(北京有色金属研究总院 能源材料与技术研究所,北京 100088)
摘 要: 采用机械球磨方法在NaAlH4 络合氢化物中添加3%(摩尔分数)TiZr合金氢化物,合成复合储氢材料。采用XRD、SEM和等容法储放氢性能测试等技术对该复合储氢材料的形态、物相和可逆储放氢性能进行研究。结果表明:加入TiZr合金氢化物的NaAlH4 可以实现可逆吸放氢,同时具有良好的储放氢动力学性能,在160 ℃、0.1 MPa放氢条件下,其总放氢量达4.5%(质量分数),40 min可逆放氢量超过3.0 %,且具有良好的循环稳定性; NaAlH4 基体中均匀弥散分布的TiZr合金氢化物,在复合储氢材料吸放氢前后保持物相和结构不变,对NaAlH4 络合氢化物的可逆储放氢反应起到催化改善作用。
关键字: NaAlH4;储氢材料;络合氢化物;TiZr合金氢化物
(Research Center of Energy Material and Technology, General Research Institute for Non-ferrous Metals,Beijing 100088, China)
Abstract:The hydrogen storage properties of NaAlH4 doped by 3%(mole fraction) TiZr alloy hydride with ball-milling method was investigated by X-ray diffractometry, scanning electron microscopy and sievert’s technology test. The results show that the TiZr alloy hydride/NaAlH4 composite has good reversible hydrogen storage properties. The hydrogenation and dehydrogenation kinetics of NaAlH4 can be greatly improved by doping TiZr alloy hydride. The reversible dehydrogenation capacity of this composite reaches to 3.0%(mass fraction) in 40 min and 4.5% in 11 h. The TiZr alloy hydride uniformly distributing in the NaAlH4 substrate has stable phase structure during the hydrogenation/ dehydrogenation cycle, indicating that the catalytic effect of TiZr alloy hydride is the main mechanism for improving the reversible hydrogen storage properties of NaAlH4.
Key words: NaAlH4; hydrogen storage material; complex hydrides; TiZr alloy hydride