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采用球磨的方式在NaAlH4中掺入稀土催化剂Ce(SO4)2,通过X射线衍射仪(XRD)、扫描电镜(SEM)及PCT(pressure content tempera-ture)测试仪研究了球磨时间对NaAlH4的相结构和吸放氢性能的影响。结果表明,经过不同时间球磨后,掺杂Ce(SO4)2的NaAlH4样品仍由NaAlH4相和Ce(SO4)2相组成,球磨没有改变样品的相组成。但是样品的放氢温度均降低,并在球磨6 h时达到最大程度,放氢温度下降了40℃。吸氢后的样品中均存在Al,Na3 AlH6和掺杂相Ce(SO4)2,球磨3和6 h的样品还存在NaAlH4相,说明第二步吸氢反应的程度较大。球磨6 h的样品的吸氢性能最好,吸氢量达到3.598%(质量分数)。球磨时间越长,颗粒越细小,颗粒细化是提高样品吸放氢性能的主要原因。但球磨时间过长后,颗粒团聚逐渐严重,吸放氢性能下降。
The rare earth catalyst Ce (SO4) 2 was doped into NaAlH4 by ball milling. The effect of ball milling time on the phase of NaAlH4 Structure and Hydrogen Absorption and Desorption Properties. The results show that NaAlH4 doped with Ce (SO4) 2 is still composed of NaAlH4 phase and Ce (SO4) 2 phase after ball milling at different time. The ball milling does not change the phase composition of the sample. However, the dehydrogenation temperature of the samples decreased and reached the maximum level after milling for 6 h, and the desorption temperature decreased by 40 ℃. After hydrogen absorption, Al, Na3AlH6 and doped phase Ce (SO4) 2 were all present in the samples. The NaAlH4 phase was also observed in the samples after milling for 3 and 6 h, which indicated that the second step was more hydrogen absorption. The samples with ball milling for 6 h had the best hydrogen absorption capacity and the hydrogen absorption reached 3.598% (mass fraction). The longer milling time, the finer the particles and the finer particles are the main reasons to improve the hydrogen absorption and desorption performance. However, after milling time is too long, the particle agglomeration gradually serious, hydrogen absorption and desorption performance.