Exceptional catalytic effect of novel rGO-supported Ni-Nb nanocomposite on the hydrogen storage properties of MgH_(2)

作     者：Samuel Guemou Liuting Zhang Shuai Li Yiqun Jiang Tao Zhong Zichuan Lu Ren Zhou Fuying Wu Qian Li Samuel Guemou;Liuting Zhang;Shuai Li;Yiqun Jiang;Tao Zhong;Zichuan Lu;Ren Zhou;Fuying Wu;Qian Li

作者机构：School of Energy and PowerInstrumental Analysis CenterJiangsu University of Science and TechnologyZhenjiang 212003China National Engineering Research Center for Magnesium Alloys&National Key Laboratory of Advanced Casting Technologies&College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Chongqing Institute of New Energy Storage Materials and EquipmentChongqing 401135China Max Planck Institute for Iron ResearchDüsseldorf 40237Germany 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2024年第172卷第5期

页      面：83-93页

核心收录：

学科分类：081702[工学-化学工艺] 08[工学] 0817[工学-化学工程与技术] 

基　　金：the financial support from the National Natural Science Foundation of China(Grant No.51801078) 

主　　题：Hydrogen storage materials Magnesium hydride Ni-Nb/rGO Kinetic analysis Catalytic mechanism 

摘      要：The design of an excellent active catalyst to improve the sluggish kinetic and thermodynamic properties of magnesium hydride(MgH_(2))remains a great challenge to achieve its practical *** this study,a novel Ni-Nb/rGO nanocomposite catalyst was successfully prepared by one-spot hydrothermal and sub-sequent calcination *** novel Ni-Nb/rGO nanocomposite exhibits an exceptional catalytic effect on improving MgH_(2) sorption ***,the onset desorption temperature of MgH_(2)+10 wt%Ni-Nb/rGO composite is reduced to 198℃,much lower than that of undoped MgH_(2)(330℃).In-terestingly,the composite can release 5.0,5.9,and 6.0 wt%H_(2) within 10 min at 245,260,and 275℃,***,the dehydrogenated MgH_(2)+10 wt%Ni-Nb/rGO composite starts to absorb hydrogen even at room temperature with approximate 2.75 wt%H_(2) uptake at 75℃under 3 MPa H_(2) pressure within 30 min and exhibits excellent stability by maintaining 6.0 wt%hydrogen content after 20 cycles at 300℃.Chou’s model suggests that the de/hydrogenation kinetics of Ni-Nb/rGO-modified MgH_(2) switches from surface penetration model to diffusion model at lower ***,the ac-tivation energies(E a)for the de/hydrogenation of MgH_(2)+10 wt%Ni-Nb/rGO are reduced to 57.8 kJ/mol and 33.9 kJ/mol,which are significantly lower than those of undoped MgH_(2).The work demonstrates that the addition of a novel ternary Ni-Nb/rGO catalyst is an effective strategy to not only boost the sorption kinetics of MgH_(2) but also maintain its cycling property.