EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Storing methane in clathrates is one of the most promising alternatives for transporting natural gas (NG) as it offers similar gas densities as liquefied and compressed NG while offering lower safety risks. However, the practical use of clathrates is limited given their unfavourable synthesis conditions, with sluggish kinetics and extreme operation factors (low temperatures and high pressures). Nanoporous materials have been suggested to be used for relenting clathrate’s formation conditions by increasing the contact area between the gas and water phases while preserving its CH4 volumetric storage. Yet, the choice of nanoporous materials to be employed as clathrate growing platforms is still rather arbitrary. Herein, we tackle this challenge in a systematic way by computationally exploring the stability of clathrates confined in a recent candidate for clathrate promotion, alkyl-graphited silica materials. Different materials settings were evaluated, including pore sizes, ligand densities and ligand types. Based on our findings we are able to propose key design criteria for nanoporous materials favouring the stability of a neighbouring clathrate phase namely larger pore sizes, high ligand densities, and smooth pore walls. With the atomistic insights provided in this work, we expect to pave the way towards the development of new bespoke nanomaterials designed to promote the formation of clathrates.