在第一小節中，本研究採用密度泛函理論 (Density Functional Theory, DFT)計算，在B3LYP-D3/def2-SVP 理論水平下利用 ORCA 6 軟體進行幾何結構優化與內在反應座標 (Intrinsic Reaction Coordinate, IRC)路徑追蹤。進一步透過內在鍵軌域 (Intrinsic Bond Orbital, IBO)的分析技術，將電催化氮氣還原反應 (electrochemical nitrogen reduction reaction, N2ER)過程中的電子轉移可視化。氫化步驟的六個動態階段中，可直觀觀察當水分子靠近氮原子時，氮原子上的孤對電子會主動捕捉質子，從而形成新的 N-H 鍵。大部分中間體的氫化步驟高度依賴於其孤對電子軌域，使得提升中間體鹼性，也就是提升孤對電子軌域的活性成為促進還原反應的核心策略。
在第二小節中，本研究構建了釕基過渡金屬模型（TM@Ru）。該模型主要基於Ru(0001)晶面，將將過渡金屬原子（TM）摻雜於其表面，利用VASP軟體進行週期性DFT計算。本研究將Surface pKa理論框架拓展至TM@Ru體系，並引入∆pKa來評估摻雜金屬對N2ER 各個質子化步驟的效果。經由氮氣吸附自由能與第一步質子化能力的雙重篩選，選定 V@Ru 、Cr@Ru 與Mn@Ru作為具備高潛力的核心催化材料。為了更真實地模擬電化學環境，本研究進一步結合恆定電位修正法，評估不同電壓下在末端、交替及混合路徑中的活性表現。結果表明，儘管各路徑受限於不同的中間體，但過渡金屬的摻雜在垂直與水平吸附構型下皆能提升N2*的鹼性，克服了首步氫化這一電位決定步驟的限制，為高效N2ER催化劑的設計提供了創新的調控策略。

In the first section, density functional theory (DFT) calculations were performed using the ORCA 6 software at the B3LYP-D3/def2-SVP level of theory to conduct geometric structure optimization and intrinsic reaction coordinate (IRC) pathway tracking. Furthermore, the intrinsic bond orbital (IBO) analysis technique was utilized to visualize the electron transfer processes during the electrochemical nitrogen reduction reaction (N2ER). Across the six dynamic stages of the hydrogenation steps, it can be intuitively observed that as a water molecule approaches a nitrogen atom, the lone pair electrons on the nitrogen atom actively capture a proton, thereby forming a new N–H bond. The hydrogenation steps for most intermediates are highly dependent on their lone pair orbital activity, rendering the enhancement of intermediate basicity, increasing the activity of the lone pair electron orbital.
In the second section, to address the bottlenecks of pure ruthenium surfaces, which are limited by competitive reactions and the difficulty of nitrogen activation, periodic DFT calculations were conducted using the VASP software on on TM@Ru (TM = Fe, Co, Ni, Cu, etc) models.Through a dual-screening process based on nitrogen adsorption free energy and the capability of the initial protonation step, V@Ru, Cr@Ru, and Mn@Ru were selected as core catalytic materials with high potential. This study further incorporates constant potential corrections to evaluate the activity performance along the distal, alternating, and mixed pathways under different applied voltages. The results indicate that while each pathway is limited by different intermediates, transition metal doping enhances the basicity of N2* in both end-on and side-on adsorption configurations. This overcomes the limitation of the first hydrogenation step as the potential-determining step, providing an innovative tuning strategy for the design of high-efficiency N2ER catalysts.

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