Furmaniak Sylwester, Gauden Piotr A, Patrykiejew Andrzej, Miśkiewicz Radosław, Kowalczyk Piotr
Stanisław Staszic University of Applied Sciences in Piła, Podchorążych Street 10, 64-920, Piła, Poland.
Physicochemistry of Carbon Materials Research Group, Faculty of Chemistry, Nicolaus Copernicus University in Toruń, Gagarin Street 7, 87-100, Toruń, Poland.
Sci Rep. 2018 Oct 18;8(1):15407. doi: 10.1038/s41598-018-33725-z.
Carbon nanohorns (CNHs, one of the newest carbon allotropes) have been subjected to intensive experimental and theoretical studies due to their potential applications. One of such applications can be their use as reaction nanochambers. However, experimental studies on the reaction equilibria under confinement are extremely challenging since accurate measurements of the concentrations of reacting species in pores are a very hard task. So, the main ways to examine such phenomena are theoretical methods (e.g. the reactive Monte Carlo, RxMC). We have presented the first systematic RxMC study on the influence of the CNH's geometric parameters (the apex angle, the diameter, and the length) on reaction equilibria, taking the nitrogen monoxide dimerisation as an example. All the investigated parameters significantly affect the reaction yield at low and moderate coverages. Short and narrow CNHs have been found to be preferred. However, the key factor influencing the reaction equilibria is the presence of a conical part. Energetics of interactions between the reacting molecules in this fragment of a nanohorn maximises the effects of confinement. In consequence, CNHs have the advantage over their nanotube counterparts of the same diameter. The obtained results have confirmed that CNHs can be considered as potential reaction nanochambers.
碳纳米角（CNHs，最新的碳同素异形体之一）因其潜在应用而受到了深入的实验和理论研究。此类应用之一可能是将其用作反应纳米腔。然而，由于精确测量孔内反应物的浓度是一项非常艰巨的任务，因此对受限条件下的反应平衡进行实验研究极具挑战性。所以，研究此类现象的主要方法是理论方法（例如反应蒙特卡罗方法，RxMC）。我们以一氧化氮二聚反应为例，首次对碳纳米角的几何参数（顶角、直径和长度）对反应平衡的影响进行了系统的反应蒙特卡罗研究。在低覆盖率和中等覆盖率下，所有研究的参数都会显著影响反应产率。已发现短而窄的碳纳米角更具优势。然而，影响反应平衡的关键因素是锥形部分的存在。纳米角这一部分中反应分子间相互作用的能量学使受限效应最大化。因此，与相同直径的纳米管相比，碳纳米角具有优势。所得结果证实，碳纳米角可被视为潜在的反应纳米腔。
