Piezoelectric Response of Multi-Walled Carbon Nanotubes

Abstract

Recent studies in nanopiezotronics have indicated that strained graphene may exhibit abnormal flexoelectric and piezoelectric properties. Similar assumptions have been made with regard to the properties of carbon nanotubes (CNTs), however, this has not so far been confirmed. This paper presents the results of our experimental studies confirming the occurrence of a surface piezoelectric effect in multi-walled CNTs under a non-uniform strain. Using atomic force microscopy, we demonstrated the piezoelectric response of multi-walled CNTs under compression and bending. The current generated by deforming an individual CNT was shown to be −24 nA. The value of the surface potential at the top of the bundle of strained CNTs varied from 268 mV to −110 mV, depending on strain type and magnitude. We showed that the maximum values of the current and the surface potential can be achieved when longitudinal strain predominates in a CNT. However, increasing the bending strain of CNTs does not lead to a significant increase in current and surface potential, due to the mutual compensation of piezoelectric charges concentrated on the CNT side walls. The results of the study offer a number of opportunities and challenges for further fundamental research on the piezoelectric properties of carbon nanotubes as well as for the development of advanced CNT-based nanopiezotronic devices.

Scanning Probe Techniques for Characterization of Vertically Aligned Carbon Nanotubes

“…Recent work in the field of investigation of electromechanical properties of carbon nanostructures has shown the possibility of manifesting flexoelectric and piezoelectric effects in them [3,[43][44][45][46]. In this connection, an urgent task was the development of a technique for determining the piezoelectric response of vertically aligned carbon nanotubes because the use of the piezoresponse force microscopy in this case is difficult.…”

“…For this sample, the measurements of Figure 12. Study of the piezoelectric response of the VA CNT: (a) schematic of the measurement process; and (b) currenttime dependence of a VA CNT and the corresponding AFM force spectroscopy [46].…”

Application of Probe Nanotechnologies for Memristor Structures Formation and Characterization

“…It should be noted that the values of R HRS and R LRS of the VA CNT are 2-3 times lower at U < 0 than at U > 0. It is due to the fact that associated with the occurrence of a piezoelectric charge, internal field of the nanotube [33,34] is co-directed with an external electric field, and accordingly, reduces the resistance of the VA CNT when a negative voltage is applied and is oppositely directed and increases the total resistance of the VA CNT when a positive voltage is applied.…”

Modeling of Catalytic Centers Formation Processes during Annealing of Multilayer Nanosized Metal Films for Carbon Nanotubes Growth

“…Since the discovery of carbon nanotubes (CNTs) [1], their properties, not fully studied, have generated multiple research projects (since 1991 more than 135,000 articles have been published). The discovered unique properties [2][3][4] have shown promise for the use of CNTs as functional elements of emission nanoelectronic devices [5,6], memory elements [7,8], interconnects [9], as solar-driven water evaporation [10,11], generation of electricity [12], solar cells [13] and applications in the field of nanopiezotronics [14]. However, the creation of a broad range of CNTs-based devices requires their production with a given orientation relative to the substrate, sizes, density, properties and their location in areas determined by the device design [15].…”