ISO TS 80004-6:2013
(Main)Nanotechnologies - Vocabulary - Part 6: Nano-object characterization
Nanotechnologies - Vocabulary - Part 6: Nano-object characterization
ISO/TS 80004-6:2013 lists terms and definitions relevant to the characterization of nano-objects.
Nanotechnologies - Vocabulaire - Partie 6: Caractérisation des nano-objets
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Standards Content (Sample)
TECHNICAL ISO/TS
SPECIFICATION 80004-6
First edition
2013-11-01
Nanotechnologies — Vocabulary —
Part 6:
Nano-object characterization
Nanotechnologies — Vocabulaire —
Partie 6: Caractérisation d’un nano-objet
Reference number
ISO/TS 80004-6:2013(E)
©
ISO 2013
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ISO/TS 80004-6:2013(E)
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ISO/TS 80004-6:2013(E)
Contents Page
Foreword .iv
Introduction .vi
1 Scope . 1
2 General terms . 1
3 Terms related to size and shape measurement . 3
3.1 Terms related to measurands for size and shape . 3
3.2 Terms related to scattering techniques . 4
3.3 Terms related to aerosol characterization . 5
3.4 Terms related to separation techniques . 6
3.5 Terms related to microscopy . 7
3.6 Terms related to surface area measurement .10
4 Terms related to chemical analysis .11
5 Terms related to measurement of other properties .15
5.1 Terms related to mass measurement .15
5.2 Terms related to crystallinity measurement .16
5.3 Terms related to charge measurement in suspensions .16
Annex A (informative) Index .18
Bibliography .23
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ISO/TS 80004-6:2013(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
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electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2. www.iso.org/directives
Attention is drawn to the possibility that some of the elements of this document may be the subject of
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For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers
to Trade (TBT) see the following URL: Foreword - Supplementary information
ISO/TS 80004-6 was prepared jointly by Technical Committee ISO/TC 229, Nanotechnologies and
Technical Committee IEC/TC 113, Nanotechnology standardization for electrical and electronic products
and systems. The draft was circulated for voting to the national bodies of both ISO and IEC.
Documents in the 80000 to 89999 range of reference numbers are developed by collaboration
between ISO and IEC.
ISO/TS 80004 consists of the following parts, under the general title Nanotechnologies — Vocabulary:
— Part 1: Core terms
— Part 3: Carbon nano-objects
— Part 4: Nanostructured materials
— Part 5: Nano/bio interface
— Part 6: Nano-object characterization
— Part 7: Diagnostics and therapeutics for healthcare
— Part 8: Nanomanufacturing processes
The following parts are under preparation:
1)
— Part 2: Nano-objects: Nanoparticle, nanofibre and nanoplate
— Part 9: Nano-enabled electrotechnical products and systems
— Part 10: Nano-enabled photonic components and systems
— Part 11: Nanolayer, nanocoating, nanofilm, and related terms
1) Revision of ISO/TS 27687:2008, Nanotechnologies — Terminology and definitions for nano-objects —
Nanoparticle, nanofibre and nanoplate.
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ISO/TS 80004-6:2013(E)
— Part 12: Quantum phenomena in nanotechnology
Graphene and other two dimensional materials will form the subject of a future Part 13.
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ISO/TS 80004-6:2013(E)
Introduction
Measurement and instrumentation techniques have effectively opened the door to modern
nanotechnology. Characterization is key to understanding the properties and function of all nano-objects.
Nano-object characterization involves interactions between people with different backgrounds and
from different fields. Those interested in nano-object characterization might, for example, be materials
scientists, biologists, chemists or physicists and might have a background that is primarily experimental
or theoretical. Those making use of the data extend beyond this group to include regulators and
toxicologists. To avoid any misunderstandings, and to facilitate both comparability and the reliable
exchange of information, it is essential to clarify the concepts, to establish the terms for use and to
establish their definitions.
The terms are classified under the following broad headings:
— Clause 2: General terms
— Clause 3: Terms related to size and shape measurement
— Clause 4: Terms related to chemical analysis
— Clause 5: Terms related to measurement of other properties
These headings are intended as guide only, as some techniques can determine more than one property.
Subclause 3.1 lists the overarching measurands that apply to the rest of Clause 3. Other measurands are
more technique specific and are placed in the text adjacent to the technique.
It should be noted that most techniques require analysis in a non-native state and involve sample
preparation, for example placing the nano-objects on a surface or placing it in a specific fluid or vacuum.
This could change the nature of the nano-objects.
The order of the techniques in this document should not be taken to indicate a preference and the
techniques listed in this document are not intended to be exhaustive. Equally, some of the techniques
listed in this document are more popular than others in their usage in analysing certain properties of
nano-objects. Table 1 lists alphabetically the main current techniques for nano-object characterization.
Table 1 — Alphabetical list of main current techniques for nano-object characterization
Property Current main techniques
Size atomic force microscopy (AFM), centrifugal liquid sedimentation (CLS), differential
mobility analysing system (DMAS), dynamic light scattering (DLS), scanning electron
microscopy (SEM), particle tracking analysis (PTA), transmission electron microscopy
(TEM)
Shape atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission
electron microscopy (TEM)
Surface area Brunauer-Emmett-Teller (BET) method
‘Surface’ chemistry secondary ion mass spectrometry (SIMS), X-ray photoelectron spectroscopy (XPS)
Chemistry of the inductively coupled plasma mass spectrometry (ICP-MS), nuclear magnetic resonance
‘bulk’ sample spectroscopy (NMR)
Charge in suspensions zeta potential
This document is intended to serve as a starting reference for the vocabulary that underpins measurement
and characterization efforts in the field of nanotechnologies.
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TECHNICAL SPECIFICATION ISO/TS 80004-6:2013(E)
Nanotechnologies — Vocabulary —
Part 6:
Nano-object characterization
1 Scope
This Technical Specification lists terms and definitions relevant to the characterization of nano-objects.
2 General terms
2.1
nanoscale
size range from approximately 1 nm to 100 nm
Note 1 to entry: Properties that are not extrapolations from a larger size will typically, but not exclusively, be
exhibited in this size range. For such properties the size limits are considered approximate.
Note 2 to entry: The lower limit in this definition (approximately 1 nm) is introduced to avoid single and small
groups of atoms from being designated as nano-objects (2.2) or elements of nanostructures, which might be
implied by the absence of a lower limit.
[SOURCE: ISO/TS 80004-1:2010, definition 2.1]
2.2
nano-object
material with one, two or three external dimensions in the nanoscale (2.1)
Note 1 to entry: Generic term for all discrete nanoscale objects.
[SOURCE: ISO/TS 80004-1:2010, definition 2.5]
2.3
nanoparticle
nano-object (2.2) with all three external dimensions in the nanoscale (2.1)
Note 1 to entry: If the lengths of the longest to the shortest axes of the nano-object differ significantly (typically
by more than three times), the terms nanofibre (2.6) or nanoplate (2.4) are intended to be used instead of the term
nanoparticle.
[SOURCE: ISO/TS 27687:2008, definition 4.1]
2.4
nanoplate
nano-object (2.2) with one external dimension in the nanoscale (2.1) and the two other external
dimensions significantly larger
Note 1 to entry: The smallest external dimension is the thickness of the nanoplate.
Note 2 to entry: The two significantly larger dimensions are considered to differ from the nanoscale dimension
by more than three times.
Note 3 to entry: The larger external dimensions are not necessarily in the nanoscale.
[SOURCE: ISO/TS 27687:2008, definition 4.2]
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ISO/TS 80004-6:2013(E)
2.5
nanorod
solid nanofibre (2.6)
[SOURCE: ISO/TS 27687:2008, definition 4.5]
2.6
nanofibre
nano-object (2.2) with two similar external dimensions in the nanoscale (2.1) and the third dimension
significantly larger
Note 1 to entry: A nanofibre can be flexible or rigid.
Note 2 to entry: The two similar external dimensions are considered to differ in size by less than three times and
the significantly larger external dimension is considered to differ from the other two by more than three times.
Note 3 to entry: The largest external dimension is not necessarily in the nanoscale.
[SOURCE: ISO/TS 27687:2008, definition 4.3]
2.7
nanotube
hollow nanofibre (2.6)
[SOURCE: ISO/TS 27687:2008, definition 4.4]
2.8
quantum dot
crystalline nanoparticle (2.3) that exhibits size-dependent properties due to quantum confinement
effects on the electronic states
[SOURCE: ISO/TS 27687:2008, definition 4.7]
2.9
particle
minute piece of matter with defined physical boundaries
Note 1 to entry: A physical boundary can also be described as an interface.
Note 2 to entry: A particle can move as a unit.
Note 3 to entry: This general particle definition applies to nano-objects (2.2).
[SOURCE: ISO 14644-6:2007, definition 2.102 and ISO/TS 27687:2008, definition 3.1]
2.10
agglomerate
collection of weakly bound particles (2.9) or aggregates (2.11) or mixtures of the two where the resulting
external surface area is similar to the sum of the surface areas of the individual components
Note 1 to entry: The forces holding an agglomerate together are weak forces, for example van der Waals forces, or
simple physical entanglement.
Note 2 to entry: Agglomerates are also termed secondary particles and the original source particles are termed
primary particles.
[SOURCE: ISO/TS 27687:2008, definition 3.2]
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ISO/TS 80004-6:2013(E)
2.11
aggregate
particle (2.9) comprising strongly bonded or fused particles where the resulting external surface area
may be significantly smaller than the sum of calculated surface areas of the individual components
Note 1 to entry: The forces holding an aggregate together are strong forces, for example covalent bonds, or those
resulting from sintering or complex physical entanglement.
Note 2 to entry: Aggregates are also termed secondary particles and the original source particles are termed
primary particles.
[SOURCE: ISO/TS 27687:2008, definition 3.3]
2.12
aerosol
system of solid or liquid particles (2.9) suspended in gas
[SOURCE: ISO 15900:2009, definition 2.1]
2.13
suspension
heterogeneous mixture of materials comprising a liquid and a finely dispersed solid material
[SOURCE: ISO 4618:—, definition 2.243]
3 Terms related to size and shape measurement
3.1 Terms related to measurands for size and shape
3.1.1
particle size
linear dimension of a particle (2.9) determined by a specified measurement method and under specified
measurement conditions
[SOURCE: ISO 26824:2013, definition 1.5]
Note 1 to entry: Different methods of analysis are based on the measurement of different physical properties.
Independent of the particle property actually measured, the particle size can be reported as a linear dimension,
e.g. as the equivalent spherical diameter.
3.1.2
particle size distribution
distribution of particles (2.9) as a function of particle size (3.1.1)
[SOURCE: ISO 14644-1:1999, definition 2.2.4, modified]
Note 1 to entry: Particle size distribution may be expressed as cumulative distribution or a distribution density
(distribution of the fraction of material in a size class, divided by the width of that class).
3.1.3
particle shape
external geometric form of a particle (2.9)
[SOURCE: ISO 3252:1999]
3.1.4
aspect ratio
ratio of length of a particle (2.9) to its width
[SOURCE: ISO 14966:2002, definition 2.8]
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ISO/TS 80004-6:2013(E)
3.1.5
equivalent diameter
diameter of a sphere that produces a response by a given particle-sizing method, that is equivalent to the
response produced by the particle (2.9) being measured
Note 1 to entry: The physical property to which the equivalent diameter refers is indicated using a suitable
subscript (see ISO 9276-1:1998).
Note 2 to entry: For discrete-particle-counting, light-scattering instruments, an equivalent optical diameter is used.
Note 3 to entry: Other material constants like density of the particle are used for the calculation of the equivalent
diameter like Stokes diameter or sedimentation equivalent diameter. The material constants, used for the
calculation, should be reported additionally.
Note 4 to entry: For inertial instruments, the aerodynamic diameter is used. Aerodynamic diameter is the
−3
diameter of a sphere of density 1 000 kg m that has the same settling velocity as the irregular particle.
[SOURCE: ISO/TS 27687:2008, A.3.3, modified]
3.2 Terms related to scattering techniques
3.2.1
radius of gyration
measure of the distribution of mass about a chosen axis, given as the square root of the moment of
inertia about that axis divided by the mass
[SOURCE: ISO 14695:2003, definition 3.4]
Note 1 to entry: For nano-object (2.2) characterization, physical methods that measure radius of gyration to
determine particle size (3.1.1) include static light scattering, small angle neutron scattering (3.2.2) and small angle
X-ray scattering (3.2.4).
3.2.2
small angle neutron scattering
SANS
method in which a beam of neutrons is scattered from a sample and the scattered neutron intensity is
measured for small angle deflection
Note 1 to entry: The scattering angle is usually between 0,5° and 10° in order to study the structure of a material
on the length scale of 1 nm to 100 nm. The method provides information on the sizes of the particles (2.9) and to
a limited extent the shapes of the particles dispersed in homogeneous medium.
3.2.3
neutron diffraction
application of elastic neutron scattering for the determination of the atomic or magnetic structure of matter
Note 1 to entry: The neutrons emerging from the experiment have approximately the same energy as the incident
neutrons. A diffraction pattern is formed that provides information on the structure of the material.
3.2.4
small angle X-ray scattering
SAXS
method in which the elastically scattered intensity of X-rays is measured for small-angle deflections
Note 1 to entry: The angular scattering is usually measured within the range 0,1° to 10°. This provides structural
information on macromolecules as well as periodicity on length scales typically larger than 5 nm and less than
200 nm for ordered or partially ordered systems.
[SOURCE: ISO 18115-1, definition 4.18]
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ISO/TS 80004-6:2013(E)
3.2.5
light scattering
change in propagation of light at the interface of two media having different optical properties
[SOURCE: ISO 13320:2009, definition 3.1.17]
3.2.6
hydrodynamic diameter
equivalent diameter (3.1.5) of a particle (2.9) in a liquid having the same diffusion coefficient as the real
particle in that liquid
3.2.7
dynamic light scattering
DLS
photon correlation spectroscopy
PCS
quasi-elastic light scattering
QELS
method in which particles (2.9) undergoing Brownian motion in a liquid suspension (2.13) are illuminated
by a laser and the change in intensity of the scattered light is used to determine particle size (3.1.1)
Note 1 to entry: Analysis of the time-dependent intensity of the scattered light can yield the translational diffusion
coefficient and hence the particle size as the hydrodynamic diameter (3.2.6) via the Stokes–Einstein relationship.
Note 2 to entry: The analysis is applicable to nanoparticles (2.3) as the size of particles detected is typically in the
range 1 nm to 6000 nm. The upper limit is due to limited Brownian motion and sedimentation.
3.2.8
nanoparticle tracking analysis
NTA
particle tracking analysis
PTA
method where particles (2.9) undergoing Brownian motion in a liquid suspension (2.13) are illuminated
by a laser and the change in position of individual particles is used to determine particle size (3.1.1)
Note 1 to entry: Analysis of the time-dependent position of individual particles by means of scattered light can
yield the translational diffusion coefficient and hence the particle size as the hydrodynamic diameter (3.2.6) using
the Stokes–Einstein relationship
Note 2 to entry: The analysis is applicable to nanoparticles (2.3) as the size of particles detected is typically in the
range 10 nm to 2000 nm. The lower limit requires particles with high refractive index and the upper limit is due
to limited Brownian motion and sedimentation.
3.3 Terms related to aerosol characterization
3.3.1
condensation particle counter
CPC
instrument that measures the particle (2.9) number concentration of an aerosol (2.12)
Note 1 to entry: The sizes of particles detected are usually smaller than several hundred nanometres and larger
than a few nanometres.
Note 2 to entry: A CPC is one possible detector suitable for use with a differential electrical mobility classifier
(DEMC) (3.3.2).
Note 3 to entry: In some cases, a condensation particle counter may be called a condensation nucleus counter (CNC).
[SOURCE: ISO 15900:2009, definition 2.5]
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ISO/TS 80004-6:2013(E)
3.3.2
differential electrical mobility classifier
DEMC
classifier that is able to select aerosol (2.12)particles (2.9) according to their electrical mobility and pass
them to its exit
Note 1 to entry: A DEMC classifies aerosol particles by balancing the electrical force on each particle with its
aerodynamic drag force in an electrical field. Classified particles are in a narrow range of electrical mobility
determined by the operating conditions and physical dimensions of the DEMC, while they can have different sizes
due to difference in the number of charges that they have.
[SOURCE: ISO 15900:2009, definition 2.7]
3.3.3
differential mobility analysing system
DMAS
system to measure the size distribution of submicrometre aerosol (2.12)particles (2.9) consisting of a DEMC
(3.3.2), flow meters, a particle detector, interconnecting plumbing, a computer and suitable software
[SOURCE: ISO 15900:2009, definition 2.8]
3.3.4
Faraday-cup aerosol electrometer
FCAE
system designed for the measurement of electrical charges carried by aerosol (2.12)particles (2.9)
Note 1 to entry: A Faraday-cup aerosol electrometer consists of an electrically conducting and electrically grounded
cup as a guard to cover the sensing element that includes aerosol filtering media to capture charged aerosol particles,
an electrical connection between the sensing element and an electrometer circuit, and a flow meter.
[SOURCE: ISO 15900:2009, definition 2.12, modified]
3.4 Terms related to separation techniques
3.4.1
field flow fractionation
FFF
separation technique where a field is applied to a liquid suspension (2.13) passing along a narrow channel
in order to cause separation of the particles (2.9) present in the liquid, dependent on their differing
mobility under the force exerted by the field
Note 1 to entry: The field can be, for example, gravitational, centrifugal, a liquid flow, electrical or magnetic.
Note 2 to entry: Using a suitable detector after or during separation allows determination of the size and size
distribution of nano-objects (2.2).
3.4.2
centrifugal liquid sedimentation
CLS
differential centrifugal sedimentation
DCS
method in which a sample is separated based on size and density using a rotating disc filled with a fluid
containing a density gradient
Note 1 to entry: Depending on the density of the particles (2.9), the technique can measure particle size (3.1.1) and
particle size distribution (3.1.2) between 2 nm and 10 µm and can resolve particles differing in size by less than 2 %.
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ISO/TS 80004-6:2013(E)
3.4.3
size-exclusion chromatography
SEC
liquid chromatographic technique in which the separation is based on the hydrodynamic volume of
molecules eluting in a column packed with porous non-adsorbing material having pore dimensions that
are similar in size to the molecules being separated
[SOURCE: ISO 16014-1:2012, definition 3.1]
Note 1 to entry: SEC can be coupled with a detector, for example dynamic light scattering (DLS) (3.2.7), for
determination of the size and size distribution of the eluting species.
3.4.4
electrical zone sensing
Coulter counter
method for counting and sizing particles (2.9) in electrolytes by measuring a drop in electrical current
as a particle passes through an aperture between two chambers
Note 1 to entry: The drop in current is proportional to the particle volume.
Note 2 to entry: The particles are driven through the aperture by pressure or an electric field.
Note 3 to entry: The aperture can be nanoscale (2.1) in size allowing the sizing of individual nano-objects (2.2).
3.5 Terms related to microscopy
The following are the definitions of microscopy methods and related terms. In the list below, note
that the final “M” in the acronyms, given as “microscopy”, may also mean “microscope” depending
on the context. For the definition relating to the microscope, replace the word “method” by the word
“instrument” where that appears.
3.5.1
scanning probe microscopy
SPM
method of imaging surfaces by mechanically scanning a probe over the surface under study, in which the
concomitant response of a detector is measured
[SOURCE: ISO 18115-2, definition 4.31]
Note 1 to entry: This generic term encompasses many methods including atomic force microscopy (AFM) (3.5.2),
scanning near field optical microscopy (SNOM) (3.5.4), scanning ion conductance microscopy (SICM) and scanning
tunnelling microscopy (STM) (3.5.3).
Note 2 to entry: The resolution varies from that of STM, where individual atoms can be resolved, to scanning
thermal microscopy (SThM) in which the resolution is generally limited to around 1 μm.
3.5.2
atomic force microscopy
AFM
scanning force microscopy (deprecated)
SFM (deprecated)
method for imaging surfaces by mechanically scanning their surface contours, in which the deflection of
a sharp tip sensing the surface forces, mounted on a compliant cantilever, is monitored
[SOURCE: ISO 18115-2, definition 4.3]
Note 1 to entry: AFM can provide a quantitative height image of both insulating and conducting surfaces.
Note 2 to entry: Some AFM instruments move the sample in the x-, y- and z-directions while keeping the tip
position constant and others move the tip while keeping the sample position constant.
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ISO/TS 80004-6:2013(E)
Note 3 to entry: AFM can be conducted in vacuum, a liquid, a controlled atmosphere or air. Atomic resolution may
be attainable with suitable samples, with sharp tips and by using an appropriate imaging mode.
Note 4 to entry: Many types of force can be measured, such as the normal forces or the lateral, friction or shear
force. When the latter is measured, the technique is referred to as lateral, frictional or shear force microscopy.
This generic term encompasses all of these types of force microscopy.
Note 5 to entry: AFMs can be used to measure surface normal forces at individual points in the pixel array
used for imaging.
Note 6 to entry: For typical AFM tips with radii < 100 nm, the normal force should be less than about 0,1 μN,
depending on the sample material, or irreversible surface deformation and excessive tip wear occurs.
3.5.3
scanning tunnelling microscopy
STM
SPM (3.5.1) mode for imaging conductive surfaces by mechanically scanning a sharp, voltage-biased,
conducting probe tip over their surface, in which the data of the tunnelling current and the tip-surface
separation are used in generating the image
Note 1 to entry: STM can be conducted in vacuum, a liquid or air. Atomic resolution can be achieved with suitable
samples and sharp probes and can, with ideal samples, provide localized bonding information around surface atoms.
Note 2 to entry: Images can be formed from the height data at a constant tunnelling current or the tunnelling
current at a constant height or other modes at defined relative potentials of the tip and sample.
Note 3 to entry: STM can be used to map the densities of states at surfaces or, in ideal cases, around individual
atoms. The surface images can differ significantly, depending on the tip bias, even for the same topography.
[SOURCE: ISO 18115-2, definition 4.35]
3.5.4
near-field scanning optical microscopy
NSOM
scanning near-field op
...
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