| Fuel cells produce electricity from the energy of a fuel through a highly efficientdirect electrochemical conversion process, is extensively investigated as analternative for solving energy crisis, due to its low emissions and low environmentalimpact. Nowaday, most of the catalyst used in fuel cell is Pt-based catalyst. Theprohibitive cost of platinum for catalyzing the cathodic oxygen reduction reaction(ORR) has hampered the widespread use of fuel cells. This has stimulatedresearchers around the world to look for alternative materials that are cheaper and yetperform better or equivalent to the Pt standard.In this paper, we produced a novel incorporating TiO2/PANI compostite via atwo-step route. Then the as-prepared composite was pyrolyzed in N2. By varying theratio of PANI to TiO2and heating at various temperature between400°C to800°C,a serious of TiO2/C catalyst were achieved. At last, we synthetized Co/TiO2/C andFe/TiO2/C use Co(NO3)2·6H2O and FeCl3·6H2O as metal precursor. Besides, solventevaporation method and pyrolyzation were used to synthetize Co3O4/TiO2/C. Thesamples were characterized by XRD, Raman, SEM, TEM, FTIR, TGA and XPS.Additionally, LSV were used to explore the electrocatalytic activity of the samples.We also test the durability of the prepared catalysts in methanol.There is interaction between PANI nanofiber and TiO2, which inhibitaggregation of titanate nanoparticles and transformation from anatase to rutile. AndPANI transferred to graphitic carbon phase and titanate became rutile during theheating treatment，thus enhanced the electrochemical activity of samples. When theratio of PANI to TiO2is40to100and treated at800°C for1h, TiO2/C got thehighest catalytic activity.Adding Cobalt and Iron into TiO2/C enhance its activity, and the optimized ratioboth for Cobalt and Iron is5%. Compare with Pt based catalyst, Co/TiO2/C andFe/TiO2/C has durability in methanol, which is important in low temperature fuelcells such as direct methanol fuel cell (DMFC). |
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