Dynamic behavior of a rotary nanomotor in argon environments

Abstract

When argon is used as a protecting gas in the fabrication or working environment of a nanodevice, absorption of some argon atoms onto the surface of the device lead to different responses. In this work, the rotation of the rotor in a carbon nanotube (CNT)-based rotary nanomotor in argon environment is investigated. In the rotary nanomotor, two outer CNTs act as the stator and are used to constrain the inner CNT (i.e., the rotor). The rotor is driven to rotate by the stator due to their collision during thermal vibration of their atoms. A stable rotational frequency (SRF) of the rotor occurs when the rotor reaches a dynamic equilibrium state. The value of the SRF decreases exponentially with an increase in the initial argon density. At dynamic equilibrium date, some of the argon atoms rotate synchronously with the rotor when they are absorbed onto either internal or external surface of the rotor. The interaction between the rest of the argon atoms and the rotor is stronger at higher densities of argon, resulting in lower values of the SRF. These principles provide insight for future experimentation and fabrication of such rotary nanomotor.

Dynamic Behavior of Rotation Transmission Nano-System in Helium Environment: A Molecular Dynamics Study

“…The transmission behavior of the RTS at the 300 K has been analyzed in Section 2.2. It is well known that temperature is one of the major factors that affect the transmission performance of the RTS [43,53,54]. Hence, in order to investigate the influence of system temperatures on the transmission performance of RTS in helium environment, three temperatures of 150 K, 300 K, and 500 K are considered.…”

“…Therefore, when the system temperature rises within a certain range, the interlayer van der Waals effects and the end effects of RTS increase, so the driving force of the rotor increases with the increase of temperature [43]. The rotor rotational speed will accelerate as the environmental temperature rises [53,54]. When the system temperature rises to 500 K, although the skin friction drag of helium increases with the increase in temperature, a higher critical working density range of RTS is allowed because of the greater driving force with the increasing temperature.…”

“…Shi et al [ 52 ] explored the efficiency of CNT-based RTS in water solution, and they manipulated the transmission efficiency of RTS through the water-rotor interaction in the water box. Cai et al [ 53 ] and Shi et al [ 54 ] studied the rotation behavior of nanomotors and nanorings in argon environments, respectively. The results show that in a higher temperature environment, the nanomotors and the nanorings have a higher rotation frequency than that at a lower temperature.…”

“…When the RTS works in a helium environment, randomly moving helium atoms will attract or repel the atoms on the nanotubes, thereby generating fluid friction and affecting the transmission performance of the RTS. Clearly, it can be concluded from aforementioned studies [43,53,54] that the temperature and gas densities have a significant influence on the nano-system in a medium environment. Therefore, using the classical MD method, the influences of the system temperatures, helium densities and simulation box sizes on the transmission behavior of RTS in a helium environment are especially investigated, aiming at providing guidance for the potential applications of RTS in nanodevices.…”

Effects of Radius and Length on the Nanomotor Rotors in Aqueous Solution Driven by the Rotating Electric Field

“…Nanomotors − are nanoscale devices capable of producing linear and (or) rotational motion. Recently, there have been certain accomplishments observed on driving nanomotors through various methods in a nonsolution environment. − For example, Wang et al developed an ultrasound-driven DC nanomotor. The nanomotor has a good response to ultrasound and can collect and convert energy from the surrounding environment.…”