氢化燃烧合成Mg_2NiH_4的影响因素研究

Research on the Effect Factor of Hydriding Combustion Synthesis of Mg_2NiH_4

研究了气氛压力、燃烧温度和保温时间对合成Mg2NiH4的影响,对产物进行了XRD和SEM分析,结果表明,在镁镍共晶温度附近,于氩气气氛中燃烧合成1h就能生成大量的Mg2Ni,保温2h,反应更为完全。随着氢压的增大,镁镍氢化物有明显的增加,在2.2MPa时,金属镍完全消失。随着合成温度的升高,镁镍氢化物有所增加,但温度太高,不利于Mg2NiH0.3进一步氢化形成Mg2NiH4。适当的保温时间可促进镁镍合成反应的进行。

The effect of hydrogen gas pressure,synthesizing temperature and the temperature holding time on the product of Mg_2NiH_4 is investigated and the product is analyzed by using XRD and SEM. It is manifested that combustion in argon atmosphere for one hour at the temperature near to the eutectic point of magnesium and nickel,plenty Mg_2Ni is formed and the combustion reaction is reaching complete as holding the temperature for two hours.The quantity of magnesium nickel hydride increases evidently with the boosting of hydrogen gas pressure and the nickel tends to become disappeared under the hydrogen gas pressure 2.2MPa.The quantity of magnesium nickel hydride increases with the rising of synthesizing temperature,but overtemperature is not advantageous to the formation of Mg_2NiH_4 from Mg_2NiH_(0.3) and holding the temperature for a proper time is advantageous to the synthesizing reaction of magnesium and nickel.