通过第一性原理计算,研究在CO或SO2存在下,廉价金属Fe掺杂六方氮化硼(Fe-BN)对N2O还原反应的催化性能。从吸附构型与电子性质分析,发现N2O在Fe-BN的表面自发解离,这是衬底和N2O之间大量电荷转移所致,对N2O的吸附能也远大于CO或SO2,将有利于反应的进行。计算CO、SO2和N2O与O*的反应能垒分别为0.52 eV、1.06 eV和2.61 eV,N2O的反应能垒最高,表明此反应不会发生。Fe-BN对反应产物CO2的吸附较弱,通过反应过程释放的能量便可完成解吸,而反应产物SO3则不能,可见CO作为还原剂更有利。由此得出,Fe-BN是还原N2O的高活性催化剂。本研究为低成本、高活性的基于廉价金属掺杂六方氮化硼催化剂的开发开辟了新的途径。

Based on the first principle calculation, the catalytic performance of a cheap metal Fe doped hexagonal boron nitride (Fe-BN) for N2O reduction in the presence of CO or SO2 was studied. From the analysis of the adsorption configurations and electronic properties, it was found that the spontaneous dissociation of N2O on the surface of Fe-BN was caused by a large amount of charge transfer between the substrate and N2O. The adsorption energy of N2O was much greater than that of CO or SO2, which would be conducive to the reaction. The reaction energy barriers of CO, SO2 and N2O with O* were calculated to be 0.52 eV, 1.06 eV and 2.61 eV, respectively. The reaction energy barrier of N2O was the highest, indicating that this reaction could not occur. The adsorption of the reaction product CO2 by Fe-BN was weak, and the energy released through the reaction process could satisfy the desorption of CO2, while the desorption of SO3 could not occur. So it can be seen that CO is more favorable as a reducing agent. It is concluded that Fe-BN is a highly active catalyst for N2O reduction. This study opens up a new way for the development of low-cost and highly active catalysts based on low-cost metal doped hexagonal boron nitride.