摘要
利用密度泛函理论(DFT),基于7T簇模型,在B3LYP/6-31G(d,p)水平上研究了NO分子在H-ZSM-5分子筛孔道中α,β,γ酸性位的吸附.在计算过程中,首先对H-ZSM-5的α,β,γ酸性位进行优化计算,然后对NO分子η1-N和η1-O两种吸附模式的红外光谱和吸附能进行计算.计算结果表明,NO分子以η1-N模式吸附于H-ZSM-5分子筛酸性位上,不同酸性位对NO分子的吸附能力排序为:α酸性位>β酸性位>γ酸性位.此外,H-ZSM-5分子筛直型孔道更有利于NO分子的吸附和扩散,因而可更有效地促进NO分子催化分解反应的进行.
The adsorption of NO molecule at the α,β and γ Brnsted acid sites of different channels of molecular sieve H-ZSM-5 zeolite was investigated using density functional theory（DFT） at the level of B3LYP/6-31G（d,p）,which was conducted on the basis of 7T clusters.Thus the α,β and γ Brnsted acid sites were optimized,and the infrared spectra and the adsorption energies of NO molecules in η1-N and η1-O adsorption modes were calculated.The calculated results show that NO molecule is adsorbed at the α,β and γ Brnsted acid sites in the form of η1-N mode.The adsorption energies of various acid sites,in terms of the ability to adsorb NO molecule,are ranked as α acid site β acid site γ acid site.Moreover,the straight channels of H-ZSM-5 zeolite possess stronger ability for the adsorption and diffusion of NO molecule,thereby more effectively accelerating the catalytic decomposing reaction of NO molecule.
出处
《化学研究》
CAS
2012年第2期22-25,共4页
Chemical Research
作者简介
唐保卫（1983-），男，硕士，研究方向为工业催化．通讯联系人，E-mail：qhguo@henu．edu．cn．
