| Direct methanol fuel cells (DMFC) are the most suitable for mobile and portable electronic applications because of their high energy density, relatively low operating temperature, and the convenience of a liquid fuel that, thereby, enables a greatly simplified system design. Carbon supported platinum is commonly used as the anode electrocatalyst. However, one of the problems is sluggish methanol oxidation kinetics at the anode, which is made worse by the progressive loss of catalytically active sites by CO-like reaction intermediates that are generated during the stepwise dehydrogenation of methanol. Therefore, the efforts to icrease the efficiency of DMFC still focused on improvement in the performance of anode electrocatalyts.Pitch-based carbon submicron-particles (PCSP) was small carbonanous particles with the size <1.0μm, and separated from mesocarbon mcirobeads (MCMB), which was obtained during the formation and development process of carbonaceous mesophase. PCSP was considered as the basic units of the formation and development of MCMB. However, a large amount of PCSP, which was the byproduct produced during the industrial manufacture of MCMB, is of no use for application due to lacking of profound knowledge of its properties and of the basic research of its application. In order to utilize PCSP effectively, reduce the cost of DMFC and improve the anode electrocatalyst performance, in this paper, exploratory researches were done by using the graphitic PCSP (GPCSP) as the novel supports for Pt-based electrocataysts, and it is expected for GPCSP supported Pt-based electrocatalysts to obtain high performance of methanol electro-oxidation.First, GPCSP was treated by KOH activation, HNO3 oxidation, air oxidation, and thermal treatment in N2 flow, respectively. After KOH activation, HNO3 and air oxidation, the specific surface area of GPCSP increased, and oxygen-contained groups were formed on the surface of GPCSP. After thermal treatment, the specific surface area of GPCSP changed slightly, and the amount of oxygen-contained groups decreased obviously.The analysis of methanol oxidation showed that the mass specific activity of 10 wt% Pt/S0 electrocatalyst was 850 mA·mgPt-1, with a 30 % increase than that of 10wt% Pt/CB electrocatalyst. This increase in the activity of methanol oxidation for Pt/GPCSP electrocatalysts was attributed to the characteristics of the support, such as the high conductivity and graphitized degree. The performance of the Pt/GPCSP electrocatalysts was affected by using the different pre-treated supports. Among the all electrocatalysts, the Pt/SKN electrocatalysts showed the most highly catalytic activity for the oxidation of methanol. The activity of Pt/GPCSP electrocatalysts decreased slightly after the thermal treatment in N2 flow at 300℃; and after thermal treatment at 900℃, its activity decreased obviously.The atomic compostions for 10 wt(Pt+Ru)% Pt-Ru/GPCSP electrocatalysts were nearly 85:15. But there was a large excess of unalloyed amorphous Ru oxide, with only about 1-2 % of the Ru alloyed with Pt. The analysis of methanol oxidation showed that the mass specific activity of Pt-Ru/S0 electrocatalyst was 1790 mA·mgPt-1, with a 23 % increase than that of Pt-Ru/CB electrocatalyst and a 110 % increase than that of Pt/S0 electrocatalyt. Among the all electrocatalysts, the Pt-Ru/SKN electrocatalysts showed the most highly catalytic activity for the oxidation of methanol. The activity of Pt-Ru/GPCSP electrocatalysts increased slightly after the thermal treatment at 300℃; while after thermal treatment at 900℃, its activity decreased obviously.The atomic compostions for 10 wt(Pt+Co)% Pt-Co/GPCSP electrocatalysts were nearly 80:20. But there was a large excess of unalloyed amorphous Co oxide, with only about 3-4 % of the Co alloyed with Pt. The analysis of methanol oxidation showed that the mass specific activity of Pt-Co/S0 electrocatalyst was 2010 mA·mgPt-1, with a 20 % increase than that of Pt-Co/CB electrocatalyst and a 136 % increase than that of Pt/S0 electrocatalyt. Among the all electrocatalysts, the Pt-Co/SKN electrocatalysts showed the most highly catalytic activity for the oxidation of methanol. The activity of Pt-Co/GPCSP electrocatalysts increased slightly after the thermal treatment at 300℃; while after thermal treatment at 900℃, its activity decreased obviously.
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