Energy evolution mechanism of nanonetwork from hydrogenated graphene scrolls

When graphene is hydrogenated on one side, it will curl due to carbon-hydrogen bonding, and the potential energy will be stored at this time. When fabricating a network by connecting the hydrogenated graphene ribbons (HGRs) via central carbon nanotubes (CNTs), the network has excellent properties in strain engineering. How-ever, after loading and then unloading, the nano network will store lower energy. Molecular dynamics simu-lations were used to evaluate the energy loss of such networks, with consideration of the network size, loading -unloading rate, ambient temperature, and the length of the HGRs. It is found that two reasons cause the energy loss. One is the void defects generated in the network during the unloading process. The other is that the HGRs change from J4-scrolls to J2-scrolls, or the mixture of J4-and J2-scrolls, or even become flat and simply attach. Briefly, the energy loss rate converges at-14 % when the network contains more than 5 x 5 cells. At lower temperatures, the energy loss of a network with a large number of unit cells becomes higher, such as a 6 x 6 network at 10 K, with a maximum energy loss rate of-20 %. The network made from longer HGRs has a lower capacity for energy storage. These findings facilitate the potential application of the nanonetwork in nanodevices.

Automated summary

This study investigates the energy loss issue of hydrogenated graphene networks and identifies two reasons for the energy loss. The findings contribute to the potential application of nanonetworks in nanodevices.