| 摘要: | 氫能作為一種潔淨且永續的替代能源，受到廣泛的關注。傳統的水分解反應通常在額外添加電解質的淡水中進行，然而淡水資源短缺，已成為氫能大規模應用的重大挑戰。近年來，海水電解逐漸被視為一具潛力的永續產氫策略，然而，其實際應用仍面臨諸多挑戰，包括鹽類沉積與高腐蝕性等關鍵問題，急需有效解決以實現海水電解的應用。
本研究設計並製備了用於0.5 M H2SO4與鹼性模擬海水中的高效析氫反應(hydrogen evolution reaction, HER)電催化觸媒，以金屬有機框架(metal-organic frameworks, MOFs)衍生物作為載體，構築了釕(Ru)為主的催化系統。其中，選用Ni-BTC(1,3,5-苯三甲酸，H3BTC)作為基材，因其多孔結構可提供大量活性位點，具備優異的結構穩定性與快速的離子傳導能力，可有效提升HER活性。透過策略性地引入鉑(Pt)與均勻分散的鎳(Ni)，調節氫吸附能並促進反應動力學。其中RuPt0.3@Ni/C與Ru@Ni/C在酸性與鹼性模擬海中皆展現出優異的性能，在電流密度10 mA cm-2下的過電位(η10)分別僅為25和14 mV，Tafel斜率分別為14和33 mV dec-1，質量活性分別高達527和596 A g⁻¹ Ru+Pt。
為深入探討觸媒的催化機制，進行了臨場X光吸收光譜(in-situ X-ray absorption spectroscopy, XAS)分析，以解析HER過程中的活性位點，同時利用電感耦合電漿發射光譜(inductively coupled plasma optical emission spectrometry, ICP-OES)評估穩定性測試後觸媒的金屬殘留率。此外，透過CO剝離(CO-stripping)實驗，進一步揭示了鹼性模擬海水中的水解離行為。臨場XAS與ICP-OES實驗結果證實，Ni-BTC衍生物載體提供穩定的結構，能有效抑制Cl-誘發的腐蝕反應並防止反應過程中金屬的溶解。CO剝離實驗結果進一步表明，適量引入Pt可調節氫吸附能，從而促進水解反應並提升HER活性。本研究成果為開發高效能HER觸媒與海水產氫技術提供了可行的設計策略與理論依據。;Hydrogen energy has attracted significant attention as a clean and sustainable alternative energy source. Tractional water splitting is typically conducted in freshwater with added electrolytes. However, the limited availability of freshwater poses a major challenge for the large-scale implementation of hydrogen energy. Recently, seawater electrolysis has emerged as a promising strategy for continuous hydrogen production. Nonetheless, critical challenges such as salt precipitation and high corrosiveness must be addressed to realize its full potential.
In this study, efficient Ru-based electrocatalysts supported on metal-organic frameworks (MOFs)-derived structures were prepared for the hydrogen evolution reaction (HER) in both 0.5 M H2SO4 and alkaline simulated seawater. The Ni-BTC (1,3,5-benzenetricarboxylic acid, H3BTC)-derived support provides a porous structure with abundant active sites, excellent structural stability, and rapid ion transport, all of which enhance HER activity. Strategic incorporation of Pt and well-dispersed Ni modulates hydrogen adsorption energy and accelerates reaction kinetics. Notably, RuPt0.3@Ni/C and Ru@Ni/C catalysts exhibit remarkable performance in acidic and alkaline simulated seawater media, achieving overpotentials of 25 and 14 mV at 10 mA cm-2, Tafel slopes of 14 and 33 mV dec-1, and mass activities of 527 and 596 A g-1 Ru+Pt, respectively.
To elucidate the catalytic mechanisms, in situ X-ray absorption spectroscopy (XAS) was performed to clarify the active sites during the HER process, while inductively coupled plasma optical emission spectrometry (ICP-OES) was used to evaluate metal retention during stability tests. The CO-stripping analysis further provides insights into water dissociation behavior in alkaline simulated seawater media. In-situ XAS and ICP-OES results confirm that the Ni-BTC-derived support offers a structurally stable framework, effectively mitigates Cl- induced corrosion, and prevents the dissolution of metals during the HER process. Additionally, CO-stripping experiments demonstrate that the moderate incorporation of Pt modulates hydrogen adsorption energy, thereby facilitating water dissociation and enhancing HER performance. These findings offer a practical design strategy for high-performance HER catalysts and advancing seawater-based hydrogen energy technologies. |
