266
15 Future Directions
Such a development will present a transformational approach to catalysis with the
possibility of significantly high activity due to a large extent of uncoordinated atoms.
Another growing area of research is the catalysis by supported clusters. The
primary role of support systems in metal-catalyzed heterogeneous catalysis has
historically centered on the ability to provide a high surface area to which metal clusters can be affixed, thus limiting deactivation through sintering. However, the emergence of shape selective catalysts in hydrothermal cracking applications provides an
excellent example of how supports can add additional value to catalytic processes. For
example, the use of titanium, cerium, and zirconium oxides as substrate promoters
in cobalt-catalyzed Fischer-Tropsch reactions offers an additional example of how
supports can contribute to heterogeneous catalytic activity. As we show in Chap. 9,
the support can play a more active role in catalysis by acting as a ligand that can
allow charge flow thus enabling one to reduce reaction barriers on supported clusters
during oxidation and reduction steps. These developments that need further work can
be transformational in reducing cost for pharmaceutical drugs opening the pathway
to “medicine for everybody”.
Most of the catalysts currently used in industry are based on precious metals and
there is a tremendous interest in developing catalysts using cheaper metals. The development of superatoms [3–5], where the clusters of a given element can mimic the
chemical behavior of another element provides a viable alternative. Such findings will
be further extended to binary metals and compound systems, allowing a lollapalooza
effect of both electronic and geometric structures identified to govern the stability
and presence of reactive sites. It is anticipated of superatom building blocks for new
materials with tailored properties, for instance, isovalent inexpensive clusters will
lead to a new generation of catalysts, as well as magnetic superatoms for spin electronics, and superatomic semiconductive clusters for transistors. A success of future
applications of metal nanoclusters will rely on the availability of low-dimensionally
assembled materials. For this purpose, the genetic structures of superatom clusters
are expected to open a new research areas [6].
Moreover, there could be research topics on the energetics-related metal cluster
reactions with organic molecules which simulate fuels. Such reactions conducted in
endothermic conductions will bring important implications to aviation and rockets,
namely the ability to acquire large thrust without undue stress being placed on the
aircraft engines and related components. With well-selected conditions, the engines
run efficiently acquiring better combusting rates. Investigations on exothermic cluster
reactions will stimulate researchers to look for promising reactant pairs which may
also be undertaken with binary metal cluster systems.
While it is well recognized that clusters of selected composition, stoichiometry,
and charge-state provide ideal systems for studying heterogeneous catalysis and
energetics-related reactions, there could be anticipated research interest devoted to
understanding the principles and measures upon anticorrosion which cost a great
deal of money especially in naval vessels, cross-sea bridge, water piping system,
hydroelectric-dam reservoirs, etc. A few future directions of this topic could involve
the investigations to understand the physical or chemical damage of metal surfaces by
environmental interactions, to unravel the principles and mechanism corresponding
15 Future Directions
Such a development will present a transformational approach to catalysis with the
possibility of significantly high activity due to a large extent of uncoordinated atoms.
Another growing area of research is the catalysis by supported clusters. The
primary role of support systems in metal-catalyzed heterogeneous catalysis has
historically centered on the ability to provide a high surface area to which metal clusters can be affixed, thus limiting deactivation through sintering. However, the emergence of shape selective catalysts in hydrothermal cracking applications provides an
excellent example of how supports can add additional value to catalytic processes. For
example, the use of titanium, cerium, and zirconium oxides as substrate promoters
in cobalt-catalyzed Fischer-Tropsch reactions offers an additional example of how
supports can contribute to heterogeneous catalytic activity. As we show in Chap. 9,
the support can play a more active role in catalysis by acting as a ligand that can
allow charge flow thus enabling one to reduce reaction barriers on supported clusters
during oxidation and reduction steps. These developments that need further work can
be transformational in reducing cost for pharmaceutical drugs opening the pathway
to “medicine for everybody”.
Most of the catalysts currently used in industry are based on precious metals and
there is a tremendous interest in developing catalysts using cheaper metals. The development of superatoms [3–5], where the clusters of a given element can mimic the
chemical behavior of another element provides a viable alternative. Such findings will
be further extended to binary metals and compound systems, allowing a lollapalooza
effect of both electronic and geometric structures identified to govern the stability
and presence of reactive sites. It is anticipated of superatom building blocks for new
materials with tailored properties, for instance, isovalent inexpensive clusters will
lead to a new generation of catalysts, as well as magnetic superatoms for spin electronics, and superatomic semiconductive clusters for transistors. A success of future
applications of metal nanoclusters will rely on the availability of low-dimensionally
assembled materials. For this purpose, the genetic structures of superatom clusters
are expected to open a new research areas [6].
Moreover, there could be research topics on the energetics-related metal cluster
reactions with organic molecules which simulate fuels. Such reactions conducted in
endothermic conductions will bring important implications to aviation and rockets,
namely the ability to acquire large thrust without undue stress being placed on the
aircraft engines and related components. With well-selected conditions, the engines
run efficiently acquiring better combusting rates. Investigations on exothermic cluster
reactions will stimulate researchers to look for promising reactant pairs which may
also be undertaken with binary metal cluster systems.
While it is well recognized that clusters of selected composition, stoichiometry,
and charge-state provide ideal systems for studying heterogeneous catalysis and
energetics-related reactions, there could be anticipated research interest devoted to
understanding the principles and measures upon anticorrosion which cost a great
deal of money especially in naval vessels, cross-sea bridge, water piping system,
hydroelectric-dam reservoirs, etc. A few future directions of this topic could involve
the investigations to understand the physical or chemical damage of metal surfaces by
environmental interactions, to unravel the principles and mechanism corresponding