Junaid Muhammad, Karam Sajid, Iqbal Muhammad, Anjum Mehran
Department of Chemistry, University of Malakand, Chakdara, Pakistan.
J Mol Model. 2025 Jun 28;31(7):201. doi: 10.1007/s00894-025-06425-5.
The industrial production of ammonia through the Haber-Bosch process is energy intensive and operates under extreme conditions. In contrast, the catalytic reduction of nitrogen (N₂) to ammonia (NH₃) under mild conditions presents a significant challenge with important implications for sustainable chemistry. This work investigates the potential of Mo-doped carbon nitride (C₄₂N₂₄) fullerene as a catalyst for N₂ reduction. The study reveals that Mo@C₄₂N₂₄ exhibits rapid catalytic activity, with a preference for the enzymatic mechanism for N₂ conversion to NH₃. Notably, H₂ evolution is suppressed, making Mo-doped C₄₂N₂₄ a promising candidate for ammonia synthesis under mild conditions.
Density functional theory (DFT) calculations were performed using the Perdew-Burke-Ernzerhof (PBE) functional within the generalized gradient approximation (GGA) framework. The DNP basis set was employed in all calculations using the DMol code. The Mo atom was incorporated into the N₄ cavity of the carbon nitride structure, with a binding energy of - 2.54 eV. The electronic structure was analyzed through molecular electrostatic potential maps, Hirshfeld charge density analysis, and spin density analysis. Three catalytic pathways, alternating, distal, and enzymatic were studied to understand the reaction mechanism. All calculations were carried out using the DMol software package.
通过哈伯-博施法进行氨的工业生产能源密集且在极端条件下运行。相比之下，在温和条件下将氮气（N₂）催化还原为氨（NH₃）面临重大挑战，对可持续化学具有重要意义。这项工作研究了钼掺杂的氮化碳（C₄₂N₂₄）富勒烯作为N₂还原催化剂的潜力。研究表明，Mo@C₄₂N₂₄表现出快速的催化活性，倾向于将N₂转化为NH₃的酶促机制。值得注意的是，氢气的析出受到抑制，使得钼掺杂的C₄₂N₂₄成为在温和条件下合成氨的有前景的候选材料。
使用广义梯度近似（GGA）框架内的佩德韦-伯克-恩泽霍夫（PBE）泛函进行密度泛函理论（DFT）计算。在所有计算中使用DMol代码采用DNP基组。将钼原子掺入氮化碳结构的N₄空腔中，结合能为-2.54 eV。通过分子静电势图、赫希菲尔德电荷密度分析和自旋密度分析来分析电子结构。研究了交替、远端和酶促三种催化途径以了解反应机理。所有计算均使用DMol软件包进行。
