Insights into van der Waals interaction between nanotubes and planar surfaces

Abstract

Advanced microscopic technology opens up the opportunity of investigating the microstructure of novel materials and devices. In particular, high-resolution Atomic Force Microscopy (AFM) allows for the atomistic observation of materials for a variety of applications. To improve the imaging capability, several tip morphologies have been proposed to be employed in the AFM field. Among such morphologies, the carbon nanotube (CNT) has drawn extensive attention in recent years due to its high resolution and mechanical strength in imaging conditions. However, the exact theoretical basis for employing the nanotube in advanced AFM remains elusive up to this point. Here, we explore the theoretical basis for employing the nanotube morphology in advanced AFM. To do so, van der Waals (vdW) interaction between the nanotube and a planar disc, a key factor for achieving high imaging sensitivity, is evaluated. The results unanimously verify that nanotube morphology has unprecedented advantages over traditional cone-shaped AFM tips.