A single palladium (Pd) atom embedded in a high curvature defective carbon nanocone (Pd/dCNC) is investigated for formic acid (FA) decompositions using DFT calculations. We used Pd/dCNC as the catalyst for either trans-FA or cis-FA decomposition. FA is stably adsorbed on Pd/dCNC with very high adsorption energy compared to the Pd/dG surface. For the reaction mechanisms, the preferable FA dehydrogenation mechanisms proceed via the formate pathway, with a rate-determining step of only 0.50 eV (trans-FA) and 0.54 eV (cis-FA), which are less than that on active Pd (111) catalysts. The rate of hydrogen (H₂) production is dependent on the FA concentration. The active neighboring C atom plays a significant role in facilitating FA dehydrogenation into H₂. The side reaction producing CO and H₂O via the formyl or carboxyl pathway cannot occur on Pd/dCNC due to a high energy-barrier and low production rate obtained by microkinetic simulations. Thus, our proposed catalysts effectively provide excellent activity and selectivity for FA dehydrogenation into H₂.

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用于制氢的单原子 Pd 沉积碳纳米锥上的甲酸脱氢：机械 DFT 研究

使用 DFT 计算研究了嵌入高曲率缺陷碳纳米锥 (Pd/dCNC) 的单个钯 (Pd) 原子的甲酸 (FA) 分解。我们使用 Pd/dCNC 作为反式-FA或顺式-FA 分解的催化剂。与 Pd/dG 表面相比，FA 以非常高的吸附能稳定吸附在 Pd/dCNC 上。对于反应机制，优选的 FA 脱氢机制通过甲酸途径进行，限速步骤仅为 0.50 eV（反式-FA）和 0.54 eV（顺式-FA），低于活性 Pd（111 ) 催化剂。氢（H ₂) 产量取决于 FA 浓度。活性相邻的 C 原子在促进 FA 脱氢成 H ₂方面起着重要作用。由于微动力学模拟获得的高能量屏障和低产率，通过甲酰基或羧基途径产生 CO 和 H ₂ O的副反应不会发生在 Pd/dCNC 上。因此，我们提出的催化剂有效地为 FA 脱氢成 H ₂提供了优异的活性和选择性。