本實驗利用脈衝式沉積法製備銥觸媒於多壁奈米碳管 (Muti-walls carbon nanotubes, MWCNT) 載體上，並應用於質子交換膜水電解器 (Proton exchange membrane water electrolyzer, PEMWE) 的陽極端。但由於 PEMWE 陽極端於高過電位 (>1.48 V) 下進行，因此大多數觸媒載體並不適用，使增加了陽極端貴重金屬的負載量。而奈米碳管擁有高機械強度、抗化學性以及高導電度，因此廣泛被作為觸媒載體，相較於傳統碳黑載體，有較佳的抗腐蝕能力，因此將其應用於 PEMWE 的陽極端。
掃描式電子顯微鏡 (Scanning electron microscopy, SEM)、循環伏安法 (Cyclic voltammetry, CV)、線性掃描伏安法 (Linear sweep voltammetry, LSV) 和感應耦合電漿質譜分析儀 (Inductively coupled plasma-mass spectrometer, ICP-MS) 以及 X-光繞射儀 (X-ray Diffractometer, XRD) 用以測試觸媒表面形貌、活性和負載量以及商用觸媒的晶體結構，最後經由 PEMWE 測試產氫效率以及長效測試。在 PEMWE 測試中，透過脈衝式沉積銥觸媒於奈米碳管上，水電解效率於 1 A/cm2 有 1.625 V，且觸媒負載量只有 0.167 mg/cm2。
另外，本實驗也同時探討了商用氧化銥 (Iridium oxide) 應用於 PEMWE 陽極端的電解效率，並和自製觸媒做比較。經過參數優化後，結果顯示電解效率於 1 A/cm2 僅 1.73 V。最後，耐久性測試中發現利用脈衝式電鍍於奈米碳管載體 (CNT@Ir) 相較於商用觸媒 (IrO2) 擁有穩定的降解效率。

This experiment utilizes the pulse electrodeposition method to prepare iridium catalyst on multi-wall carbon nanotubes (MWCNT) as a support, which is then applied to the anode side of a proton exchange membrane water electrolyzer (PEMWE). However, due to the high operating potential (>1.48 V) at the anode side of PEMWE, most catalyst supports are not suitable, resulting in an increased loading of precious metals at the anode side. On the other hand, carbon nanotubes have high mechanical strength, chemical resistance, and conductivity, making them widely used as catalyst supports. Compared to traditional carbon black supports, they exhibit superior corrosion resistance, thus making them suitable for application at the anode side of PEMWE.
The surface morphology, activity, loading, and the crystal structure of commercial catalysts were characterized by SEM, CV, LSV, ICP-MS, and X-ray diffractometer (XRD). Finally, the catalyst was tested through PEMWE to evaluate its hydrogen production efficiency and durability. In PEMWE testing, the iridium catalyst was pulse-deposited on carbon nanotubes, resulting in electrolysis efficiency of 1.625 V at 1 A/cm2, with a catalyst loading of only 0.167 mg/cm2.
Additionally, the electrolysis efficiency of commercial iridium oxide (IrO2) applied to the anode side of PEMWE was also investigated and compared with a homemade catalyst. After parameter optimization, the results showed that the electrolysis efficiency at 1 A/cm2 was only 1.73 V. In the durability test, it was found that the catalyst prepared using pulse electrodeposition on a carbon nanotube support (CNT@Ir) exhibited a more stable degradation efficiency compared to the commercial catalyst.

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