微晶碳在镁基复合储氢材料中的作用

为了提高金属镁的放氢动力学性能，将无烟煤经脱灰并碳化后制得的微晶碳添加到镁粉中，用氢气反应球磨法一步制得高性能镁碳复合储氢材料。用X射线衍射和红外光谱对微晶碳的结构进行了表征，用透射电镜、引射线能谱、粉末X射线衍射对储氢材料的结构进行了测试，用差示扫描量热分析和P—C-T分析对材料的储氢性能进行了研究。结果表明，微晶碳具有类石墨晶体结构，对镁有良好的助磨作用，并与镁有协同吸氢和放氢作用。镁粉中添加40％微晶碳，球磨2h的粒度即可达到30-50nm，储氢材料的初始放氢温度可低至227.4℃，储氢密度可达6.7％。

The Effect of Microlitic Carbon in Mg-based Composite Hydrogen-stored Materials

In order to improve the hydrogen release dynamic performance of metal magnesium, the microlitic carbon prepared from anthracite by demineralization and carbonization was used to add into the magnesium powders to produce the magnesium carbon composed hydrogen stored materials with high performance by reactive ball milling method under hydrogen atmosphere. The structure of microlitic carbon was characterized by the X ray diffraction and infrared spectrum, and that of the hydrogen stored material was tested by the transmission electron microscope, X-ray energy spectrum, and powder X-ray diffraction. The performance of hydrogen storage for materials was investigated by differential scanning calorimetry and p-c-T test. The results show that the microlitic carbon is of similar structure to graphite, the cart,on acts as milling aid for magnesium powder during ball milling, and the synergistic effect for hydrogenation and dehydrogenation occurs between magnesium and microlitic carbon. With the addition of 40% of microlitic carbon, the magnesium particles are milled to 30-50 nm in 2 h and the initial dehydrogenation temperature of the resulted hydrogen stored material decreases to 227.4℃ as well as the hydrogen stored density is up to 6.7%.