Anthony J. R. Payne, Neubi F. Xavier, Marco Sacchi
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引用次数: 0
Abstract
Sustainable catalysts are essential for critical industrial and environmental processes. 2D materials have exceptional surface area and unique thermal and electronic properties, making them excellent candidates for catalytic applications. Moreover, 2D materials can be functionalised to create metal-free active sites, which provide sustainable alternatives to transition and precious metals. Among the pollutants emitted by combustion engines, NOx stands out as one of the most detrimental gases, contributing to environmental pollution and posing risks to human health. We demonstrate that functionalised defects in hexagonal boron nitride (hBN) provide a thermodynamically viable route to removing NOx by reaction with a hydrogenated boron vacancy (3HVB). The decomposition of NO2 proceeds by initially overcoming an activation energy barrier of 1.12 eV to transfer a hydrogen atom from the surface, forming a NO2H species, followed by the elimination of a water molecule. A thermodynamically favourable product consisting of a surface-bound hydroxyl adjacent to a nitrogen antisite defect (where a nitrogen atom occupies a site typically occupied by a boron atom) forms after overcoming an energy barrier of 1.28 eV. NO can further decompose by overcoming an activation energy barrier of 2.23 eV to form a surface HNO species. A rearrangement of the HNO species takes place with an activation energy of 1.96 eV, followed by the elimination of water. The overall reactions reduce NOx into defective hBN and H2O.
期刊介绍:
A multidisciplinary journal focusing on cutting edge research across all fundamental science and technological aspects of catalysis.
Editor-in-chief: Bert Weckhuysen
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