本研究藉由脈衝式電化學沉積法在乾淨碳紙上製備新型態鉑觸媒作為質子交換膜燃料電池之觸媒。此新型態鉑觸媒之特殊形貌可增加觸媒反應活性，在不使用其它碳載體的情況下具有較多的觸媒表面積，進而提升觸媒催化效率及電池輸出功率。經由循環伏安法於硫酸及甲醇溶液下進行電化學測試，並利用X光粉末繞射儀(XRD)、掃描式電子顯微鏡(SEM)、穿透式電子顯微鏡(TEM)以及電感耦合等離子體質譜(ICP-MS)對試片做進一步的分析。透過掃描式電子顯微鏡照片發現此新型態鉑觸媒的結構為樹枝狀結構，其主幹長度約為數百奈米至3 μm，而寬度約為200至450 nm。半電池電化學測試結果顯示，甲醇測試峰電流值可達585.6 mA/cm2，其if/ib值超過1.4，顯示鉑樹枝狀結構觸媒具有良好的抗一氧化碳毒化能力。使用最佳參數製備出的鉑樹枝狀觸媒再經由氫氣單電池測試，其功率密度可達1140 mW/cm2，顯示鉑樹枝狀觸媒具有高催化性。

Innovative platinum (Pt) nanostructures were developed in this study for enhancing the catalyst activities and the power density of single cell for proton exchange membrane fuel cell (PEMFC) application. The platinum nanostructures were directly grown on carbon paper by a pulsed electrodeposition technique. The morphology of Pt nanostructures were investigated by SEM, and shown as dendritic structures instead of nanoparticles. The sizes of the dendritic structures were a few nanometers to 3 m in length and 200~450 nm in diameter. A cyclic voltammetry analysis was carried out for characterizing the behavior of methanol oxidation on specimen bearing the Pt dendritic nanostructures in a mixed electrolyte of 1 M methanol and 0.5 M sulfuric acid. It was found that the peak current density of methanol oxidation on the new Pt dendritic nanostructures was as high as 586.5 mA/cm2. The Pt dendritic nanostructures could exhibit a good carbon monoxide tolerance and high efficiency without the incorporation of ruthenium (Ru) catalyst. Based upon the single cell tests, the peak specific power density of PEMFC with the homemade dendritic Pt catalyst was 1140 mW/cm2 and greater than one with the commercial catalysts. The outcome signified a nanostructure catalyst morphology and a significantly improved catalytic activity of the anode or cathode prepared by a pulsed electrodeposition technique.

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