摘要
Ethane dehydrogenation(EDH)to produce ethylene requires high operating temperature to achieve satisfactory ethylene yield,however,this process leads to coke formation and catalyst deactivation.Here,an active site isolation strategy was employed to inhibit side reaction and coke formation over fifteen types of metal single-atom metal/graphitic carbon nitride(M/g-C_(3)N_(4))catalysts.Density functional theory(DFT)calculations completely describe reaction network of ethane dehydrogenation.Onlattice kinetic Monte Carlo simulations were carried out to evaluate catalytic performance under the realistic conditions.The Co/g-C_(3)N_(4),Rh/g-C_(3)N_(4),Ni/g-C_(3)N_(4)catalysts were screened out to exhibit higher C_(2)H_(4)(g)formation activity and C_(2)H_(4)(g)selectivity close to or equal to 100%.The low reactant partial pressure 0%–5%at atmospheric pressure facilitates ethane dehydrogenation,and the appropriate temperatures over Co/g-C_(3)N_(4),Rh/g-C_(3)N_(4),Ni/g-C_(3)N_(4)catalysts are 673.15,723.15,723.15 K,respectively.Especially,Co/g-C_(3)N_(4)catalyst presents the highest C_(2)H_(4)(g)formation activity,attributing to the appropriate antibonding strength between C atom and metal single-atom.Further,a simple descriptor,the reaction energy of C_(2)H_(5)*dehydrogenation to C_(2)H_(4)*,was proposed to quantitatively and quickly evaluate C_(2)H_(4)(g)formation activity.The present study laid a solid foundation for efficient design and development of single-atom catalysts with high-performance for selective dehydrogenation of alkanes.
基金
the National Key R&D Program of China(No.2021YFA1502804)
the National Natural Science Foundation of China(Nos.22078221 and 21776193)
the Science Foundation for Distinguished Young Scholar of Shanxi Province(No.20210302121005).
作者简介
Address correspondence to Baojun Wang,wangbaojun@tyut.edu.cn;Address correspondence to Riguang Zhang,zhangriguang@tyut.edu.cn。
