【摘要】 采用机械合金化方法制备了Mg2Ni纳米材料。不同扫描速度/温度下的循环伏安测试结果表明:样品的氧化峰电位随扫描速度的加快而正移;室温下的吸氢性能显著增强,吸放氢速度随温度的升高而加快。X射线小角散射结果表明:该材料具有1～5nm以及5～10nm的粒度分布,较小的粒度使得吸放氢反应的活性位置增多和放氢的扩散路径减少,这可能是导致材料贮氢性能显著提高的原因。循环寿命的快速检测结果表明:Mg2Ni纳米贮氢合金电极的活性很好;经过200次循环后,其容量保持率为66%。在电极一侧涂覆环氧树脂后其电化学活性未受到明显影响,容量保持率优于未涂覆的电极;但阴极峰和阳极峰电流值显著下降,说明吸放氢反应的速率以及充放电程度有所降低。更多还原

【Abstract】 The nanocrystalline Mg2Ni materials were prepared by mechanical alloying.The cyclic voltammetry results indicated that the potential of oxidation peak was shift as the scan rate increased and the absorption property of Mg2Ni prepared by mechanical alloying was increased even at ambient temperature.The absorption and desorption of hydrogen in Mg2Ni alloy were remarkably accelerated with the rising temperature.Small angel X-ray scattering results indicated that the Mg2Ni powder have 1~5 nm and 5~10 nm particle size distribution,which increased the acting sites of hydrogen absorbtion/desorption reaction and decreased the diffusion path of hydrogen desorption.It was induced to the enhanced performance of Mg2Ni nanocrystalline powder.The cycle life investigated results indicated that the activation property of Mg2Ni nanocrystalline hydrogen storage alloy electrode was execellent,the capacitance maintenance ration was 66% after 200 cycles.The coating of epoxy resin on one side of the electrode had no effect on the activation property and the capacitance maintenance ration was better than the uncoating one.But the anode peak current value and the cathodic peak current value were decreased remarkably which indicated that the hydrogen absorption/desorption rate and the charge/discharge degree had decreased.更多还原