NaH doped TiO_(2)as a high-performance catalyst for Mg/MgH_(2)cycling stability and room temperature absorption

作     者：Joshua Adedeji Bolarin Zhao Zhang Hujun Cao Zhi Li Teng He Ping Chen Joshua Adedeji Bolarin;Zhao Zhang;Hujun Cao;Zhi Li;Teng He;Ping Chen

作者机构：Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalianP.R.China University of Chinese Academy of SciencesBeijing 100049P.R.China Shangdong Energy Group Co.LTD.No.10777Jingshi RoadJinan CityShandong Province250014P.R.China School of Material Science and EngineeringXi'an Jiaotong UniversityXi'anShaanxi Province710049P.R.China 

出 版 物：《Journal of Magnesium and Alloys》 (镁合金学报（英文）)

年 卷 期：2023年第11卷第8期

页      面：2740-2749页

核心收录：

学科分类：081705[工学-工业催化] 08[工学] 0817[工学-化学工程与技术] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：The authors acknowledge the Project supported by the National Key R&D Program of China(2019YFE0103600,2018YFB1502101) the Key R&D Program of Shandong Province,China(2020CXGC010402) the National Natural Science Foundation of China(51801197) the Liaoning Revitalization Talents Program(XLYC2002076) the Dalian High-level Talents Program(2019RD09) the Youth Innovation Promotion Association CAS(2019189) K.C.Wong Education Foundation(GJTD-2018–06) 

主　　题：Magnesium hydride NaH doped nanocrystalline TiO_(2) Kinetics Room temperature absorption Reversibility 

摘      要：This paper presents the catalytic effect of NaH doped nanocrystalline TiO_(2)(designated as NaTiOxH)in the improvement of MgH_(2)hydrogen storage *** catalyst preparation involves ball milling NaH with TiO_(2)for 3 *** addition of 5 wt%NaTiOxH powder into MgH_(2)reduces its operating temperature to∼185℃,which is∼110℃lower than the additive-free as-milled MgH_(2).The composite remarkably desorbs∼7.2 wt%H_(2)within 15 min at∼290℃and reabsorbs∼4.5 wt%H_(2)in 45 min at room temperature under 50 bar H_(2).MgH_(2)dehydrogenation is activated at 57 kJ/mol by the *** importantly,the addition of 2.5 wt%NaTiOxH catalyst aids MgH_(2)to reversibly produce∼6.1 wt%H_(2)upon 100 cycles within 475 hr at 300℃.Microstructural investigation into the catalyzed MgH_(2)composite reveals a firm contact existing between NaTiOxH and MgH_(2)***,the NaTiOxH catalyst consists of catalytically active Ti_(3)O_(5),and“rod-likeNa_(2)Ti_(3)O_(7)species liberated in-situ during preparation;these active species could provide multiple hydrogen diffusion pathways for an improved MgH_(2)sorption ***,the elemental characterization identifies the reduced valence states of titanium(Ti4+)which show some sort of reversibility consistent with H_(2)insertion and *** phenomenon is believed to enhance the mobility of Mg/MgH_(2)electrons by the creation and elimination of oxygen vacancies in the defective(TiO_(2-x))*** findings have therefore moved MgH_(2)closer to practical applications.