金属间电子化物纳米颗粒制备及催化性能研究

金属间电子化物具有较小的功函数、独特的可逆氢存储释放能力以及优异的化学稳定性，是一种新型催化剂材料，在加氢热催化、电催化析氢等领域表现出巨大的应用潜力。然而目前大多数金属间电子化物通过电弧熔炼法（arc melting method）或者固相反应路线（solid-state reactions）合成，产物通常为块体材料（尺寸通常大于1 mm），这导致其比表面积过小，限制了其催化性能的发挥。虽有人提出用金属闪蒸法制备金属间电子化物纳米颗粒，但由于高成本、低产量等缺点，较难进行实际应用。

针对以上问题，本课题基于简单的熔盐法，创新性地以CaH2/Ca 作为还原剂、KCl/LiCl-KCl共晶作为熔盐，成功制备了金属间电子化物纳米颗粒。主要研究内容及结果归纳如下：

在氩气保护的非密闭体系下，采用以CaH2为还原剂改进的熔盐法实现了金属间电子化物LaCu0.67Si1.33的纳米化。其平均粒径小于100 nm，比表面积高达44.5 m2 g-1。此外，以Ca为还原剂成功合成出金属间电子化物Y5Si3纳米颗粒，其比表面积同样达到了11.8 m2 g-1。本论文还进一步探究了其它金属间电子化物YB2、LaCoSi的纳米化制备方法。研究结果表明，通过熔盐法制备金属间电子化物纳米颗粒具有普适性，推广了熔盐法的应用范围，为金属间电子化物的纳米化提供了有效途径。

在此基础上，研究了金属间电子化物LaCu0.67Si1.33、Y5Si3的二氧化碳还原、选择加氢以及电催化析氢等催化性质，结果表明其催化性能优异，表现出极大的应用潜力。

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