The significant challenges encountered when replacing precious-metal-based catalysts in the hydrolysis of sodium borohydride (NaBH₄) are related to the low durability and efficiency of nonprecious metals. In this study, we synthesized nitrogen-doped mesoporous graphitic carbon encapsulated cobalt nanoparticles ([email protected]) with a core–shell structure by the carbonization of ethylenediaminetetraacetic acid (EDTA)-derived carbon. These structures were then used as catalysts for the hydrolisis of NaBH₄. Among different calcination temperatures, 500°C resulted in the best catalytic activity, with a hydrogen production rate of 3575 mL min^-1 g^-1 at 25±0.1 °C and low activation energy of 35.2 kJ mol^-1 for NaBH₄ hydrolysis. The maximum hydrogen production rate using the cobalt-based complex catalyst was about three-fold that achieved using the pure cobalt catalyst. We found that the complex catalyst showed high durability, retaining 82.5% of the initial catalytic activity after 20 hydrolysis cycles. The catalyst was also magnetic, making it 100% recyclable. Density functional theory (DFT) calculations showed that the graphitic carbon shell promoted electron penetration from the Co nanoparticles into the graphitic carbon surface, which prevented oxidation of the Co nanoparticles, while the Co core provided better conductivity. This work provides a novel method for the synthesis of shelled-structure catalysts, which have potential applications in the hydrolysis of sodium borohydride.

在硼氢化钠（NaBH ₄）的水解中替代贵金属基催化剂时遇到的重大挑战与非贵金属的低耐久性和效率有关。在这项研究中，我们通过乙二胺四乙酸（EDTA）衍生的碳的碳化合成了具有核-壳结构的氮掺杂的介孔石墨碳封装的钴纳米颗粒（[受电子邮件保护]）。然后将这些结构用作NaBH ₄水解的催化剂。在不同的煅烧温度中，500°C导致最佳的催化活性，在25±0.1°C时产氢率为3575 mL min ^-1 g ^-1，而活化能为35.2 kJ mol ^-1用于NaBH ₄水解。使用钴基络合物催化剂的最大氢气产生速率约为使用纯钴催化剂所达到的三倍。我们发现，复合催化剂显示出很高的耐久性，在20个水解循环后保留了初始催化活性的82.5％。催化剂也是磁性的，使其100％可回收。密度泛函理论（DFT）计算表明，石墨碳壳促进了电子从Co纳米颗粒渗透到石墨碳表面，从而阻止了Co纳米颗粒的氧化，而Co核提供了更好的导电性。这项工作提供了一种新的有壳结构催化剂的合成方法，该方法在硼氢化钠的水解中具有潜在的应用。