Can carbon and boron nitride nanoscrolls be good methane storage materials?

Abstract

We perform molecular simulations to explore methane adsorption on carbon and boron nitride (BN) nanoscrolls, highlighting the impact of radius, pressure, and temperature on adsorption performance. Surprisingly, increasing nanoscroll layers, particularly in BN nanoscrolls, does not enhance methane adsorption but rather reduces release capacity. Our molecular simulations reveal a linear relationship between methane release and structural parameters of both carbon and BN nanoscrolls, with carbon nanoscrolls showing higher release independent of structure, while BN nanoscrolls’ release varies with porosity, pore volume, and material density. The stability of this relationship is evident despite limited variability in structural parameters, pointing to elemental composition and molecular force fields as the key determinants of methane release behavior. At 30 MPa, BN nanoscrolls’ volume adsorption marginally meets the DOE target, while carbon nanoscrolls show significant, yet insufficient, progress toward the same goal. Temperature studies indicate that lower temperatures benefit carbon nanoscrolls’ adsorption and release but negatively impact BN nanoscrolls’ release. Our results indicate that while both types of nanoscrolls can meet the DOE’s targets for methane adsorption at low temperatures of 208 K and high pressures of 30 MPa, and have release capacities close to the targets, BN nanoscrolls, unlike carbon nanoscrolls, exhibit higher methane adsorption at low pressures of 0.1 MPa. This leads to more complex release phenomena for BN nanoscrolls. These findings provide critical insights, guiding the design and optimization of nanoscroll materials for enhanced methane adsorption and release in gas storage applications.