NANOMATERIALS
CHEMISTRY FOR ENGINEERS 2023
Nanoscience & Nanotechnology
Nanoscience is the study of the materials of nanoscale.
Materials of nanoscale of 1 – 100 nm.
Nanotechnology is the application of nanoscience
Design, characterization, production and application, structures, devices
and system of nanoscale materials.
Synthesis, manipulation, design and application of functional system or
materials at the nanoscale.
Understanding and control of materials on the atomic or molecular scale
(National Geography, 2022)
https://www.youtube.com/watch?v=R0ZZa9YlsjE
Nanomaterials
Nanoparticles, NPs
Tiny materials having minimum sizes ranging from 1
to 100 nm
Chemical substances or materials composed of very
small particles of different shapes and sizes no
larger than 100 nanometers, or about 1000 times less
than the thickness of human hair.
Classes of NPs
according to occurrences
Natural NPs
Found in nature
𝐅𝐞𝐎, 𝐅𝐞𝟐 𝐎𝟑 , 𝐅𝐞𝐒, 𝐀𝐠, 𝐀𝐮 produced from
ocean spray, forest fire, dust
storms, volcanic ash, and
biological particles like fungi and
virus.
By Product NPs
Industrially or biological produced
together with the major or principal
product particularly during combustion
reactions.
https://www.twi-global.com/
Engineered NPs
Man-made NPs
Specially produced NPs through
engineering to perform for special
purpose.
Classes of NPs
according to composition
Organic-based NPs
sourced mainly from living things like
proteins aggregates,
lipid bodies, milk emulsions, or
complex organized
structures like viruses.
Inorganic-based NPs
composed of a metal element or nonmetal
element, or take the form of 𝐎𝟐− , 𝐎𝐇 𝟏− ,
chalcogenide like 𝐒 𝟐− , 𝐒𝐞𝟐−
and 𝐓𝐞𝟐− , or 𝐏𝐎𝟑−
𝟒 compounds.
Carbon-based NPs
composed mostly of 𝐂 like carbon
nanotubes, carbon nanofibers,
graphene sheets, graphene quantum
dots, graphene nanoribbons, and
graphene nanoparticles.
Composite-based NPs
• combined, hybrid, core-shell prepared
with other NPs or with larger, bulk type
materials.
Production of NPs
Top-down Approach
involves the breaking
down of large pieces of
material to generate the
required nanostructure
of nanomaterials.
Top-down Approach for NPs
Bottom-up Approach
The Bottom-up approach
involves assembling of single
atoms and molecules into
larger nanostructures of
nanomaterials.
Bottom-up approach for NPs
Synthesis of NPs
Chemical Vapor Deposition
The substrate is
exposed to one or more
volatile precursors,
which react and
decompose on the
substrate surface to
produce the desired thin
film deposit.
https://www.youtube.com/watch?app=desktop&v=9XKGVHPXXho
Precipitation Processes
or Co-precipitation Process
The simultaneous
precipitation of more than
one compound from a
solution
Sol-gel Process or
Chemical wet process
The molecular precursor is dissolved in
water or alcohol and converted to gel
by heating or hydrolysis or alcoholysis.
Aerosol Process
The aerosol is suspended in a liquid
which is heated to 𝟐𝟑𝟓𝒐 - 𝟑𝟎𝟎𝒐 C under
pressure and passed through orifice
to form aerosols.
Flame hydrolysis – an exothermic
combustion of the liquid phase,
followed by evaporation, oxidation,
and nucleation under high flame to
form subsequent solid nanomaterials
via coagulation, sintering, and
agglomeration.
Determinants in NPs Synthesis
Particle size
Chemical composition
Crystallinity
Shape
Temperature
pH
Concentration
Surface modification
Process control
Properties of NPs
Highly mobile in free state – ability to move freely or easily
High surface areas – ability to cover void surface area
Unusual phase transformation – ability to absorb or emit energy
Defect stabilization – ability to keep the structure by minimizing or avoid
imperfection
Surface strain – ability to reduce breaking the surface due to excessive force
applied.
Controlled aggregation – ability of material to form into clusters
Uses of NPs Environmental preservation
Drug delivery
Carbon Nanotubes
Sunscreen or UV protection
Morphing wing
Properties of CNTs, Carbon nanotubes
High thermal conductivity
High electrical conductivity
Ratio
Very elastic
High tensile strength
High flexible
Low thermal expansion coefficient
Good electron emitters
Uses of CNTs
Energy storage Thin-film electronics
Modeling device Coatings
Automotive parts Actuators
Boat hulls Electromagnetic shields
Sporting goods Water filters
Carbon nanotube baseball bat Nano-Ti𝐎𝟐 camouflage uniform
Antibacterial nanomaterial towels
Self-cleaning coating
Solar panels
Electronic circuits
Metal oxides NPs (𝐍iO, 𝐙𝐧𝐎, 𝐌𝐧𝐎𝟐 , 𝐅𝐞𝟐 𝐎𝟑 , 𝐓𝐢𝐎𝟐 , 𝐂𝐨𝟑 𝐎𝟒 NPs)
Properties of Metal Oxides NPs
Crystalline solids containing metal cations and oxide anions.
Reactive with 𝐇𝟐 𝐎 to form acids and bases, and forms salts.
UV absorption
Color absorption within visible region dichroism
Photoluminescence
Uses Catalyst – substance that speeds up or slows
down chemical reaction without itself
of going any permanent change.
Metal Oxides Adsorbent – substance that allows for other
substance to stay on its surface.
Superconductor – substance that have
superconductivity at very cold
temperature, no electrical
resistance, and does not allow
magnetic field penetration
Semiconductor – substance that have conductivity
between conductor and insulators
Ceramics – crystalline, glassy non-reactive substance
Antifungal agents – substance to prevent fungus
growth
Nanotechnology in the Philippines
Department of Science and Technology –
Philippine Council for Advanced Science and
Technology Research and Development
Semiconductor, IT, Energy, Agriculture,
Medicine, and Environmental Protection
Nanosilica-based Fertilizer to increase
germination and growth rate of tomatoes;
fruitect coating technology to boost shelf life
of high valued-fruits like mango and papaya;
nanoencapsulated plant growth regulators to
enhance germination and root development of
coffee, banana and cassava
REFERENCES
Austrian Academy of Sciences. (2022). Accessed on September 30, 2022 at
https://www.nanowerk.com/how_nanoparticles_are_made.php
Bhayarai, Sneha Mohan., Oluwafemi, Oluwatobi Samuel (2018). Nanothechnology: The Science of
the Invisisble.
Accessed on September 16, 2022 at https://www.sciencedirect.com/
Brown, Katherine B., Brown, Cristine Marie B., and Nepomuceno, Robert A. (2022).
Nanotechnology in the
Philippines: Status and Intellectual Property Rights Issues. Accessed on September 15,
2022 at
https://www.researchgate.net/
Khan, Ibrahim & Saeed, Khalid. (2019). Nanoparticles: Properties, applications and toxicities.
Accessed on
September 3, 2022 at https://www.sciencedirect.com/
Public Health (2007). Nanotechnology.
https://ec.europa.eu/health/scientific_committees/opinions_layman/en/nanotechnologies/l-
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