金属催化剂对储氢材料(90-x)Mg5C5NCxM(M=Al,Mo或Ni,x=0～10)性能的影响

The Effect of Metal Catalysts on Properties of Hydrogen Storage Materials(90-x)Mg5C5NCxM(M=Al,Mo or Ni,x=0～10)

添加金属催化剂是改善镁基储氢材料储氢性能的有效方式。为研究金属Al,Mo,Ni对镁碳材料的储氢性能的催化作用,用氢气反应球磨法制备了镁碳储氢材料(90-x)Mg5C5NCxM(C=无烟煤基微晶碳,NC=针状焦,M=Al,Mo或Ni,x=0～10),并用排水法放氢测试装置和差示扫描量热分析仪对材料的放氢性能进行了测试。结果表明,添加适量的金属催化剂均能够提高材料的储氢密度,其中添加0.5%的Al可使储氢密度提高11.9%,达4.7%,但Al添加量≥2%时,物料在球磨时容易发生焊接,导致储氢密度降低;Ni具有催化储氢材料放氢的作用,材料89Mg5C5NC1Ni的初始放氢温度仅206.4℃,比不添加Ni时降低了119.2℃。

Adding metal catalysts to Mg-based hydrogen storage materials was an effective way to improve the hydrogen storage properties.To study the catalyses of Al,Mo and Ni so as to improve the hydrogen storage properties of Mg/C materials,the Mg/C hydrogen storage materials（90-x） Mg5C5NCxM（C = anthracite-based crystallitic carbon,NC = needle coke,M = Al,Mo,or Ni,x=0~10） were prepared by reactive ball milling method under hydrogen atmosphere.Then,dehydrogenation properties of materials were tested by the dehydrogenation testing apparatus with dewatering method and differential scanning calorimeter.The results showed that adding suitable metal catalysts could increase the hydrogen capacity of Mg/C hydrogen storage materials.Among them,adding 0.5% of Al could increase the hydrogen capacity of the material by 11.9%,achieving 4.7% in comparation with the material without any metal catalysts.But,when the Al content was more than 2%,the material was easy to conglutinate during the milling process,which decreased the hydrogen capacity.It was also found that Ni was an effective catalyst on the dehydrogenation of the materials.The initial dehydrogenation temperature of 89Mg5C5NC1Ni was 206.4 ℃,119.2 ℃ lower than that of the material without Ni.