Non-stoichiometric Ni_(3)ZnC_(0.7)carbide loading on melamine sponge-derived carbon for hydrogen storage performance improvement of MgH_(2)  

作　　者：Zi-Yin Dai Ping Wu Li-Rong Xiao Hideo Kimura Chuan-Xin Hou Xue-Qin Sun Si-Jie Guo Wei Du Xiu-Bo Xie 

机构地区：[1]School of Environmental and Material Engineering,Yantai University,Yantai,264005,China [2]University of Tennessee Knoxville,Knoxville,TN,37996,USA [3]Shandong University of Aeronautics,Binzhou,256603,China

出　　处：《Rare Metals》2025年第1期515-530,共16页稀有金属(英文版)

基　　金：supported by the National Natural Science Foundation of China(No.52101274);the Natural Science Foundation of Shandong Province(Nos.ZR2020QE011 and ZR2022ME089);Youth Top Talent Foundation of Yantai University(No.2219008);Graduate Innovation Foundation of Yantai University(No.GIFYTU2240);College Student Innovation and Entrepreneurship Training Program Project(No.202311066088).

摘　　要：The high operating temperatures and slow kinetics limit the application of MgH_(2)-based hydrogen storage materials.Here,a composite of Ni_(3)ZnC_(0.7)/carbon nanotubes loaded onto a melamine sponge-derived carbon(MS)skeleton is prepared and loaded onto MgH_(2).During dehydrogenation,Ni_(3)ZnC_(0.7)reacts with MgH_(2)and in situ changes to Mg_(2)Ni/Zn.The transformation of Mg_(2)Ni/Mg_(2)NiH_(4) serves as a“hydrogen pump”,providing diffusion channels for hydrogen atoms and molecules to promote the de-/hydrogenation processes.Moreover,Zn/MgZn_(2) provides the catalytic sites for the transformation of Mg/MgH_(2).The length of the Mg-H bond is elongated from 1.72 to 1.995Å,and the dissociation energy barrier of MgH_(2)is reduced from 1.55 to 0.49 eV.As a result,MgH_(2)with 2.5 wt%MS@Ni_(3)ZnC_(0.7)can absorb 5.18 wt%H_(2)at 423 K within 200 s,and its initial dehydrogenation temperature is reduced to 585 K.After 20 cycles,the dehydrogenation capacity retention is determined to be 94.6%.This work demonstrates an efficient non-stoichiometric metal carbide catalyst for MgH_(2).

关 键 词：Mg-based hydrogen storage materials Non-stoichiometric carbide Ni_(3)ZnC_(0.7) Multiple catalysts Hydrogen storage kinetics 

分 类 号：TG1[金属学及工艺—金属学]