Mechanism of C60 rotation and translation on hexagonal boron-nitride monolayer

Abstract

Newly synthesized nanocars have shown great potential to transport molecular payloads. Since wheels of nanocars dominate their motion, the study of the wheels helps us to design a suitable surface for them. We investigated C60 thermal diffusion on the hexagonal boron-nitride (h-BN) monolayer as the wheel of nanocars. We calculated C60 potential energy variation during the translational and rotational motions at different points on the substrate. The study of the energy barriers and diffusion coefficients of the molecule at different temperatures indicated three noticeable changes in the C60 motion regime. C60 starts to slide on the surface at 30 K–40 K, slides freely on the boron-nitride monolayer at 100 K–150 K, and shows rolling motions at temperatures higher than 500 K. The anomaly parameter of the motion reveals that C60 has a diffusive motion on the boron-nitride substrate at low temperatures and experiences superdiffusion with Levy flight motions at higher temperatures. A comparison of the fullerene motion on the boron-nitride and graphene surfaces demonstrated that the analogous structure of the graphene and hexagonal boron-nitride led to similar characteristics such as anomaly parameters and the temperatures at which the motion regime changes. The results of this study empower us to predict that fullerene prefers to move on boron-nitride sections on a hybrid substrate composed of graphene and boron-nitride. This property can be utilized to design pathways or regions on a surface to steer or trap the C60 or other molecular machines, which is a step toward directional transportation at the molecular scale.

Nanocar swarm movement on graphene surfaces

“…8 Different investigations have evaluated the surface motion of single molecules over the recent years. [9][10][11][12][13] Scanning tunneling microscopy (STM) is commonly utilized in the experimental observations from earlier works conducted by James Tour and his colleagues 14 to the recent study on the rotation of nanocars by applying an electric field. 8 Although the STM technique is a dominant tool for observing and transporting the molecules on a surface, the surface motion of nanocars has been monitored by fluorescence imaging in previous experiments.…”

Collective movement and thermal stability of fullerene clusters on the graphene layer

“…[2][3][4][5][6][7][8][9] These studies include the mobility of small molecules or large organic ones such as artificial nano-machines on different surfaces. [10][11][12][13][14][15][16] Such molecular machines (named nanocars) are capable of carrying payloads on the surface. 17 The aggregation of carbon nanostructures such as fullerenes has also shown potential as nanocarriers in the delivery of molecules.…”

Investigation of fullerene motion on thermally activated gold substrates with different shapes

“…Four or three-wheeled nano-machines with C 60 as a wheel were fabricated significantly in previous studies of these nano-machines 5 . Vaezi et al 18 investigated the motion of C 60 molecule on the boron-nitride substrate at different temperatures. They indicated that as the temperature increased, the rolling motion became more significant than the siding motion, and the range of the movement and diffusion coefficients became greater.…”