Geometrical Characterization of Glass Nanopipettes with Sub-10 nm Pore Diameter by Transmission Electron Microscopy

TL;DR

This paper presents methods for accurately characterizing sub-10 nm glass nanopipettes using transmission electron microscopy, overcoming deformation challenges caused by electron beam heating.

Contribution

It introduces novel specimen preparation techniques that prevent deformation of ultra-small nanopipettes during TEM analysis.

Findings

Successful TEM characterization of sub-10 nm nanopipettes

Development of deformation-free specimen preparation methods

Enhanced accuracy in geometrical measurements of nanopipettes

Abstract

Glass nanopipettes are widely used for various applications in nanosciences. In most of the applications, it is important to characterize their geometrical parameters, such as the aperture size and the inner cone angle at the tip region. For nanopipettes with sub-10 nm aperture and thin wall thickness, transmission electron microscopy (TEM) must be most instrumental in their precise geometrical measurement. However, this measurement has remained a challenge because heat generated by electron beam irradiation would largely deform sub-10-nm nanopipettes. Here we provide methods for preparing TEM specimens that do not cause deformation of such tiny nanopipettes.