Preparation of pompon-like Co-B nanoalloy by a room-temperature solid-state-reaction as a catalyst for hydrolysis of borohydride solution

Pompon-like Co-B alloy composed of nanosheets with a large specific surface area of 202.4 m² g^?1 was synthesized via a facile room-temperature solid-state-reaction. By changing the mass ratios of CoCl₂·6H₂O to CO(NH₂)₂ in the synthesis, the morphology of the Co-B alloy can be controlled. Correspondingly, the specific surface area can increase from ca. 43.4–202.4 m² g^?1. When the pompon-like Co-B severs as a catalyst for the hydrolysis of NaBH₄, the hydrogen generation rate can be up to $8\text{.}26{\text{L}}_{\text{hydrogen}}{\text{min}}^{\mathrm{?}1}{{\text{g}}_{\text{catalyst}}}^{\mathrm{?}1}$. This value is larger compared with those of many other Co-B nanoalloys in previous reports. Additionally, the corresponding activated energy for the hydrolytic reaction is as low as 25 kJ mol^?1, hinting that the pompon-like Co-B catalyst possesses superior catalytic performance. The pompon-like Co-B alloy has the advantages of low cost, good recoverability, as well as high activity, which may find practical application in NaBH₄ hydrolysis for hydrogen production.