Reporting the sensitivities and resolutions of CNT-based resonators for mass sensing

摘要

The attitude of the science of mass sensors is to design highly mass sensitive nano-devices along with nano-devices that can operate at distinct sensitivity and resolution levels. Because they can achieve very high frequency shifts when very small masses are added to their surfaces, carbon nanotubes (CNTs) are considered as the most promising material candidate that can be used in designing mass sensors. To design and recommend a CNT for specific sensitivity and resolution levels, experimental trials are usually utilized. This motivated us to report the sensitivities and resolutions of CNTs-based resonators for mass sensing applications. An accurate mathematical model is proposed with considering the atomic packing and the lattice dynamics of CNTs. In the context of this model, the elastic properties of CNTs are obtained accounting for their phonon dispersions. The derived model is then used to report the sensitivities and resolutions of CNTs as functions of the CNT length and diameter. Recommended dimensions for CNTs with resolutions equal to the atomic mass of elements including B, Ca, C, Cr, Li, Mg, Si, Ti, and Zr are also determined. The performed analyses provide the necessary guidelines to design efficient mass sensors and mechanical mass spectrometers with different sensitivity and resolution levels. (C) 2016 Elsevier Ltd. All rights reserved.