Maximizing methane and hydrogen delivery capacity by carbon and boron nitride nanoscrolls

The CH4 and H2 delivery capacity of carbon and boron nitride (BN) nanoscrolls was investigated, with a focus on optimizing the interlayer and van der Waals spacings to meet the U.S. Department of Energy (DOE) targets. Through computational simulations, the effects of interlayer spacing on CH4 and H2 adsorption were evaluated, revealing that while delivery quantities increase with interlayer spacing, achieving DOE targets remains a challenge for CH4. Notably, BN nanoscrolls exhibited higher adsorption capacities compared to carbon nanoscrolls, especially under low-pressure conditions. Conversely, carbon nanoscrolls displayed greater release quantities than BN nanoscrolls. For H2, delivery quantities met DOE targets at larger interlayer spacings, with carbon nanoscrolls requiring a spacing greater than 0.9 nm and BN nanoscrolls greater than 1.1 nm. For CH4 delivery, temperature optimization showed significant peaks in delivery for carbon nanoscrolls at 248 K. In contrast, BN nanoscrolls did not exhibit a peak in delivery. In carbon nanoscrolls, the optimal weight and volumetric capacities for methane delivery are 0.275 g/g and 182 cm3/cm3, respectively. Meanwhile, for hydrogen, the maximum delivery achieved is 8.26 wt% and 0.044 kg/L, which surpasses the DOE's storage target of 5.5 wt% and 0.04 kg/L. The study also highlighted the importance of structural parameter optimization, with a significant increase in weight delivery (>500%) and in volume delivery (>120%) for both gases.