IEC TS 62607-6-22:2022

Nanomanufacturing - Key control characteristics - Part 6-22: Graphene-based material - Ash content: Incineration

IEC TS 62607-6-22:2022 establishes a standardized method to determine the key control characteristic
ash content  of powder and dispersion of graphene-based material by
incineration.  The ash content is derived by residue obtained after incineration under the operating conditions specified in this document, being divided by the mass of the dried test portion.
The method is applicable for graphene, graphene oxide and reduced graphene oxide in forms of both dry powder and dispersion. This document can be used as reference for graphite oxide and other modified graphene.
Typical application areas of this method are research, manufacturer and downstream user to guide material processing and quality control.

General Information

• Status: Published
• Publication Date: 03-Nov-2022
• ICS: 07.120 - Nanotechnologies
• Technical Committee: TC 113 - Nanotechnology for electrotechnical products and systems
• Drafting Committee: WG 8 - TC 113/WG 8
• Current Stage: PPUB - Publication issued
• Start Date: 05-Dec-2022
• Completion Date: 04-Nov-2022

Standards Content (Sample)

IEC TS 62607-6-22
®

Edition 1.0 2022-11
TECHNICAL
SPECIFICATION

colour
inside


Nanomanufacturing – Key control characteristics –
Part 6-22: Graphene-based material – Ash content: incineration
IEC TS 62607-6-22:2022-11(en)

---------------------- Page: 1 ----------------------
THIS PUBLICATION IS COPYRIGHT PROTECTED
Copyright © 2022 IEC, Geneva, Switzerland

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 Secretariat 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 IEC Products & Services Portal - products.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews. With a subscription you will always have
committee, …). It also gives information on projects, replaced access to up to date content tailored to your needs.
and withdrawn publications.

Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
The world's leading online dictionary on electrotechnology,
Stay up to date on all new IEC publications. Just Published
containing more than 22 300 terminological entries in English
details all new publications released. Available online and once
and French, with equivalent terms in 19 additional languages.
a month by email.
Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc

If you wish to give us your feedback on this publication or need
further assistance, please contact the Customer Service
Centre: [e-mail].

---------------------- Page: 2 ----------------------
IEC TS 62607-6-22

®


Edition 1.0 2022-11




TECHNICAL



SPECIFICATION








colour

inside










Nanomanufacturing – Key control characteristics –

Part 6-22: Graphene-based material – Ash content: incineration


























INTERNATIONAL

ELECTROTECHNICAL


COMMISSION





ICS 07.120 ISBN 978-2-8322-6003-6




  Warning! Make sure that you obtained this publication from an authorized distributor.


® Registered trademark of the International Electrotechnical Commission

---------------------- Page: 3 ----------------------
– 2 – IEC TS 62607-6-22:2022  IEC 2022
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms, definitions, symbols and abbreviated terms . 7
3.1 General terms . 7
3.2 Key control characteristics measured in accordance with this document . 8
4 General . 9
4.1 Measurement principle . 9
4.1.1 Incineration principle . 9
4.1.2 Operation principle of this method . 9
4.2 Sample preparation method . 10
4.3 Description of measurement equipment . 10
4.4 Supporting materials . 11
4.5 Ambient conditions during measurement . 11
5 Measurement procedure . 11
5.1 Pre-treatment of sample . 11
5.1.1 Powder . 11
5.1.2 Dispersion . 12
5.2 Preparation of the crucible . 12
5.3 Incineration of sample . 12
5.3.1 Graphene and rGO . 12
5.3.2 GO and graphite oxide . 12
5.4 Weighing. 13
5.5 Completion of ashing . 13
6 Data analysis . 13
6.1 Ash content . 13
6.2 Repeatability . 13
7 Results to be reported . 13
7.1 General . 13
7.2 Product or sample identification . 14
7.3 Test conditions . 14
7.4 Test results . 14
Annex A (informative) Format of the test report . 15
Annex B (informative) Worked examples . 17
B.1 rGO powder prepared by thermal exfoliation of graphite oxide: sample 1 . 17
B.2 rGO powder prepared by thermal exfoliation of graphite oxide: sample 2 . 18
B.3 Graphene powder prepared by liquid phase exfoliation: sample 3 . 19
B.4 GO dispersion: sample 4 . 19
B.5 Graphite oxide powder: sample 5 . 20
Bibliography . 22

Figure 1 – TG-DSC of graphite oxide and rGO in air with 2 °C/min heating speed . 10
Figure B.1 – Press and shape the sample 1 powder into a cylindrical pellet . 17
Figure B.2 – Incineration of sample 1 . 17

---------------------- Page: 4 ----------------------
IEC TS 62607-6-22:2022  IEC 2022 – 3 –
Figure B.3 – Pre-treatment of sample 2 . 18
Figure B.4 – Sample 4 dispersion becomes GO film after drying . 19

Table A.1 – Product identification (in accordance with the relevant blank detail
specification) . 15
Table A.2 – General material description (in accordance with the relevant blank detail
specification) . 15
Table A.3 – Measurement related information and results . 15
Table A.4 – Measurement results . 16
Table B.1 – Measurement results of sample 1 . 18
Table B.2 – Measurement results of sample 2 . 18
Table B.3 – Measurement results of sample 3 . 19
Table B.4 – Measurement results of sample 4 . 20
Table B.5 – Measurement results of sample 5 . 21

---------------------- Page: 5 ----------------------
– 4 – IEC TS 62607-6-22:2022  IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

NANOMANUFACTURING – KEY CONTROL CHARACTERISTICS –

Part 6-22: Graphene-based material – Ash content: incineration

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.
IEC TS 62607-6-22 has been prepared by IEC technical committee 113: Nanotechnology for
electrotechnical products and systems. It is a Technical Specification.
The text of this Technical Specification is based on the following documents:
Draft Report on voting
113/704/DTS 113/681/RVDTS

Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this Technical Specification is English.

---------------------- Page: 6 ----------------------
IEC TS 62607-6-22:2022  IEC 2022 – 5 –
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement,
available at www.iec.ch/members_experts/refdocs. The main document types developed by
IEC are described in greater detail at www.iec.ch/publications.
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 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 document 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.

---------------------- Page: 7 ----------------------
– 6 – IEC TS 62607-6-22:2022  IEC 2022
INTRODUCTION
Impurity, which is inevitable because of the production process, often has significant influence
on the performance of graphene in energy conversion and storage, electronics, composites
and catalysis, etc. The ash content can quickly provide an indication of impurity to some
extent.
Determination of ash content of graphene is essential for manufacturers to perform quality
control. It is also important for users to choose suitable product.
Incineration, the most common method of testing ash content, is a low cost, good repeatable
and easy to operate method. Some unique properties of graphene-based material, such as
ultra-low bulk density, relative high oxygen content and thermal exfoliation, make it impossible
to follow existing incineration standards to determine the ash content of graphene-based
material correctly. With the development of the graphene industry, it is important to establish
a specific standard method for graphene to determine the ash content correctly. In this
method, the two key objectives are to increase the bulk density of ultra-low density reduced
graphene oxide through press or impregnation and to avoid instant exfoliation of high oxygen
content graphene oxide through low-speed heating during heating at 130 °C to 200 °C.
This document introduces a reliable method for determining the ash content of graphene with
incineration. This document can be used as the reference for other carbonaceous materials,
such as single-walled and multi-walled carbon nanotubes.

---------------------- Page: 8 ----------------------
IEC TS 62607-6-22:2022  IEC 2022 – 7 –
NANOMANUFACTURING – KEY CONTROL CHARACTERISTICS –

Part 6-22: Graphene-based material – Ash content: incineration



1 Scope
This part of IEC TS 62607 establishes a standardized method to determine the key control
characteristic
• ash content
of powder and dispersion of graphene-based material by
• incineration.
The ash content is derived by residue obtained after incineration under the operating
conditions specified in this document, being divided by the mass of the dried test portion.
• The method is applicable for graphene, graphene oxide and reduced graphene oxide in
forms of both dry powder and dispersion. This document can be used as reference for
graphite oxide and other modified graphene.
• Typical application areas of this method are research, manufacturer and downstream user
to guide material processing and quality control.
2 Normative references
There are no normative references in this document.
3 Terms, definitions, symbols and abbreviated terms
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
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-layer 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]

---------------------- Page: 9 ----------------------
– 8 – IEC TS 62607-6-22:2022  IEC 2022
3.1.2
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.
3.1.3
reduced graphene oxide
rGO
reduced oxygen content form of graphene oxide
[SOURCE: ISO/TS 80004-13:2017 [1], 3.1.2.14]
3.1.4
graphene oxide
GO
chemically modified graphene prepared by oxidation and exfoliation of graphite, causing
extensive oxidative modification of the basal plane
[SOURCE: ISO/TS 80004-13:2017. 3.1.2.13]
3.1.5
graphite oxide
chemically modified graphite prepared by extensive oxidative modification of the basal planes
Note 1 to entry: The structure and properties of graphite oxide depend on the degree of oxidation and the
particular synthesis method.
[SOURCE: ISO/TS 80004-13:2017, 3.1.2.12]
3.2 Key control characteristics measured in accordance with this document
3.2.1
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.
3.2.2
ash
residue obtained after incineration at a temperature of 650 °C under the operating conditions
specified in this document, divided by the mass of the test portion
Note 1 to entry: The content of ash is usually expressed as a percentage.

---------------------- Page: 10 ----------------------
IEC TS 62607-6-22:2022  IEC 2022 – 9 –
3.2.3
thermal gravimetry
TG
method in which the change in mass of a sample is measured as a function of temperature
while the sample is subjected to a controlled temperature programme
[SOURCE: ISO 80004-13:2017, 3.3.2.5]
3.2.4
differential scanning calorimetry
DSC
method in which the difference in energy inputs into a substance and a reference material is
measured as a function of temperature while the substance and reference material are
subjected to a controlled temperature programme
[SOURCE: ISO/TS 80004-6:2021, 6.2.1]
3.2.5
TG-DSC
combined technology of TG and DSC in which TG and DSC data of tested sample are
obtained simultaneously
4 General
4.1 Measurement principle
4.1.1 Incineration principle
A test portion is pre-treated, dried and then incinerated at a controlled and programmed
temperature in air, until complete disappearance of the carbon in the residue. After cooling to
room temperature, the mass of the residue is determined.
4.1.2 Operation principle of this method
4.1.2.1 GO and graphite oxide
a) GO and graphite oxide have high content of oxygen functional groups. These oxygen
functional groups can be decomposed at 130 °C to 200 °C to produce gas and heat, as
shown in TG-DSC of graphite oxide (Figure 1a). Decomposition will happen at both outer
surface and interior of sample at the same time.
1) On one hand, the produced gas increases the pressure between graphene sheets
inside the sample. When this pressure is larger than the total of Van der Waals force
among graphene sheets and external pressure, the sample will be exfoliated instantly,
expanding will happen and lead to a splash of sample.
2) On the other hand, the produced heat will accelerate the decomposition itself, which
will result in more gas and heat.
3) Therefore, slow heating speed is needed during incineration at 130 °C to 200 °C to
limit the decomposition speed. And to bring gas and heat out in a timely manner, the
furnace should be with an appropriate air ventilation during incineration.
b) GO and graphite oxide will begin to be incinerated at around 400 °C. The incineration
begins at the outer surface of sample and cannot lead to an increased pressure between
graphene sheets, therefore the sample will not expand. Therefore, fast heating speed is
needed during incineration at 200 °C to 650 °C to complete the oxidation.

---------------------- Page: 11 ----------------------
– 10 – IEC TS 62607-6-22:2022  IEC 2022
4.1.2.2 Graphene and rGO
Graphene and rGO have been exfoliated and reduced. Decomposition at 130 °C to 200 °C
produces very little gas and heat, as shown in TG-DSC of rGO (Figure 1b), and the produced
gas and heat can be expelled in a timely manner, passing through the exfoliated graphene
sheet. So, the fast heating speed during the whole incineration will not result in expansion of
sample. Therefore, incineration of graphene and rGO can be conducted at a very fast heating
speed directly from room temperature to 650 °C.


a) graphite oxide b) rGO
Figure 1 – TG-DSC of graphite oxide and rGO in air with 2 °C/min heating speed
4.2 Sample preparation method
The general analysis sample shall be mixed carefully before preparation.
4.3 Description of measurement equipment
Use laboratory apparatus and, in particular, the following.
4.3.1 Beaker.
4.3.2 Petri dishes.
4.3.3 Tablet press machine.
4.3.4 Square crucible, of inert material, such as porcelain, silica, platinum or any other
material unaffected under the test conditions with a square flat base.
The size shall be 30 mm (W) × 60 mm (L) × 15 mm (H), of such a size that the sample loading
2
does not exceed 0,08 g/cm for graphite oxide and graphene oxide.
4.3.5 Desiccator and desiccant.
A desiccator with appropriate desiccant is required to prevent absorption of moisture from
atmosphere by the test sample and ash.
4.3.6 Furnace, of muffle type or tube type.
The furnace shall be capable of providing a zone of uniform heat at the temperature required
and reaching these temperatures within the specified times.
The air ventilation rate through the furnace shall be such as to give at least two air exchanges
per hour.

---------------------- Page: 12 ----------------------
IEC TS 62607-6-22:2022  IEC 2022 – 11 –
4.3.7 Analytical balance, capable of reading to the nearest 0,1 mg.
4.3.8 Electric thermostatic drying oven.
4.4 Supporting materials
Use only reagents of recognized analytical grade, unless otherwise specified.
1
4.4.1 Water, complying with at least grade 3 in accordance with ISO 3696 [2] .
4.4.2 Ethanol, analytical reagent.
4.5 Ambient conditions during measurement
The measurements can be performed under regular laboratory conditions without precise
temperature and humidity control.
5 Measurement procedure
5.1 Pre-treatment of sample
5.1.1 Powder
5.1.1.1 GO and graphite oxide powder
Place the GO or graphite oxide powder sample in the electric thermostatic drying oven and
heat at (105 ± 5) °C to remove the water completely. Cool to room temperature in the
desiccator.
5.1.1.2 rGO and graphene powder
5.1.1.2.1 rGO and graphene powder prepared by thermal exfoliation
a) Place about 0,2 g to 0,3 g of the rGO powder sample into the mould of the tablet press
machine, then press and shape the sample into a cylindrical pellet by applying a pressure
of about 2 MPa. Place the cylindrical pellet in the electric thermostatic drying oven and
heat at (105 ± 5) °C to remove the moisture completely. Cool to room temperature in the
desiccator.
b) Some rGO powder cannot be pressed and shaped into a cylindrical pellet. For these kinds
of sample, the pre-treatment is to place about 0,6 g of sample into a clean beaker, add
about 20 mL water and then use a glass rod to well mix the sample with water. If the
sample is too hydrophobic to disperse in water, ethanol can be added to disperse well.
Place the beaker in the electric thermostatic drying oven and heat at (105 ± 5) °C to
remove the water completely. Cool to room temperature in the desiccator.
5.1.1.2.2 rGO and graphene powder prepared by other methods
Place these kinds of rGO or graphene powder sample in the electric thermostatic drying oven
and heat at (105 ± 5) °C to remove the moisture completely. Cool to room temperature in the
desiccator.

—————————
1
Numbers in square brackets refer to the Bibliography.

---------------------- Page: 13 ----------------------
– 12 – IEC TS 62607-6-22:2022  IEC 2022
5.1.2 Dispersion
Place a certain amount of the dispersion containing 0,5 g to 0,6 g of the solid sample into a
Petri dish and then place the Petri dishes in the electric thermostatic drying oven and heat at
(105 ± 5) °C for water dispersion or (130 ± 5) °C for N-Methylpyrrolidone dispersion to remove
the solvent completely. Cool to room temperature in the desiccator. After pre-treatment,
graphene oxide dispersion (GO dispersion) becomes graphene oxide film (GO film) and
graphene or rGO dispersion becomes graphene or rGO bulk.
The thickness of dried film will affect the thermal behaviour of the film. To control the
thickness of film, it is recommended that the solid content of GO dispersion added to each
Petri dish with a diameter of 10 cm is not more than 1 g.
5.2 Preparation of the crucible
Clean the crucible with tap water and then with distilled water at least three times.
Place the as-prepared crucible in the furnace and heat for at least 1 h at (850 ± 25) °C. Allow
to cool to room temperature in the desiccator and then weigh to nearest 0,000 1 g and record
the mass as m .
1
NOTE Several crucibles can be handled at the same time.
5.3 Incineration of sample
5.3.1 Graphene and rGO
Weigh rapidly, to the nearest 0,000 1 g, 0,5 g of the pre-treated sample at the bottom of the
as-prepared crucible and spread in an even layer over the bottom surface, record the mass of
crucible as m and the mass of crucible plus the test portion as m .
1 2
Place the crucible in a room temperature furnace with air ventilation and heat the test portion
in accordance with the following procedure.
• Raise the furnace temperature evenly from room temperature to (650±10) °C over a period
of 30 minutes.
• Maintain the temperature at (650±10) °C for 120 minutes to complete incineration.
5.3.2 GO and graphite oxide
Weigh rapidly, to the nearest 0,000 1 g, 0,5 g of the pre-treated sample at the bottom of the
as-prepared crucible and spread in an even layer over the bottom surface. Record the mass
of crucible as m and the mass of crucible plus the test portion as m .
1 2
Place the
...