| 摘要: | 高熵合金領域至今僅研究二十餘年，還有很多製程與應用方向待開發，本研究以高熵合金的理論基礎開發了一系列製程，名為金屬鹽類雷射加工技術。
本製程研究主軸以脈衝式光纖雷射施打於硝酸根前驅物之CoCrFeNiAl金屬鹽類產物為主，其產物為高熵陶瓷奈米粒子膜，為此新興材料進行一系統性的參數測試，並加以分析與應用，並且嘗試用不同金屬鹽類前驅物及不同基板來顯示此製程擁有操作簡單、可快速製造、高比表面積、產品設計自由度高與可圖案化等特點。
製程中變動參數組合為雷射重複掃描次數、前驅物容積、前驅物鹽類種類以及基材種類，將成品進行一系列的分析如電子顯微鏡之顯微結構、X光繞射分析儀、X光光電子光譜儀之元素成分及與晶體結構分析，重複驗證高熵陶瓷奈米粒子膜之材料特性及趨勢。
同步輻射之XRD分析證明出此材料為尖晶石結構之高熵陶瓷奈米粒子，A3O4（A = Co，Cr，Fe，Ni或Al）尖晶石結構中A site或B site可被其他元素佔據，所以此製程可以使二價或三價金屬填入於尖晶石中，這將會影響高熵陶瓷奈米粒子之催化之傳統結構印象。
利用其製程技術製造電催化電極，將硝酸根CoCrFeNiAl前驅物反應於氧化銦錫基板及泡沫金屬基材，於電解液中進行OER產氧反應，皆獲得優異的電流密度輸出與大幅降低反應過電位，並於穩定性量測中皆獲得超過10天以上的壽命。另外提高電催化活性與穩定性之測試，400 mA/cm2是工業應用的標準電流要求，我們的CoCrFeNiAl HEC 可以在如此高的電流密度下運行超過 150 小時而不會出現明顯衰減。
最後基於碳材和高熵協同效應，研究探討結合碳材吸附、電催化反應、氧還原反應及芬頓技術應用於水中汙染物之降解研究，將主軸高熵陶瓷奈米催化粒子長於碳材上，使汙水得到有效處理，此系統成功地證明了在運行 90 分鐘內可去除100% 的甲基橙(MO)。並在開放式循環式系統中，150分鐘可以完全降解三倍封閉式水量。;The field of high-entropy alloys has been studied for only about twenty years, and there are still many manufacturing processes and application directions to be developed. Our research has developed a series of processes based on the theoretical basis of high-entropy alloys, called pulsed-laser-irradiation scanning on mixed-salt solutions.
The product of our process is high-entropy ceramic nanoparticle film. The main objective of our research is mainly the CoCrFeNiAl metal salt product of the nitrate precursor. For this emerging material, a systematic parameter tests are carried out, analyzed and applied, showing that there are the characteristics of simple operation, fast manufacturing, low cost, high specific surface area, high product design freedom and ability of pattern.
The combination of variable parameters in the process is the number of laser repetitive scans, the volume of the precursor, the type of precursor salt, and the type of substrate. The finished product is performed a series of analysis, such as the microstructure of the electron microscope, X-ray diffractometer (XRD), X-ray photoelectron spectrometer (XPS) for elemental composition and crystal structure analysis of the photoelectron spectrometer to repeatedly verified the material characteristics and trends of the high-entropy ceramic nanoparticle film.
XRD analysis of synchrotron radiation proves that this material is a high-entropy ceramic nanoparticle with a spinel structure, A3O4、AB2O4（A, B = Co, Cr, Fe, Ni or Al）. A site and B site in the spinel structure can be replaced by other elements, so divalent or trivalent metals can be occupied in the spinel by this process, which will affect the traditional structure impression of high-entropy ceramic nanoparticle catalysis.
On the other hand, high-entropy ceramics were fabricated to improve both the electrocatalytic activity and stability. 400 mA/cm2 is a standard current requirement for the industrial application and our CoCrFeNiAl HECs can run under such high current density for more than 150hrs without obvious decay.
Due to the synergistic effect between the functionalized carbon and high-entropy ceramics (HECs), this closed system successfully demonstrated a 100% removal of Methyl Orange (MO)within 90 minutes of operation, and the open circulation system demonstrated a 100% removal of Methyl Orange (MO) within minutes of 150 operation. |
