期刊信息
- 刊名： 河北师范大学学报（自然科学版）Journal of Hebei Normal University (Natural Science)
- 主办： 河北师范大学
- ISSN： 1000-5854
- CN： 13-1061/N
- 中国科技核心期刊
- 中国期刊方阵入选期刊
- 中国高校优秀科技期刊
- 华北优秀期刊
- 河北省优秀科技期刊
Ti,Nb和Zr掺杂对Ca(BH4)2·2NH3储氢性能的影响
- 河北师范大学 化学与材料科学学院, 河北 石家庄 050024
-
DOI：10.13763/j.cnki.jhebnu.nse.2015.01.008
Influence of Ti,Nb and Zr Dopants on the Hydrogen Storage Properties of Ca(BH4)2·2NH3
摘要/Abstract
基于密度泛函理论的第一性原理,研究了掺杂元素Ti,Nb和Zr取代Ca原子后对Ca(BH4)2·2NH3储氢性能的影响.通过计算体系的晶体结构、占位能、态密度及电子密度拓扑性质,分析了原子间的成键情况和结构稳定性.结果表明:Ti,Nb,Zr分别取代Ca(BH4)2·2NH3中的Ca原子,Ti取代最容易形成稳定结构,Zr次之,Nb最难形成.Ca(BH4)2·2NH3结构中,B—H,N—H键都以共价作用为主,且N—H键比B—H键作用强.掺杂原子取代后改变BH4基团的稳定性,同时掺杂原子对N作用增强,减弱NH3分子释放对脱氢的影响.Nb原子取代对B—H影响最大,最能改善Ca(BH4)2·2NH3体系的脱氢性能,使H更易脱去.
The influences on the hydrogen storage properties of Ti,Nb,Zr substituted Ca atom of Ca(BH4)2·2NH3 are studied by the first principles calculations.The bonding properties and structural stability are discussed based on the geometry,occupation energy,density of electronic states and topological analysis of electron density.The results show that Ti is the easiest while Zr is easier than Nb to replace Ca. In Ca(BH4)2·2NH3,B—H bond and N—H bond are belong to covalent bonds,and B—H bond is weaker than N—H bond.Transition metal elements doping change the stability of BH4.At the same time,the strengthened interaction between dopants and N atom reduce the release of NH3 on hydrogen dissociation.Among the Ti,Nb and Zr,the influence of Nb atom on the B—H bond is the greatest,which improves the dehydrogenation performance of Ca(BH4)2·2NH3,and makes the dissociation of H becomes easier.
关键词
参考文献 16
- [1] MARDER T B.Will We Soon Be Fueling Our Automobiles with Ammonia-borane? [J].Angewandte Chemie,2007,46 (43):8116-8118.
- [2] NAKAMORI Y,MIWA K,NINOMIYA A,et al. Correlation Between Thermodynamical Stabilities of Metal Borohydrides and Cation Electronegativites: First-principles Calculations and Experiments[J].Physical Review B,2006,74(4):045126-045134.
- [3] CHU H,WU G,XIONG Z,et al.Structure and Hydrogen Storage Properties of Calcium Borohydride Diammoniate[J].Chemistry of Materials,2010,22(21):6021-6028.
- [4] RAMZAN M,SILVEARV F,LEBEGUE S,et al.Electronic Structure from First-principles of LiBH4·NH3,Sr-(NH2BH3)2,and Li2Al(BH4)5·6NH3 for Hydrogen Storage Applications[J].Phy Chem C,2011,115(40):20036-20042.
- [5] SOLOVEICHIK G,HER J H,STEPHENS P W,et al.Ammine Magnesium Borohydride Complex as a New Material for Hydrogen Storage:Structure and Properties of Mg(BH4)2·2NH3[J].Inorg Chem,2008,47(10):4290-4298.
- [6] CHEN X,YU X.Electronic Structure and Initial Dehydrogenation Mechanism of M(BH4)2·2NH3(M = Mg,Ca,and Zn):A First-principles Investigation[J].Phy Chem C,2012,116(22):11900-11906.
- [7] KRESSE G.Efficient Iterative Schemes for Ab Initio Total-energy Calculations Using a Plane-wave Basis Set[J].Physical Review B,1996,54(16):11169-11186.
- [8] PERDEW J,BURKE K,WANG Y.Generalized Gradient Approximation for the Exchange-correlation Hole of a Many-electron System[J].Physical Review B,1996,54(23):16533-16539.
- [9] YVON K,SCHEFER J,STUCKI F.Structural Studies of the Hydrogen Storage Material Mg2NiH4 1:Cubic High-temperature Structure[J].Inorganic Chemistry,1981,20(9):2776-2778.
- [10] KRESSE G.From Ultrasoft Pseudopotentials to the Projector Augmented-wave Method[J].Physical Review B,1999,59(3):1758-1775.
- [11] CHADI D.Special Points for Brillouin-zone Integrations[J].Physical Review B,1977,16(4):1746-1747.
- [12] BADER R F W.Atoms in Molecules A Quantum Theory[M].Oxford:Oxford University Press,1990.
- [13] FRISCH M J,TRUCKS G W,SCHLEGEL H B,et al.Gaussian 03,Program[M].Revision D 02.Pittsburgh P A:Gaussian Inc,2004.
- [14] BIEGLER-KONING F J,DERDAU R,BAYLES O,et al.AIM 2000[M].Version 1.0.Bielefeld:University of Applied Science,2000.
- [15] 赵影,曾艳丽,郑世钧,等.卤键的研究进展[J].河北师范大学学报:自然科学版,2007,31(1):93-98.
- [16] 张梅,李晓艳,孟令鹏.1,8-双取代萘衍生物中新型离域键性质的理论研究[J].河北师范大学学报:自然科学版,2014,38(5):497-501.