微波電漿處理鐵鈷/鈦纖維紙用於陰離子交換膜水電解模組

Abstract

在淨零趨勢下，水電解為綠氫製備關鍵技術；其中陰離子交換膜水電解（Anion Exchange Membrane Water Electrolysis, AEMWE）具可使用非貴金屬催化劑等優勢，但陽極析氧反應（Oxygen Evolution Reaction, OER）動力學緩慢，常成為效率瓶頸，因此開發高效且可量產的OER催化劑相當重要。 本研究以電化學沉積法在鈦纖維紙（Titanium fiber Paper, TP）上沉積鐵鈷合金，製備ED-FeCo/TP，作為陰極乾端操作之AEMWE系統中的析氧反應OER陽極電催化劑。進一步施以15秒的氬氣微波電漿（Ar Microwave Plasma, ArMP）表面處理，其催化表現顯著提升。經處理之ED-FeCo/TP-ArMP15在100 mA/cm2電流密度下之過電位僅459 mV，並呈現較佳的塔弗斜率（211.1 mV/dec），顯示反應動力學獲改善；同時其電雙層電容Cdl提升至2.80 mF/cm2，電荷轉移阻抗（Rct）降至1.10 Ω，反映出更大的有效活性表面積與更快速的界面電荷傳輸。 材料分析結果指出，氬氣微波電漿處理具還原效應，可在ED-FeCo/TP-ArMP15中形成大量金屬態Fe0與Co0活性位點。進一步將其應用於陰極乾式陰離子交換膜水電解全電池中可發現，採用氬氣微波電漿之系統（Ru/CP(−) // ED-FeCo/TP-ArMP15(+)）在高電流密度操作下，相較未經氬氣微波電漿處理之系統（Ru/CP(−) // ED-FeCo/TP(+)）具有更佳之性能表現。於70 ℃、500 mA/cm2操作條件下，當ED-FeCo/TP作為陽極時，電池電壓由1.88 V降至1.79 V（ED-FeCo/TP-ArMP15），進一步驗證氬氣微波電漿能有效提升OER效率。

Under the global net-zero transition, water electrolysis is essential for green hydrogen production. Anion exchange membrane water electrolysis (AEMWE) enables the use of non-precious-metal catalysts, yet its efficiency is often limited by sluggish anodic oxygen evolution reaction (OER) kinetics, highlighting the need for active and scalable OER catalysts. ED-FeCo/TP is synthesized by the electrochemical deposition of FeCo on titanium fiber paper (TP) as the catalyst for the OER in cathode-dry operation AEMWE. With 15s Ar microwave plasma (ArMP) treatment, the catalytic performance is enhanced. The ED-FeCo/TP treated with ArMP (ED-FeCo/TP-ArMP15) exhibits a lower overpotential (459 mV@100 mA/cm2) and improved Tafel slope (211.1 mV/dec), indicating improved reaction efficacy. It also demonstrates a higher double-layer capacitance (2.80 mF/cm2), lower charge transfer resistance (1.10 Ω), and enhanced electrochemical activity. ArMP treatment provides a reduction effect, leading to the formation of abundant metallic Fe0 and Co0 in ED-FeCo/TP-ArMP15. The cathode-dry AEMWE system with ArMP treatment (Ru/CP(-) // ED-FeCo/TP-ArMP15(+)) exhibits better performance at higher current densities than the system without ArMP treatment (Ru/CP(-) // ED-FeCo/TP(+)). When applied as the anode in a cathode-dry AEMWE system operating at 70 ℃, the cell voltage at a current density of 500 mA/cm2 decreases from 1.88 V for ED-FeCo/TP to 1.79 V for ED-FeCo/TP-ArMP15. These results indicate that ArMP treatment effectively enhances the OER efficiency.