Although considerable efforts have been made to direct nanoscale linear or rotary motion for potential applications in energy conversion and mass transport, generating continuous and cyclic motion in a controlled manner at small scales remains extremely challenging. Based on molecular dynamics simulations, here we propose a nanomotor that can produce continuous cyclic motion. The motor consists of a thick carbon nanotube horizontally clamped between two parallel gold substrates subject to antisymmetric thermal gradients. The speed and motion direction of the motor can be well controlled by the applied thermal field. The driving mechanism is attributed to thermophoresis on solid surfaces, and further confirmed by an analytical model. The present motor design may have general implications not only for developing nanomotors that generate controllable continuous motion but also for developing new techniques of continuously converting other forms of energy into mechanical work.

尽管已经做出了巨大努力来引导纳米级线性或旋转运动以用于能量转换和质量传输中的潜在应用，但是以可控的方式在小规模上产生连续和循环运动仍然极具挑战性。基于分子动力学模拟，我们在此提出一种可以产生连续循环运动的纳米电机。电机由水平固定在两个平行的金基板之间的厚碳纳米管组成，该碳纳米管受到反对称热梯度的影响。电机的速度和运动方向可以通过施加的热场很好地控制。该驱动机制归因于固体表面上的热泳，并由分析模型进一步证实。