Inert CO₂ is only physically adsorbed on the surface of h-BN and graphene two-dimensional (2D) materials. However, a Si-doped h-BN sheet is able to capture CO₂ directly through chemisorption under mild conditions. Herein, first-principles calculations and ab initio molecular dynamics (AIMD) simulations have been performed to explore the interaction between CO₂ and the Si-doped h-BN sheet, and CO₂ activation and chemisorption at the SiN₃ site are predicted to be exothermic (−0.22 eV) and almost barrier free (0.03 eV). Such high activity of the single Si site toward CO₂ activation strongly depends on its local bonding environment, and there are only weak van der Waals interactions between CO₂ and SiB₃ and SiC₃ units of Si-doped h-BN and graphene sheets. The present calculations reveal that the Si-p_z dangling bond dominates the Si–CO₂ bonding interaction in CO₂ chemisorption on the Si-doped h-BN sheet, and facile activation and capture of CO₂ require the low-energy p_z band of Si.

中文翻译：

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Si掺杂的h-BN薄板上的CO ₂活化和捕获：洞悉单个Si位点的局部键合效应

惰性CO ₂仅物理吸附在h-BN和石墨烯二维（2D）材料的表面上。然而，掺Si的h-BN片能够在温和条件下通过化学吸附直接捕获CO ₂。本文中，已经进行了第一性原理计算和从头算分子动力学（AIMD）模拟，以探索CO ₂与掺Si的h-BN薄板之间的相互作用，并预测在SiN ₃位置处的CO ₂活化和化学吸附是放热（-0.22 eV），几乎无障碍（0.03 eV）。单个Si位点对CO _2的如此高的活性活化很大程度上取决于其局部键合环境，并且在掺Si的h-BN和石墨烯片材的CO ₂与SiB ₃和SiC ₃单元之间只有弱的范德华相互作用。目前的计算表明，Si-p _z悬空键在掺杂Si的h-BN片材上的CO ₂化学吸附中主导了Si-CO ₂键相互作用，并且容易激活和捕获CO ₂要求低能p _z谱带的Si。