Co@SiO2/C catalyst shielded by hierarchical shell for robust hydrogen production

NaBH4 hydrolysis under mild conditions is a promising solution for mobile hydrogen applications. However, the design and synthesis of cost-effective catalysts with sufficiently high activity and stability remain challenging. Herein, we report a facile approach to construct a series of SiO2 shielding cobalt-based catalysts with hierarchical active sites. Under optimized conditions, the hydrogen productivity of 18% Co@SiO2/C-300 is 8-fold higher than 18% Co/C catalyst without SiO2 shell. The incorporation of SiO2 shell enhances the partial oxidation of Co nanoparticles, resulting in the formation of a mesosphere CoOx overlayer covered by a SiO2 shell on Co particles. Meanwhile, the cobalt oxide on Co NPs could remain stable under reductive reaction conditions. The unique structural and electronic properties of the Co@SiO2/C configuration is demonstrated to enhance the activation of NaBH4 and H2O and promote H2 desorption, giving rise to a higher level of inherent activity and a relatively low reaction energy barrier.

Automated summary

The use of SiO2-shielded cobalt-based catalysts can enhance the activity and stability of NaBH4, leading to higher hydrogen productivity. The unique structural and electronic properties of these catalysts promote the reaction of NaBH4 and H2O, reducing the reaction energy barrier.