中文摘要：

采用机械球磨（NaH/Al＋Ti）和（NaH/Al＋Ti-Zr）复合物的方法加氢制备了NaAlH4配位氢化物,系统研究了Ti、Ti-Zr催化剂以及不同加氢条件对其可逆储氢行为的影响.结果表明,对于NaH/Al体系的吸放氢性能,共掺金属Ti粉/Zr粉的催化作用比单独掺金属Ti粉的催化作用要好.随着加氢温度从85℃上升到140℃,体系的吸氢容量先增后减,并在120℃时达到最大值;同时,发现共掺Ti-Zr催化剂的复合物具有最佳的储氢性能,在120和85℃时的吸氢量分别为4.61%和3.52%（w）,比仅掺Ti催化剂的复合物分别高出0.40%和0.70%（w）的吸氢量.随着加氢压力的增大,（NaH/Al＋Ti-Zr）复合物的吸氢性能随之提高.XRD和DSC分析结果表明,NaAlH4体系的放氢过程明显发生两步分解反应,共掺Ti-Zr催化剂的复合物储氢性能优于单独掺Ti催化剂的原因是,共掺催化剂能有效改善NaAlH4体系吸放氢反应的动力学性能,并降低体系的放氢温度.

英文摘要：

The NaAlH4 complex hydride was prepared by hydrogenation of the ball-milled （NaH/Al＋Ti） and （Nail/ Al＋Ti-Zr） composites. The influences of Ti and Ti-Zr catalysts, different hydriding temperatures and pressures on its reversible hydrogen storage behaviors were investigated. It was found that the catalysis of Ti-Zr powders as cocatalysts on the dehydriding/hydriding characteristics of Nail/Al was better than that of Ti alone as catalyst. As the hydriding temperature increased from 85 ℃ to 140 ℃, the hydrogen absorption capacity increased first and then decreased, and reached the highest value at 120℃. The composite co-doped with Ti-Zr catalysts had the best reversible hydrogen storage properties, its hydrogen storage capacities were 4.61%（w） at 120 ℃and 3.52%（w） at 85 ℃, which were 0.40% and 0.70% （w） higher than that doped with Ti alone as catalyst in the same hydriding condition, respectively. The hydrogen storage performance of （NaH/Al＋Ti-Zr） composite was enhanced with the increase of hydriding pressure. XRD and DSC analyses showed that the dehydriding process of NaAlH4 system took place in two steps. The composite co-doped with Ti-Zr catalysts could improve the dehydriding/hydriding kinetics of NaAlH4 system and reduced its dehydriding temperature. That was the main reason of the hydrogen storage characteristic of the composites co-doped with Ti-Zr catalysts better than that doped with Ti catalyst alone.