf or improving the Pt efficiency has been the search of different support materials that may be appliedf or electrocatalysts synthesis.C arbon nanomaterials with several shapesa nd structures such as nanostructured, carbon black, carbon nanofibers,m esoporousc arbon and carbon nanotubes, have been used as support for metal nanoparticles improving their electrocatalytic performance [15].OrdóÇez et al. [16] prepared aP te lectrocatalyst supported ontom ulti-walled carbon nanotubes (MWCNTs) for direct ethanol fuel cell (DEFC)a pplication. Thea uthors described that CNTsi ncreased the activity of the Pt electrocatalyst and, in as ingle fuel cell tests occurred Abstract:Aphysical mixture composed by carbon Vulcan XC 72 and indiumt in oxide( ITO) with different ratios (85 :15; 50 :50; 85 :15) was used as support for platinum nanoparticles synthesis by borohydride reduction method. Thecharacterization of thiselectrocatalyst was pe...

Palladium electrocatalysts, supported on Vulcan XC 72 carbon and indium tin oxide (ITO) with different ratios, were prepared by borohydride reduction method and analysed for glycerol electro‐oxidation application in the presence of KOH solution. Transmission electron microscopy (TEM) and X‐ray diffraction (XRD) techniques were used to characterize the particle size and crystal electrocatalyst structures, whereas their catalytic activities regarding the glycerol electro‐oxidation were evaluated by cyclic voltammetry (CV), chronoamperometry and tested in a direct alkaline glycerol fuel cell (DGFC) by electrochemical techniques. Micrographs results showed that the ITO presence promotes a large agglomeration of particles. Pd/C–ITO electrocatalysts showed peaks associated with the face‐centered cubic (fcc) structure of palladium and several others peaks associated with ITO used as support. Similar performance was found on all Pd/C–ITO electrocatalysts where measurements in CV were compared to Pd/C and Pd/ITO with Pd/C–ITO 50:50 chronoamperometry, presenting a better performance for glycerol electro‐oxidation. When using Pd/C–ITO 85:15 electrocatalyst and 1.0 mol L−1 glycerol at 90 °C, the maximum power density found was 2,1 times higher than that obtained using Pd/C and Pd/CITO electrocatalysts. Therefore, the physical mixture of ITO and carbon, to be used as a support improves the electrocatalytic activity for glycerol oxidation reaction.

in different atomic proportions, with 20 wt.% of metal loading and supported on Vulcan XC72 carbon with high surface area. The materials were characterized by X-ray dispersive energy spectroscopy (EDX), X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM). The ethanol electrochemical oxidation was studied by cyclic voltammetry (CV), chronoamperometry and in situ using Fourier Transform Infrared Spectroscopy (FTIR) using the thin porous coating technique, Afterwards the materials were tested on direct ethanol alkaline fuel cells. The results suggest alloys formation, with the mean nanoparticles sizes are from 4-10 nm. According to the electrochemical experiments the ternary electrocatalysts presented higher electrocatalytic activity, while that the FTIR studies indicated that the main product of the electrochemical oxidation of ethanol in alkaline medium for all synthesized electrocatalysts was acetate, also suggesting that the oxidation occurs incompletely by the indirect mechanism. The fuel cell experiments showed the best results for PdAuIr/C (50:40:10), where these materials had an open circuit potential of approximately 0,78 V and maximum power density of about 15 mW cm-2 , about 333% higher than Pd/C.