关键词: 水合物储氢, 分子动力学, 形成机理, 分子扩散, 孔穴结构稳定性, 促进剂

Abstract:

Under the pressing “dual-carbon” goals and the green transition of energy structures, hydrogen energy has garnered widespread attention due to its abundant sources, high combustion calorific value, green and low-carbon properties, and broad applicability. As an emerging solid-state hydrogen storage technology, hydrogen storage via hydrates demonstrates significant advantages in safety and high storage density, showing immense developmental prospects and application value. However, the advancement of hydrate-based hydrogen storage technology is currently hindered by critical challenges, including stringent formation conditions, slow growth rates, and unstable hydrogen storage density. The root cause of these bottlenecks lies in the unclear molecular dynamics behaviors and mechanisms governing the interactions among hydrogen molecules, water molecules, and promoter molecules during the hydrogen storage process. To address these issues, this study focuses on the molecular dynamics behaviors and mechanisms in hydrogen storage hydrates. Specifically, it comprehensively reviews the kinetic growth mechanisms of hydrogen hydrates under the influence of promoters, elucidating the stable filling of hydrate cages and the inter-cage diffusion behavior of molecules within promoter-enhanced systems. The findings provide molecular-level insights to support the refinement of thermodynamic and kinetic theoretical frameworks for hydrogen hydrate formation facilitated by promoters. This research aims to advance the efficient hydrogen storage in cage-like hydrates with promoter assistance, thereby accelerating the development and practical application of hydrate-based hydrogen storage technologies.

Key words: hydrogen hydrate, molecular dynamics behavior, formation mechanism, molecular diffusion, stability of cavity structure, promoter