Stable hydrogen storage of lithium borohydrides via the catalytic effect of Ni_(2)B induced by thermodynamic destabilization reaction  

作　　者：Yukun Liu Wei Chen Shunlong Ju Xuebin Yu Guanglin Xia 

机构地区：[1]Department of Materials Science,Fudan University,Shanghai 200433,China

出　　处：《Journal of Materials Science & Technology》2024年第35期192-200,共9页材料科学技术(英文版)

基　　金：supported by the National Key R&D Program of China(No.2021YFB3802400);the National Natural Sci-ence Foundation of China(Nos.22279020,22109026,51971065,51901045,U2130208,and 52071156);the Science and Technology Commission of Shanghai Municipality(Nos.21ZR1407500 and 23ZR1406500).

摘　　要：Lithium borohydride(LiBH_(4))is regarded as a potential hydrogen storage material due to its high gravi-metric and volumetric capacity,but its practical application suffers from high operating temperature and poor reversibility.Herein,porous hollow carbon microspheres composed of carbon-coated Ni nanoparti-cles with high content(denoted as Ni/C)are rationally designed as functional support,which not only induces effective nanoconfinement of LiBH4 but also promotes efficiently homogeneous destabilization reaction between LiBH4 and Ni nanoparticles.The introduction of Ni nanoparticles leads to the decrease of the Gibbs free energy change for H_(2)desorption of LiBH4 based on the formation of Ni_(2)B down to−0.95 eV while this value reaches 1.19 eV for bulk LiBH4,validating the effective role of Ni in thermo-dynamically destabilizing H_(2)desorption.Impressively,the average B-H bond length of LiBH4 on Ni_(2)B reaches 1.291A and thus the corresponding dissociation energy of removing one H atom from LiBH4 is lowered to 1.00 eV,much lower than bulk LiBH4(4.22 eV)and even LiBH4 on Ni(1.27 eV),which verifies superior role of Ni_(2)B than Ni in catalytically enhancing H_(2)desorption.Therefore,a capacity of 8.86 wt.%is obtained for LiBH4 confined into Ni/C at 320℃ after 10 cycles.

关 键 词：Hydrogen storage Lithium borohydride Thermodynamic destabilization reaction Catalytic effect REVERSIBILITY 

分 类 号：TB3[一般工业技术—材料科学与工程]