| Summary: | 碩士 === 大同大學 === 材料工程學系(所) === 101 === Electric catalysts are easily poisoned by CO adsorption in oxidation of methanol and formic acid that will lead to decrease the performances of catalysts. In this study, the metal oxides are introduced and coated on the MWCNTs to prevent CO poison the electro catalysts, and to improve catalyst activity and stability. Hybrid Oxides/ MWCNTs are synthesized by two different methods: chemical reduction method and impregnation method. Noble metals (Platinum, Pt or Palladium, Pd) are synthesized by polyol method to deposit on the MWCNTs or Oxide/MWCNTs.
In Pt-series electrocatalysts, the catalytic effect by adding different oxides such as indium oxide (In2O3), tin (IV) oxide (SnO2) and indium tin oxide (ITO) on the surface of MWCNTs are examined. The results of electrochemical analysis that indicate electrocatalytical activity can be enhanced more than that of Pt/MWCNTs by adding metal oxide. In addition, Pt/In2O3/MWCNTs electrocatalysts have the highest catalytic active.
In Pd-series electrocatalysts, three different electrocatalysts (Pd/In2O3/MWCNTs, Pd/SnO2/MWCNTs and Pd/MWCNTs) are compared the electrooxidation performance of formic acid. In2O3/MWCNTs are synthesized by chemical reduction method. This method can enhance the dispersion of In2O3 nanoparticles on the surface of MWCNTs. After Pd deposition, InPd2 structure is observed in XRD analysis. The electrochemical results indicate Pd/In2O3/MWCNTs electrocatalysts have higher active than those of Pd/SnO2/MWCNTs and Pd/MWCNTs.
Summarize the results of this study, metal catalysts deposited on In2O3 modified MWCNTs have better catalytic property than those other supports. The addition of In2O3 enhances the oxidation of the carbon monoxides that absorb on the surface of Pt electrocatalysts; it can prevent CO poison of electrocatalysts. Thus, it will enhance the efficiency of anode materials in fuel cell applications by adding In2O3.
|
|---|
