Magnesium-based hydrides have been widely recognized as an appropriate choice for solid-state hydrogen storage.However,its undesirable thermodynamics and sluggish hydrogenation/dehydrogenation kinetics are major bottl...Magnesium-based hydrides have been widely recognized as an appropriate choice for solid-state hydrogen storage.However,its undesirable thermodynamics and sluggish hydrogenation/dehydrogenation kinetics are major bottlenecks for its application.Herein,a highly stable and highly dispersed Ni-based catalyst(Ni/Al_(2)O_(3)/GN)was fabricated to promote the hydrogen storage performance of MgH_(2)via the electrostatic effect of NiAl-LDH/GN precursor with a co-calcination reduction process.MgH_(2)-5wt%Ni/Al_(2)O_(3)/GN exhibits excellent hydrogen storage performance,releasing about 5.7 wt%hydrogen in 3500 s at 250℃,and can reach a saturation hydrogen absorption of about 6.15 wt%in 3000 s at 100℃.Furthermore,it also shows low dehydrogenation apparent activation energy of 89.1 and 118.2 kJ·mol^(-1).Impressively,the catalyst ensures the stability of both the physical phase and structure during ball milling and cycling process.The role of each phase in Ni/Al_(2)O_(3)/GN on the hydrogen storage performance of MgH_(2)was also discussed through experiments and theoretical calculation,and the synergistic catalytic mechanism of Ni/Al_(2)O_(3)/GN was clearly elaborated.This work provides a unique perspective for the preparation of highly stable and highly dispersible catalysts.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.52071177,52171214 and U2330111)the Postgraduate Research Practice Innovation Program of Jiangsu Province(No.KYCX22-1289)+2 种基金China Postdoctoral Science Foundation(No.2023M731637)Jiangsu Funding Program for Excellent Postdoctoral Talent(No.2023ZB102)the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions。
文摘Magnesium-based hydrides have been widely recognized as an appropriate choice for solid-state hydrogen storage.However,its undesirable thermodynamics and sluggish hydrogenation/dehydrogenation kinetics are major bottlenecks for its application.Herein,a highly stable and highly dispersed Ni-based catalyst(Ni/Al_(2)O_(3)/GN)was fabricated to promote the hydrogen storage performance of MgH_(2)via the electrostatic effect of NiAl-LDH/GN precursor with a co-calcination reduction process.MgH_(2)-5wt%Ni/Al_(2)O_(3)/GN exhibits excellent hydrogen storage performance,releasing about 5.7 wt%hydrogen in 3500 s at 250℃,and can reach a saturation hydrogen absorption of about 6.15 wt%in 3000 s at 100℃.Furthermore,it also shows low dehydrogenation apparent activation energy of 89.1 and 118.2 kJ·mol^(-1).Impressively,the catalyst ensures the stability of both the physical phase and structure during ball milling and cycling process.The role of each phase in Ni/Al_(2)O_(3)/GN on the hydrogen storage performance of MgH_(2)was also discussed through experiments and theoretical calculation,and the synergistic catalytic mechanism of Ni/Al_(2)O_(3)/GN was clearly elaborated.This work provides a unique perspective for the preparation of highly stable and highly dispersible catalysts.
