脱氢
氢气储存
煅烧
催化作用
氢
动力学
化学工程
价(化学)
化学
材料科学
无机化学
有机化学
量子力学
物理
工程类
作者
Xuelian Zhang,Ke Wang,Xin Zhang,Jianjiang Hu,Mingxia Gao,Hongge Pan,Yongfeng Liu
摘要
High operation temperatures and slow reaction kinetics are major obstacles to use MgH2 as a solid hydrogen store. We report here the synthesis of Nb2O5 hollow spheres (o-Nb2O5) with wall thickness of approximately 50 nm and mossy surfaces using a facile hydrothermal and calcination process, which showed high activity in catalysis of MgH2 for hydrogen storage. The dehydrogenation onset temperature of MgH2 was decreased to 195°C with 7 wt% of o-Nb2O5. More than 5.5 wt% H2 can be desorbed at 300°C within 5 minutes. Hydrogen re-absorption starts even at 25°C and reaches 5.6 wt% within 5 minutes at 200°C. Practical hydrogen capacity stabilizes at 5.8 wt% after 10 cycles of hydrogen uptake/release. The o-Nb2O5 was found to be reduced in situ by MgH2 to low-valence Nb species during the initial dehydrogenation process, which functions as an active catalyst and leads to the enhanced dehydrogenation kinetics.
科研通智能强力驱动
Strongly Powered by AbleSci AI