Methionine aqueous solution loaded vermiculite/MXene aerogels for efficient CO2 storage via gas hydrate

Abstract

Gas hydrate provides an ideal way for CO2 capture and storage using water by forming cages via an environment-friendly and energy-efficient hydrate formation process. However, the practical utilization and upscaling of hydrate-based gas storage are impeded by the slow formation kinetics of gas hydrate due to the limited multiphase interface for mass transfer and reaction. Herein, we demonstrated a simple strategy to fabricate composite aerogels assembled of natural vermiculite and MXene nanosheets as the ideal substrate for boosting CO2 hydrate formation. The structure and surface compositions of vermiculite/MXene composite aerogels were analyzed by XRD, FT-IR, SEM, and XPS. It shows that monolithic pore structures and surface functional groups can be finely tuned by controlling the mass ratio of vermiculite and MXene, leading to an outstanding CO2 storage capacity of 136.9 v/v (corresponding to 0.121 mol CO2/mol water) with enhanced hydrate formation kinetics. The degree of water saturation plays the most vital role in controlling formation kinetics and gas storage capacity. This work provides a reliable method to synthesize aerogels for boosting CO2 storage via enhanced hydrate formation and sheds light on the structure performance relationship of porous materials for enhancing gas hydrate formation.