(371r) Boosting Volumetric and Gravimetric H2 Storage Capacity of Carbon-Based Sorbents Through Tuning Surface Chemistry and Densification Approaches

With increasing energy demand from growing population, hydrogen is considered as one of the most sustainable energy carriers for the future. Significant advancements have been made over the past few years to produce hydrogen in a sustainable manner, however, the major bottleneck currently facing the hydrogen economy lies primarily in its transportation and storage.(DOE, 2020) Adsorbed gas storage (AGS) technology offers a much safer and more economic storage option than existing cryogenic cooling or compression methods for hydrogen storage and transport. However, the current sorbents examined as H₂-AGS candidates still suffer from low deliverable capacity. Therefore, to enhance the hydrogen density per volume of storage tank and to meet the DOE’s set targets, extensive research on nano-porous materials and storage conditions is required. In this research, we focused our attention on exceptionally high-surface area activated carbon and graphitic carbon nanosheets to further enhance the binding energy and adsorption capacity over a pressure range of 0-100 bar and varied charge-discharge temperatures via (i) surface functionalization with light–metal dopants such as Li, Na and K, and (ii) carbon exfoliation with ionic liquids, and (ii) sorbent densification approaches. Our results indicated the effectiveness of these approaches to enhance both gravimetric and volumetric hydrogen capacity relative to the pristine sorbents.

Keywords: Adsorption, Nanomaterials, Hydrogen storage

Reference:

DOE. (2020). Foundational Science for Carbon-Neutral Hydrogen Technologies. DOE_BES Roundtable, 1999(December), 1–6.