Abstract We introduce a facile chemical solid state method to in situ grow MgH2 nanoparticles in various carbon materials. Commercial carbon materials, containing coconut shell charcoal (CSC), multi-walled carbon nanotube (CNT), graphite (G) and activated carbon (AC) are employed as the templates. The MgH2@X (X = CSC, CNT, G and AC) composites were successfully obtained by the simple solid state method. The hydrogen storage properties of MgH2@X (X = CSC, CNT, G and AC) composites are systematically studied by temperature-programmed desorption system, isothermal de/hydrogenation apparatus and differential scanning calorimetry measurements. Experimental results reveal that the MgH2@CSC composites have the most fascinating hydrogen absorption and desorption performance, followed by MgH2@CNT, MgH2@G and MgH2@AC composites. The dehydrogenation of MgH2@CSC composites begins at 245 °C. Moreover, the MgH2@CSC composites exhibit superior de/hydrogenation kinetic performance. The composites could desorb 5.4 wt% hydrogen within 10 min at 325 °C, and the dehydrogenated composites take up 5.0 wt% hydrogen within 5 min at 250 °C under 2 MPa H2 pressure. Among the carbon materials, CSC with layered structure composed of interconnected wrinkles is most beneficial to maintain the high dispersity and nano size of MgH2 nanoparticles, resulting in the superior de/hydrogenation performance.

中文翻译：

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限制在不同碳材料中用于储氢的小型 MgH2 纳米粒子的简便合成

摘要 我们介绍了一种简便的化学固态方法，可以在各种碳材料中原位生长 MgH2 纳米颗粒。包含椰壳炭（CSC）、多壁碳纳米管（CNT）、石墨（G）和活性炭（AC）的商业碳材料被用作模板。MgH2@X（X = CSC、CNT、G 和 AC）复合材料通过简单的固态方法成功获得。MgH2@X（X = CSC、CNT、G和AC）复合材料的储氢性能通过程序升温脱附系统、等温脱氢装置和差示扫描量热法测量进行系统研究。实验结果表明，MgH2@CSC 复合材料具有最迷人的吸氢和解吸性能，其次是 MgH2@CNT、MgH2@G 和 MgH2@AC 复合材料。MgH2@CSC 复合材料的脱氢开始于 245 °C。此外，MgH2@CSC 复合材料表现出优异的脱/氢化动力学性能。该复合材料在 325°C 下可以在 10 分钟内解吸 5.4 wt% 的氢气，在 2 MPa H2 压力下，在 250°C 下，脱氢复合材料在 5 分钟内吸收了 5.0 wt% 的氢气。在碳材料中，由相互连接的皱纹组成的层状结构的CSC最有利于保持MgH2纳米颗粒的高分散性和纳米尺寸，从而具有优异的脱/氢性能。