MgH2-MoS2-PP复合材料的储氢性能

摘要

通过球磨法制备了MgH2-MoS2-PP(PP=热解聚苯胺,wMoS2=wPP=8.33％)复合材料.与纯MgH2对比研究发现,复合材料的初始放氢温度从650 K下降到550 K,并且在573 K下,75 min内的放氢量从0.38％(w/w,下同)提高到2.36％.在423 K下,放氢后产物可在40 min内吸氢2.45％,比纯MgH2高出2.13倍.放氢反应的活化能比纯MgH2(101.83 kJ·mol-1)降低了28.81 kJ· mol-1.MgH2-MoS2-PP复合材料的性能提高是由于PP能够均匀地减小Mg颗粒尺寸,并提高MoS2在体系放氢与再吸氢过程中的催化效率.%A composite of MgH2-MoS2-PP (PP=pyrolyzed polyaniline,wMoS2=wPP=8.33％) was prepared by ballmilling.In comparison to pure MgH2,the onset decomposition temperature of the composite decreases from 650 to 550 K and the hydrogen desorption content increases from 0.38％ to 2.36％ (w/w,the same below) at 573 K within 75 min.The composite can absorb 2.45％H2 within 40 min,which is 2.13 times higher than that of the MgH2 at 423 K.The apparent activation energy of the composite is 101.83 kJ ·mol-1,decreasing by 28.81 kJ ·mol-1 compared to MgH2.The reason of superior hydrogen storage performance of the PP-MoS2-MgH2 composite is found to be that PP can effectively decrease the size of Mg particles and enhance the catalytic efficiency of MoS2 in the desorption-resorption cycling.