摘要
Mn nanoparticles(nano-Mn)were successfully synthesized and doped into MgH_(2) to improve its de/hydrogenation properties.Compared with MgH_(2),the onset desorption temperature of 10 wt.%nano-Mn modified MgH_(2) was decreased to 175℃ and 6.7,6.5 and 6.1 wt.%hydrogen could be released within 5,10 and 25 min at 300,275 and 250℃,respectively.Besides,the composite started to take up hydrogen at room temperature and absorbed 2.0 wt.%hydrogen within 30 min at low temperature of 50℃.The hydrogenation activation energy of MgH_(2) was reduced from(72.5±2.7)to(18.8±0.2)kJ/mol after doping with 10 wt.%nano-Mn.In addition,the MgH_(2)+10 wt.%nano-Mn composite exhibited superior cyclic property,maintaining 92%initial capacity after 20 cycles.
合成锰纳米颗粒并掺杂到MgH_(2)中以改善其吸放氢性能。与MgH_(2)相比,含10%(质量分数)锰纳米颗粒的MgH_(2)其初始放氢温度下降到175℃。在300、275和250℃下,该复合体系能在5、10和25 min之内分别释放出6.7%、6.5%和6.1%(质量分数)的氢气。此外,该复合体系在室温下即可吸氢,并能在50℃、30 min之内吸收2.0%(质量分数)的氢气。在掺杂10%(质量分数)锰纳米颗粒后,MgH_(2)吸氢反应的活化能从(72.5±2.7) kJ/mol降低到(18.8±0.2) kJ/mol,该复合体系表现出优异的循环性能,在20次循环后保持着92%的初始容量。
基金
financial supports from the National Natural Science Foundation of China (No. 51801078)
the Natural Science Foundation of Jiangsu Province, China (No. BK20180986)。
