Nanoceramics: Synthesis, Characterizations and Applications
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of alumina, zirconia, titania, ceria, beryllia, etc., (ii) non-oxides such as borides,
carbides, nitrides, silicide, etc., and (iii) composite ceramics such as particulate
reinforced, fiber reinforced combinations of oxides and non-oxides [8]. Advanced
nanoceramics have profound surface properties as their surface to volume ratio is
more than 10% when their particle size goes below 100 nm at least in one dimension
[9].
2 Synthesis of Nanoceramics
Nanoceramics can be produced by various techniques that apply both wet and dry
conditions. Most of the synthesis methods use liquid as media and factors such as
type of suspension, packing of particles and their dispersion play a great role in
their synthesis and outcome. The method of synthesis not only defines the size and
shape of nanoceramics but also influences its characteristics such as crystal habits,
specific surface area and state of agglomeration [10]. Further, size and shape of
the nanoparticles can be molded by adsorbing organic molecules on the surface
of growing nanoparticles [11]. Nanoparticles tend to agglomerate due to their high
surface area and thermodynamic instability and the synthesis method adopted should
involve strategies to overcome this for effective usage [12].
Synthesis of nanoceramics can be broadly classified into two approaches (i) Topdown approach where a large particle is broken down into nanosized particles and (ii)
bottom-up approach where ions, atoms, molecules or nanoparticles are assembled in
a controlled manner to form nanoparticles. There are various methods of synthesis
which come under any of these two broad classifications. The synthesis method
plays a great role in the functionality of the produced nanoceramics. The focus
of this chapter is on nanoceramics and its application as biomaterials. Hence, we
will limit our discussion to the different synthesis methods by which nanoceramics
that are used as biomaterials are produced. The common methods of synthesis of
nanoceramics include mechanochemical synthesis, co-precipitation, sol-gel method,
spray pyrolysis, microemulsion method, physical vapour deposition, etc., which are
discussed in detail below [13].
2.1 Physical Vapour Deposition
Physical vapour deposition is a high vacuum coating technique that comprises
vacuum deposition methods to produce thin coatings and films of pure metal or
alloy. The material to be coated is heated and the metal in the condensed phase is
converted to vapour phase [14]. In the vapour phase, the material gets supersaturated in an inert atmosphere to condense the metal nanoparticles and then deposits as
thin adherent film of the condensed phase on electrically conductive material [15].
It is possible to develop a much thinner layer of the nanoceramic material over the
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of alumina, zirconia, titania, ceria, beryllia, etc., (ii) non-oxides such as borides,
carbides, nitrides, silicide, etc., and (iii) composite ceramics such as particulate
reinforced, fiber reinforced combinations of oxides and non-oxides [8]. Advanced
nanoceramics have profound surface properties as their surface to volume ratio is
more than 10% when their particle size goes below 100 nm at least in one dimension
[9].
2 Synthesis of Nanoceramics
Nanoceramics can be produced by various techniques that apply both wet and dry
conditions. Most of the synthesis methods use liquid as media and factors such as
type of suspension, packing of particles and their dispersion play a great role in
their synthesis and outcome. The method of synthesis not only defines the size and
shape of nanoceramics but also influences its characteristics such as crystal habits,
specific surface area and state of agglomeration [10]. Further, size and shape of
the nanoparticles can be molded by adsorbing organic molecules on the surface
of growing nanoparticles [11]. Nanoparticles tend to agglomerate due to their high
surface area and thermodynamic instability and the synthesis method adopted should
involve strategies to overcome this for effective usage [12].
Synthesis of nanoceramics can be broadly classified into two approaches (i) Topdown approach where a large particle is broken down into nanosized particles and (ii)
bottom-up approach where ions, atoms, molecules or nanoparticles are assembled in
a controlled manner to form nanoparticles. There are various methods of synthesis
which come under any of these two broad classifications. The synthesis method
plays a great role in the functionality of the produced nanoceramics. The focus
of this chapter is on nanoceramics and its application as biomaterials. Hence, we
will limit our discussion to the different synthesis methods by which nanoceramics
that are used as biomaterials are produced. The common methods of synthesis of
nanoceramics include mechanochemical synthesis, co-precipitation, sol-gel method,
spray pyrolysis, microemulsion method, physical vapour deposition, etc., which are
discussed in detail below [13].
2.1 Physical Vapour Deposition
Physical vapour deposition is a high vacuum coating technique that comprises
vacuum deposition methods to produce thin coatings and films of pure metal or
alloy. The material to be coated is heated and the metal in the condensed phase is
converted to vapour phase [14]. In the vapour phase, the material gets supersaturated in an inert atmosphere to condense the metal nanoparticles and then deposits as
thin adherent film of the condensed phase on electrically conductive material [15].
It is possible to develop a much thinner layer of the nanoceramic material over the