IEC TS 62607-6-33:2025, which is a Technical Specification, establishes a standardized method to determine the key control characteristic
• defect density (%, nm2)
of single layer graphene films by
• electron energy loss spectroscopy (EELS in transmission electron microscopy (TEM)).
This document outlines a method for quantitative measurement of defects in graphene at the nanoscale.
The method specified in this document is applicable to single layer graphene acquired via chemical vapour deposition (CVD), roll-to-roll production and exfoliated graphene flakes to estimate the defect density.
In order to obtain reliable data, it is essential that the procedure is consistent for each specified condition from the preparation of the TEM specimen to its observation. It is essential to maintain the spatial resolution below 1 nm by alignment of the beam. The dispersion value, which covers the entire energy loss near edge structure (ELNES) region of the carbon-K edge and maintains the highest energy resolution corresponds to 0,1 eV/ch. Defects in graphene are determined by measuring the spectral differences between sp2 hybridized and sp2/sp3 hybridized atoms, which are obtained by calculating the amplitude ratio of the π* and σ* orbital spectra.
