【摘要】 采用等容法研究了机械球磨工艺制备的Li-Mg-N-H材料储氢性能,结果发现,在室温下采用氦气对样品室体积进行标定时,由于Li-Mg-N-H材料对氦气有一定量的物理吸附,造成准确Li-Mg-N-H材料样品体积标定误差,进而造成Li-Mg-N-H储氢材料在503 K下放氢容量随压力的降低而增加异常变化。为准确标定样品体积,通过对Li-Mg-N-H材料室温氦气吸附容量测定,并采用迭代计算方法获得准确的储氢材料样品体积,进而测定Li-Mg-N-H储氢材料503 K下放氢PCT曲线,其表现为放氢容量随压力降低而减小的正常变化规律。Li-Mg-N-H储氢材料503 K,9.6 MPa氢压下的最大储氢容量为4.81%(质量分数),放氢过程表现为单一放氢平台特性。更多还原

【Abstract】 The hydrogen storage properties of Li-Mg-N-H prepared by mechanical milling were studied by Sieverts technique.It was found that there was error in calibrating the Li-Mg-N-H volume using the helium gas at room temperature due to the physical absorption of helium gas,resulted in abnormal hydrogen desorption PCT curve at 503 K,and the hydrogen storage capacity of Li-Mg-N-H in-creased with decreasing hydrogen pressure.In order to study the hydrogen storage property,the accurate sample’s volume was calculat-ed by iterative algorithm on the base of the physical absorption capacity of helium gas in Li-Mg-N-H.The hydrogen desorption PCT curve for Li-Mg-N-H at 503 K exhibited a normal shape,and the hydrogen storage capacity decreased with decreasing hydrogen pres-sure.The Li-Mg-N-H could reversibly store hydrogen of 4.81%(mass fraction) and the hydrogen desorption PCT curve had a single plateau.更多还原