LiAlH4/LiNH2+Ti/TiF3复合物的储氢性能

Hydrogen Storage Properties of Ti/TiF3-Doping LiAlH4/LiNH2 Composites

摘要:

为改善LiAlH4和LiNH2的储氢性能，将两者混合球磨制备LiAlH4/LiNH2复合体系，并添加TiF3和Ti作为复合体系催化剂。采用DSC、TG、XRD和储氢特性测定等手段研究催化剂TiF3和Ti对LiAlH4/LiNH2复合体系储氢性能的影响。结果表明：添加Ti和TiF3可显著改善Li-Al-N-H储氢体系的放氢动力学性能、提高放氢总量和降低体系的放氢温度。添加5%（摩尔分数，下同）TiF3催化剂后，LiAlH4/LiNH2复合体系球磨过程放氢量由1.27%（质量分数，下同）增加到1.69%，总放氢量由5.95%增加到6.85%。起始放氢温度由150 ℃降低到75 ℃。

Abstract:

In order to improve the hydrogen storage properties of LiAlH4 and LiNH2, LiAlH4/LiNH2 composite was prepared by ball milling the mixture of LiAlH4 and LiNH2 with Ti or TiF3 as catalyst. The effects of Ti and TiF3 catalyst on the hydrogen storage properties of LiAlH4/LiNH2 composite were studied by thermogravimetry (TG), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) and hydrogen storage properties measurements. The results show that Ti or TiF3 addition significantly improves the desorption kinetics, increases the hydrogen desorption capacity, and decreases the initial hydrogen desorption temperature. For the LiAlH4/LiNH2 composite with addition of 5 mol% TiF3, the hydrogen desorption capacity of the composite increaseses from 1.27 wt% to 1.69 wt% during ball-milling process, the total hydrogen desorption capacity increases from 5.95 wt% to 6.85 wt%, and the initial hydrogen desorption temperature decreases from 150 to 75 oC.