LaCl3和Ti对氢化铝钠（NaAlH4）和氢化铝锂（LiAlH4）储氢性能的影响

通过PCT(pressure-content-temperature)设备研究催化剂Ti和 LaCl3对NaAlH4和LiAlH4储氢性能的影响.NaAlH4和LiAlH4掺杂LaCl3比掺杂Ti的放氢性能有明显提高.在吸氢性能的研究中发现,在第1个吸氢循环中,掺杂3 mol% LaCl3的NaAlH4试样的放氢温度明显降低.此外,LaCl3的摩尔含量对NaAlH4的放氢性能的影响是非常明显的.研究结果显示,随着LaCl3含量的增加,NaAlH4的放氢量和放氢速率显示出相同的变化趋势,即先增加后减少.其中掺杂3 mol% LaCl3的NaAlH4试样的放氢量最大并且放氢动力学性能最好,其激活能为41.6 kJ/mol,这个值低于所报道的掺杂Ti的NaAlH4的激活能.

Effect of LaCl3 and Ti on Hydrogen Storage Properties of NaAlH4 and LiAlH4

The effects of additives Ti and LaCl3 on the hydrogen storage properties of NaAlH4 and LiAlH4 were investigated by the PCT (pressure-content-temperature) apparatus. NaAlH4 doped with LaCl3 and LiAlH4 doped with LaCl3 both show better capability of hydrogen release than the samples doped with Ti. The study on the first rehydrogenation cycle of NaAlH4 doped with 3 mol% LaCl3 finds that the dehydrogenation temperature has a marked decrease. In addition, the effect of LaCl3 content on hydrogen release of NaAlH4 is very obvious. The result indicates that the amount and rate of hydrogen release show the same change trends, increasing firstly and then decreasing with increasing of LaCl3 content. The sample doped with 3 mol% LaCl3 presents the best dehydrogenation properties in both the amount of hydrogen release and the desorption kinetics. The activation energy of the NaAlH4 sample doped with 3 mol% LaCl3 was measured to be 41.6 kJ/mol. This value is lower than that reported for the Ti-doped NaAlH4.