Nanomaterials Terms

The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom.

The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom.

Richard Feynman, 1959

Plenty of Room at the Bottom

title of Richard Feynman’s talk

Father of Nanotechnology

Richard Feynman

Who first used the word nanotechnology?

Norio Taniguchi, 1974

nanos

dwarf

teknologia

systematic treatment of an art, craft or technique

nanometer (nm)

billionth of a meter, 10^-9 meters

Nanomaterial

having at least one dimension of a material stands at the nanoscale, between 1 to 100nm

Nanotechnology

involves imaging, measuring, modeling, and manipulating matter at the nanoscale

Nanoparticles

particles having sizes in the nanoscale, 1 to 100nm

Nature

best manufacturer of nanomaterials and nano-structures

Man-made

Incidental and Engineered Nanomaterials

Incidental Nanomaterials

generated as unintentional by-products of combustion processes

Engineered Nanomaterials

intentionally produced and designed with physico-chemical properties for a specific purpose or reason

Inorganic Nanoparticles

quantum dots, nanographene, carbon nanotubes, silica, gold, magnetic nanoparticles

Organic Nanoparticles

dendrimers, polymeric micelles, liposomes, polymeric nanoparticles

2D Nanomaterials

two dimensions still remain large and only one dimension is reduced to the nanoscale

example of 2D nanomaterial

Graphene, Nanosheets

1D Nanomaterials

only one dimension is large while the two other dimensions are at the nanoscale

example of 1D nanomaterial

Nanowires, Nanotubes

0D Nanomaterials

all three dimensions are at the nanoscale

example of 0D nanomaterials

Quantum Dots, Nanoparticles

Approaches to Nanomaterial Synthesis

Top-down and Bottom-up

Top-down Approach

modifying bulk material to required size and shape

Top-down / Mechanical Physical Processing

uses the milling process to reduce size of the material but restrains the full control of particle size

example of top-down approach

production of integrated circuits by etching, production of metallic and ceramic materials

Bottom-up Approach

assembling atoms or molecules to required size and shape

Bottom-up / Chemo-Physical Processing

depends on the atomic organization of particle but can produce more complex structures, size range, and shapes

Types of Bottom-up Approach

Aerosol Process, Droplet Formation, Precipitation Process, Sol-Gel Process

Aerosol Process

involves evaporation, condensation, coagulation, and coalescence

aerosol process

most common in producing powder of film form

Droplet Formation

turned into powder through pyrolysis; direct reaction with gas

Precipitation Process

a precipitating agent or solution is used to yield the particle as precipitates

Sol-Gel Process

distribution of nanoparticles in water or organic solvents through hydrolysis, condensation and polymerization

sol-gel process

used for producing porous nanomaterials, ceramic nanostructured polymers as well as oxide nanoparticles