IEC TS 62607-6-14:2020

Nanomanufacturing - Key control characteristics - Part 6-14: Graphene-based material - Defect level: Raman spectroscopy

IEC TS 62607-6-14:2020 establishes a standardized method to determine the structural key control characteristic
• defect level
for powders consisting of graphene-based material by
• Raman spectroscopy.
The defect level is derived by the intensity ratio of the D+D′ band and 2D band in Raman spectrum, ID+D′/I2D.
• The defect level determined in accordance with this document will be listed as a key control characteristic in the blank detail specification for graphene IEC 62565-3-1 for graphene powder.
• The method is applicable for graphene powder or graphene-based material, e.g. reduced graphene oxide (rGO), bilayer graphene, trilayer graphene and few-layer graphene.
• Typical application areas are quality control and classification for graphene manufacturers, and product selection for downstream users.
• The method described in this document is appropriate if the physical form of graphene is powder.

General Information

• Status: Published
• Publication Date: 26-Oct-2020
• ICS: 07.120 - Nanotechnologies
• Technical Committee: TC 113 - Nanotechnology for electrotechnical products and systems
• Drafting Committee: PT 62607-6-14 - TC 113/PT 62607-6-14
• Current Stage: PPUB - Publication issued
• Start Date: 27-Oct-2020
• Completion Date: 12-Nov-2020

Standards Content (Sample)

IEC TS 62607-6-14 ®
Edition 1.0 2020-10
TECHNICAL
SPECIFICATION
colour
inside
Nanomanufacturing – Key control characteristics –
Part 6-14: Graphene-based material – Defect level: Raman spectroscopy

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

IEC Central Office Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
The advanced search enables to find IEC publications by a The world's leading online dictionary on electrotechnology,
variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Glossary - std.iec.ch/glossary
details all new publications released. Available online and 67 000 electrotechnical terminology entries in English and
once a month by email. French extracted from the Terms and Definitions clause of
IEC publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
If you wish to give us your feedback on this publication or CISPR.

need further assistance, please contact the Customer Service

Centre: [e-mail].
IEC TS 62607-6-14 ®
Edition 1.0 2020-10
TECHNICAL
SPECIFICATION
colour
inside
Nanomanufacturing – Key control characteristics –

Part 6-14: Graphene-based material – Defect level: Raman spectroscopy

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 07.120 ISBN 978-2-8322-8940-2

– 2 – IEC TS 62607-6-14:2020  IEC:2020
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 8
3.1 General terms . 8
3.2 Key control characteristics measured in accordance with this document . 11
4 General . 11
4.1 Measurement principle . 11
4.2 Sample preparation method . 12
4.3 Description of measurement equipment/apparatus . 12
4.4 Supporting materials . 12
4.5 Ambient conditions during measurement . 12
5 Measurement procedure . 13
5.1 Calibration of measurement equipment . 13
5.2 Detailed protocol of the measurement procedure . 13
5.3 Measurement accuracy . 13
5.4 Measurement uncertainty source . 13
6 Sampling plan . 13
7 Data analysis / interpretation of results . 13
8 Results to be reported . 14
8.1 General . 14
8.2 Product/sample identification . 14
8.3 Test conditions . 14
8.4 Measurement specific information . 14
8.5 Test results . 14
Annex A (informative) Recommended format of the test report . 15
Annex B (informative) Sampling plan . 17
Annex C (informative) Case study: measurement and data analysis . 18
C.1 Step 1: sample preparation . 18
C.2 Step 2: Raman test . 18
C.3 Step 3: Raman spectra processing . 18
C.4 Step 4: Data analysis . 19
Annex D (informative) Why use the intensity ratio I /I for defect level
D+D′ 2D
characterization of graphene powder? . 22
D.1 Interpretation of characteristic bands in the Raman spectrum of graphene
and Raman scattering mechanism . 22
D.2 Example – Influence of edges in the Raman spectrum of graphene . 22
D.3 Example – Influence of defect in the Raman spectrum of single layer
graphene . 24
D.4 Example – Raman characteristics of reduced graphene sheet . 26
D.5 Conclusion . 27
Bibliography . 28

Figure 1 – Schematic diagram of Raman scattering processes in realistic graphene
material . 6

Figure 2 – Different packing configurations of graphene flakes in film (left) and powder
(right) . 6
Figure 3 – Schematic drawing of Raman spectra of defective graphene (upper) and

pristine graphene (bottom) . 12
Figure 4 – Schematic drawing of sample preparation method . 12
Figure B.1 – Schematic drawing of five-point-sampling method . 17
Figure B.2 – Location of measurement points . 17
Figure C.1 – The field view of graphene sample beneath Raman microscope . 18
Figure C.2 – The procedure of Raman spectrum processing . 19
Figure C.3 – Typical Raman spectrum after processing . 20
Figure C.4 – The overall defect level of one test sample . 21
Figure C.5 – Measurement results of different testing organizations . 21
Figure D.1 – Characteristic bands in the Raman spectrum of graphene and Raman
processes [6] . 22
Figure D.2 – Raman spectra from the edges of a monolayer graphene sample [9] . 23
Figure D.3 – Raman spectra obtained from monolayer graphene samples with
hexagonal and circular holes [10] . 23
Figure D.4 – Raman spectra for four different ion doses in graphene [1] . 24
Figure D.5 – E [I /I ] as a function of L [2] . 24
L D G D
Figure D.6 – (a) Definition of the activated A-region (green) and structurally-
disordered S-region (red). (b-e) Snapshots of the structural evolution of the graphene
sheet for different defect concentrations [1] . 25
Figure D.7 – Evolution of 2D and other second-order bands with increasing ion doses
[5] . 25
Figure D.8 – Raman characteristics of as-made graphene sheet and different types of
reduced graphene sheet film samples: (a) Raman spectra; (b) D/G intensity ratios; (c)
S3/2D intensity ratios [7] . 26
Figure D.9 – Resistivity of as-made graphene sheet and different types of reduced
graphene sheet [7] . 26

Table A.1 – Product identification (in accordance with IEC 62565-3-1) . 15
Table A.2 – General material description (in accordance with IEC 62565-3-1). 15
Table A.3 – Information related with test . 16
Table A.4 – Measurement results . 16
Table C.1 – Average I ′/I of each test point . 20
D+D 2D
– 4 – IEC TS 62607-6-14:2020  IEC:2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
NANOMANUFACTURING – KEY CONTROL CHARACTERISTICS –

Part 6-14: Graphene-based material – Defect level: Raman spectroscopy

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
The main task of IEC technical committees is to prepare International Standards. In exceptional
circumstances, a technical committee may propose the publication of a Technical Specification
when
• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical Specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC TS 62607-6-14, which is a Technical Specification, has been prepared by IEC technical
committee 113: Nanotechnology for electrotechnical products and systems.

The text of this Technical Specification is based on the following documents:
Enquiry draft Report on voting
113/495/DTS 113/536/RVDTS
Full information on the voting for the approval of this Technical Specification can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC TS 62607 series, published under the general title
Nanomanufacturing – Key control characteristics, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

– 6 – IEC TS 62607-6-14:2020  IEC:2020
INTRODUCTION
Graphene has been intensively studied by researchers from both academic and industrial
communities due to its unique properties, which include exceptional thermal conductivity, great
strength and excellent transparency. Defects in graphene influence its optical and magnetic
performance, electronic structure and thermal conductivity, thus influencing its applications.
Therefore, defect is a key control characteristic for the fabrication of high-quality graphene for
desired applications.
One of the most useful methods to evaluate defect level in graphene is Raman spectroscopy,
which is sensitive to the structure of samples. This method is efficient, non-contact and well-
understood. The defect states and boundary states of realistic graphene material will induce a
series of Raman scattering processes (Figure 1). Some of scattering processes are only
associated with defective states, which are used in this document to analyse defect level in
graphene powder.
Figure 1 – Schematic diagram of Raman scattering
processes in realistic graphene material
Commercialized graphene samples can be classified by their physical forms as graphene film,
graphene powder and graphene solution. Figure 2 shows the schematic packing configurations
of graphene flakes in graphene film (left side of Figure 2) and graphene powder (right side of
Figure 2) and their corresponding SEM images.

Figure 2 – Different packing configurations of graphene
flakes in film (left) and powder (right)

Usually, defects in graphene films are characterized by the intensity ratio of two principle
bands – D band and G band – in Raman spectra (symbolized by I /I ) [1],[2]. However, in
D G
graphene powders consisting of flakes with sizes below 10 µm there are numerous edges and
boundary states, which all contribute to the D-band signal and make its correlation to various
defects problematic. The D-band intensity could result from the contribution of edges, boundary
states or defects, so it is not appropriate to determine the defect level of graphene powder with
the parameter I /I .
D G
D+D′ band is only relevant with defects in graphene powder, but not with edges and boundary
states. Therefore, in order to characterize defect level in graphene powder, the intensity ratio
of D+D′ and 2D bands (symbolized by I /I ) is proposed as a more relevant parameter in
D+D′ 2D
this document. Detailed information can be found in Annex D.

– 8 – IEC TS 62607-6-14:2020  IEC:2020
NANOMANUFACTURING –
KEY CONTROL CHARACTERISTICS –
Part 6-14: Graphene-based material – Defect level: Raman spectroscopy

1 Scope
This part of IEC TS 62607 establishes a standardized method to determine the structural key
control characteristic
• defect level
for powders consisting of graphene-based material by
• Raman spectroscopy.
The defect level is derived by the intensity ratio of the D+D′ band and 2D band in Raman
spectrum, I /I .
D+D′ 2D
• The defect level determined in accordance with this document will be listed as a key control
characteristic in the blank detail specification for graphene IEC 62565-3-1 for graphene
powder.
• The method is applicable for graphene powder or graphene-based material, e.g. reduced
graphene oxide (rGO), bilayer graphene, trilayer graphene and few-layer graphene.
• Typical application areas are quality control and classification for graphene manufacturers,
and product selection for downstream users.
• The method described in this document is appropriate if the physical form of graphene is
powder.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1 General terms
3.1.1
two-dimensional material
2D material
material, consisting of one or several layers with the atoms in each layer strongly bonded to
neighbouring atoms in the same layer, which has one dimension, its thickness, in the nanoscale
or smaller and the other two dimensions generally at larger scales
Note 1 to entry: The number of layers when a two-dimensional material becomes a bulk material varies depending
on both the material being measured and its properties. In the case of graphene layers, it is a two-dimensional
material up to 10 layers thick for electrical measurements, beyond which the electrical properties of the material are
not distinct from those for the bulk (also known as graphite).
Note 2 to entry: Interlayer bonding is distinct from and weaker than intralayer bonding.

Note 3 to entry: Each layer may contain more than one element.
Note 4 to entry: A two-dimensional material can be a nanoplate.
[SOURCE: ISO/TS 80004-13:2017, 3.1.1.1]
3.1.2
graphene
graphene layer
single-layer graphene
monolayer graphene
single layer of carbon atoms with each atom bound to three neighbours in a honeycomb
structure
Note 1 to entry: It is an important building block of many carbon nano-objects.
Note 2 to entry: As graphene is a single layer, it is also sometimes called monolayer graphene or single-layer
graphene and abbreviated as 1LG to distinguish it from bilayer graphene (2LG) and few-layered graphene (FLG).
Note 3 to entry: Graphene has edges and can have defects and grain boundaries where the bonding is disrupted.
[SOURCE: ISO/TS 80004-13:2017, 3.1.2.1]
3.1.3
graphene-based material
GBM
graphene material
grouping of carbon-based 2D materials that include one or more of graphene, bilayer graphene,
few-layer graphene, graphene nanoplate, and functionalized variations thereof as well as
graphene oxide and reduced graphene oxide.
Note 1 to entry: "Graphene material" is a short name for graphene-based material.
3.1.4
bilayer graphene
two-dimensional material consisting of two well-defined stacked graphene layers
Note 1 to entry: If the stacking registry is known, it can be specified separately, for example, as “Bernal stacked
bilayer graphene”.
[SOURCE: ISO/TS 80004-13:2017, 3.1.2.6]
3.1.5
trilayer graphene
two-dimensional material consisting of three well-defined stacked graphene layers
Note 1 to entry: If the stacking registry is known, it can be specified separately, for example, as "twisted trilayer
graphene".
[SOURCE: ISO/TS 80004-13:2017, 3.1.2.9]
3.1.6
reduced graphene oxide
rGO
reduced oxygen content form of graphene oxide
Note 1 to entry: This can be produced by chemical, thermal, microwave, photo-chemical, photo-thermal or
microbial/bacterial methods or by exfoliating reduced graphite oxide.
Note 2 to entry: If graphene oxide was fully reduced, then graphene would be the product. However, in practice,
3 2
some oxygen containing functional groups will remain and not all sp bonds will return back to sp configuration.
Different reducing agents will lead to different carbon to oxygen ratios and different chemical compositions in reduced
graphene oxide.
Note 3 to entry: It can take the form of several morphological variations such as platelets and worm-like structures.
[SOURCE: ISO/TS 80004-13:2017, 3.1.2.14]
3.1.7
graphite
allotropic form of the element carbon, consisting of graphene layers stacked parallel to each
other in a three dimensional, crystalline, long-range order

– 10 – IEC TS 62607-6-14:2020  IEC:2020
Note 1 to entry: Adapted from the definition in the IUPAC Compendium of Chemical Terminology.
Note 2 to entry: There are two primary allotropic forms with different stacking arrangements: hexagonal and
rhombohedral.
[SOURCE: ISO/TS 80004-13:2017, 3.1.2.2]
3.1.8
blank detail specification
BDS
structured generic specification of the set of key control characteristics which are needed to
describe a specific nano-enabled product without assigning specific values and/or attributes
Note 1 to entry: The templates defined in a blank detail specification list the key control characteristics for the nano-
enabled material or product without assigning specific values to it.
Note 2 to entry: Examples of nano-enabled products are: nanomaterials, nanocomposites and nano-subassemblies.
Note 3 to entry: Blank detail specifications are intended to be used by industrial users to prepare their detail
specifications used in bilateral procurement contracts. A blank detail specification facilitates the comparison and
benchmarking of different materials. Furthermore, a standardized format makes procurement more efficient and more
error robust.
3.1.9
sectional blank detail specification
SBDS
specification based on a blank detail specification adapted for a subgroup of the nano-enabled
product
Note 1 to entry: In general, the sectional blank detail specification contains a subset of those key control
characteristics listed in the blank detail specification. In addition, sectional specific key control characteristics can
be added if they are not listed in the blank detail specification.
Note 2 to entry: The templates defined in the sectional blank detail specification can contain key control
characteristics with and without assigned values and attributes.
Note 3 to entry: The section can be defined by application, manufacturing method or general material properties.
3.1.10
detail specification
DS
specification based on a blank detail specification with assigned values and attributes
Note 1 to entry: The properties listed in the detail specification are usually a subset of the key control characteristics
listed in the relevant blank detail specification. The industrial partners define only those properties which are required
for the intended application.
Note 2 to entry: Detail specifications are defined by the industrial partners. SDOs will be involved only if there is a
general need for a detail specification in an industrial sector.
Note 3 to entry: The industrial partners can define additional key control characteristics if they are not listed in the
blank detail specification.
3.1.11
key control characteristic
KCC
key performance indicator
material property or intermediate product characteristic which can affect safety or compliance
with regulations, fit, function, performance, quality, reliability or subsequent processing of the
final product
Note 1 to entry: The measurement of a key control characteristic is described in a standardized measurement
procedure with known accuracy and precision.
Note 2 to entry: It is possible to define more than one measurement method for a key control characteristic if the
correlation of the results is well-defined and known.

3.2 Key control characteristics measured in accordance with this document
3.2.1
defect
local deviation from regularity in the crystal lattice of a 2D material
Note 1 to entry: Many different types of defect are present in the graphene material, including Stone-Wales defect,
single vacancy defect, multiple vacancy defect and interstitial defects. Broadly speaking, even doped heteroatoms
or foreign atoms can be regarded as one type of defect. It is worth noting that grain boundaries are not referred to
as defects here because the grain boundaries break the translational symmetry rather than the particular intrinsic
symmetry.
Note 2 to entry: Stone-Wales defect is generated by a pure reconstruction
...