Nanospring from partly hydrogenated graphene ribbon: A molecular dynamics study

In this work, a torque nanospring model built from a piece of graphene featured with single-sided hydrogenated graphene ribbons (H1GRs) is proposed. The model consists of two long H1GRs joined by three short pieces of graphene (Fixed part, M-part and Moving part shown in Fig. 1a). The two H1GRs have opposite hydrogenated surfaces. They wrap around the M-part to form a scroll after relaxation. The remained two short end pieces (Fixed part and Moving part) connecting to H1GRs are used for loading. If the self-bended nanoscroll turns to flat, its two ends must be under tension. In this study, the relevant characteristics of the nanospring are investigated. The shrinkage of the nanospring versus its internal tension (T) at an end is evaluated by molecular dynamics simulations. And the characteristics of the nanospring are investigated. It was found that T is at the level of 100 meV/Ų per angstrom. The component in shrinking direction depends slightly on either temperature or the shrinking speed. T reduces less than 10% when randomly removing 20% C[sbnd]H bonds from the two H1GRs. When the removal percentage is less than 30%, a nanospring can still be formed. These characteristics make the nanospring of potentials in the applications of actuators, nanobalance, switch, etc.