镁基储氢复合材料放氢过程相转变速率研究

phase transformation rate study of Mg-based hydrogen storage material during desorption

用机械合金化方法 ,在充氢球磨条件下 ,经不同时间球磨 ,制备Mg Ni MnO2 储氢材料。用自行研制的储氢性能测试装置对这种材料放氢过程中的相转变速率进行了测试 ,并与经相同的球磨工艺制备的Mg Ni、Mg MnO2 储氢材料的储氢性能进行了比较。试验结果表明 :球磨时间对Mg Ni MnO2 储氢材料的粒度有影响 ;颗粒大小对放氢过程的相转变速率有影响。颗粒越小 ,相转变速率的相对峰值越大 ,完成相变所用的时间相对要短 ;Ni与MnO2 同时催化的镁基储氢材料放氢性能明显高于Ni或MnO2 单独催化的储氢材料。

Through mechanical alloying, the Mg-Ni-MnO2 hydrogen storage material was prepared under hydrogen atmosphere, and the hydrogen storage properties measuring apparatus designed by ourselves is used to study the phase transformation velocity of this material during desorption; and the comparison of the dehydriding properties was made between Mg-Ni-MnO2 and Mg-Ni, Mg-MnO2 hydrogen storage material prepared by the same milling process. The result shows that: milling time has effect on the particle size of Mg-Ni-MnO2 hydrogen storage material; the longer the milling time, the less the particle size. The particle size has effect on the phase transformation rate during desorption; the less the particle size, the bigger the relative peak value of phase transformation rate is, and the time of finishing phase transformation become shorter relatively. The dehydriding properties of Mg-based hydrogen storage material catalyzed by Ni and MnO2 together is more excellent markedly than that catalyzed by Ni or MnO2 respectively.