The development of highly-efficient and noble-metal-free catalysts with low cost and high durability for hydrogen evolution reaction (HER) is of great importance to many energy-related technologies. This work reports that nitrogen-doped carbon coated Co nanoparticles encapsulated in bamboo-like nitrogen-doped carbon nanotubes (Co@NC/B-NCNTs), synthesized by a simple calcination of Co(NO₃)₂, melamine and P123, is a promising catalyst for HER in both acidic and alkaline solutions. In acidic solution, the Co@NC/B-NCNTs has the HER onset potential of ∼0 V and only needs an overpotential of 7 mV to drive the current density of 10 mA cm⁻². Its HER catalytic activity is very close to that of Pt/C. In alkaline solution, its onset potential and overpotential to drive 10 mA cm⁻² are 100 and 182 mV, respectively. Both the values are lower than those of many other catalysts reported. The DFT calculations show electronic coupling between Co nanoparticles and NC layer plays an important role in high catalytic activity of Co@NC/B-NCNTs. The Co nanoparticles can change the charge density distribution of the outer NC layer, affecting its properties for hydrogen adsorption and desorption. Additionally, the pyridinic N in the outer NC layer is calculated to be a promising active site for HER.

对于许多与能源相关的技术而言，开发低成本，高耐久性的高效，无贵金属的氢气分解反应（HER）催化剂是非常重要的。这项工作报告说，通过简单煅烧Co（NO ₃）₂，三聚氰胺和P123合成的包裹在竹状氮掺杂碳纳米管（Co @ NC / B-NCNTs）中的氮掺杂碳包覆的Co纳米粒子是一种在酸性和碱性溶液中都可用于HER。在酸性溶液中，Co @ NC / B-NCNT的HER起始电势约为0 V，仅需7 mV的超电势即可驱动10 mA cm ^-2的电流密度。它的HER催化活性非常接近Pt / C。在碱性溶液中，其驱动10 mA cm ^-2的起始电位和过电位分别为100和182 mV。这两个值均低于报道的许多其他催化剂的值。DFT计算表明，Co纳米粒子与NC层之间的电子耦合在Co @ NC / B-NCNTs的高催化活性中起着重要作用。Co纳米粒子可以改变外部NC层的电荷密度分布，从而影响其氢吸附和解吸的性能。此外，外部NC层中的吡啶N被计算为有希望的HER活性位点。