| Summary: | 碩士 === 國立臺北科技大學 === 資源工程研究所 === 103 === The direct alcohol fuel cell (DAFC) generated high energy densities by using liquid fuel, and is regarded as a potential option to achieve widely acceptable commercial products.The anode composite catalysts of DAFC are often prepared by polyol reduction process, and the performance of electrocatalytic alcohol oxidation and anode durability could be improved by choosing optimum catalysts and supports.This study focused on the effect of adding silicon carbide to Pt@C catalysts on electrocatalytic alcohol oxidation. The recovered SiC-rich powders from silicon slurry waste were also used as supports to prepare composite catalysts. The feasibility of using various supports and the electrooxidation performance of methanol or ethanol were reported in this work. Herein, Pt@C, Pt@SiC, and Pt@C-SiC catalysts were synthesized with polyol reduction process, and SiC supports were from commercial products and the recovered powders from silicon slurry waste. The experimental results show that nano-sized Pt particles could be reduced on C, SiC or C-SiC supports, and higher electrochemically active surface areas could be obtained by using Pt@C and Pt@C-SiC than Pt@SiC. The results of electrochemical analysis showed the alcohol electrooxidation performance were higher using Pt@C-SiC than Pt@C or Pt@SiC, and Pt@C-SiC catalysts also exhibited higher electrochemical stability, In addition, the performance with 1 μm SiC was better than that with 10μm SiC, and was close to that with the recovered SiC-rich powders, some in ratios especially. The impedance results showed that there were great differences in curves by using Pt@C-SiC compared with using Pt@C or Pt@SiC, indicating the different reaction mechanisms between using one support and using mixed supports. At low potential, the transport and reactions of materials on Pt@C-SiC involved passing C and SiC, resulting in complex impedance. When the potential increased, the transport and reactions of materials were similar via passing C or SiC. The study demonstrated that adding silicon carbide to Pt@C catalysts improved the performance of electrocatalytic alcohol oxidation and anode durability. Also we applied the concept of waste-to-resource to electrocatalytic alcohol composite catalysts by the recovered materials from silicon slurry waste.
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