Chapter 13
Metal Cluster Catalysis
13.1 Introduction
To develop metal catalysts for the selective activation of certain chemical bonds (e.g.,
C–H) is attractive and challenging research topics in chemistry [1–8]. Noble metals
and heavy metals dominant the studies and practical use of this field, because main
group metals and early transition metals are too reactive to be effective catalysts.
Among others, unremitting efforts have also been paid to study catalysis without
precious metals [9]. For example, it has been recognized that by incorporating nonmetallic elements (e.g., carbon or oxygen) into the early transition metal, the surface
reactivity of the metal can be moderated to produce an effective catalyst. Extensive
studies have demonstrated that oxygen-centered radicals can serve as active sites to
activate C–H bonds of alkane molecules (such as methane, ethane, and butane etc.)
under thermal collision conditions [10–29]. The activation of alkane molecules by
oxygen-centered radicals over atomic clusters usually lead to single hydrogen atom
abstraction (HAA) [17, 30], forming products of alkyl radicals.
Catalysis is generally caused by the ensemble operation of the intermediates on
active sites and rationalized by correlative elementary reactions, along with reaction
kinetics simulation based on first-principles calculations. A joint experimental and
theoretical studies have revealed the catalytic activity of abundant metal clusters,
and interpreted the catalysis mechanism on a basis of bond activation and reconstruction, active sites and reactive intermediates, role of promoting additives, and
site-dependence of turnover frequency which evaluates the mole number of yields
regarding to a mole catalysts per hour [31]. While it has been attainable to detect the
adsorbed intermediates of clusters or molecules by gas-phase mass spectrometry or
to observe single adsorbed atoms by STM in situ analysis [32], it is also expected to
direct and control a catalytical reaction process in gas phase and on solid surfaces
[33]. In particular, in recent years there is a new concept known as single-atom catalysis which stimulates reasonable research interest with vivid catalysis for reactions,
such as platinum-based heterogeneous catalysis for CO oxidation [34].
© The Editor(s) (if applicable) and The Author(s), under exclusive license
to Springer Nature Singapore Pte Ltd. 2020
Z. Luo and S. N. Khanna, Metal Clusters and Their Reactivity,
https://doi.org/10.1007/978-981-15-9704-6_13
215
Metal Cluster Catalysis
13.1 Introduction
To develop metal catalysts for the selective activation of certain chemical bonds (e.g.,
C–H) is attractive and challenging research topics in chemistry [1–8]. Noble metals
and heavy metals dominant the studies and practical use of this field, because main
group metals and early transition metals are too reactive to be effective catalysts.
Among others, unremitting efforts have also been paid to study catalysis without
precious metals [9]. For example, it has been recognized that by incorporating nonmetallic elements (e.g., carbon or oxygen) into the early transition metal, the surface
reactivity of the metal can be moderated to produce an effective catalyst. Extensive
studies have demonstrated that oxygen-centered radicals can serve as active sites to
activate C–H bonds of alkane molecules (such as methane, ethane, and butane etc.)
under thermal collision conditions [10–29]. The activation of alkane molecules by
oxygen-centered radicals over atomic clusters usually lead to single hydrogen atom
abstraction (HAA) [17, 30], forming products of alkyl radicals.
Catalysis is generally caused by the ensemble operation of the intermediates on
active sites and rationalized by correlative elementary reactions, along with reaction
kinetics simulation based on first-principles calculations. A joint experimental and
theoretical studies have revealed the catalytic activity of abundant metal clusters,
and interpreted the catalysis mechanism on a basis of bond activation and reconstruction, active sites and reactive intermediates, role of promoting additives, and
site-dependence of turnover frequency which evaluates the mole number of yields
regarding to a mole catalysts per hour [31]. While it has been attainable to detect the
adsorbed intermediates of clusters or molecules by gas-phase mass spectrometry or
to observe single adsorbed atoms by STM in situ analysis [32], it is also expected to
direct and control a catalytical reaction process in gas phase and on solid surfaces
[33]. In particular, in recent years there is a new concept known as single-atom catalysis which stimulates reasonable research interest with vivid catalysis for reactions,
such as platinum-based heterogeneous catalysis for CO oxidation [34].
© The Editor(s) (if applicable) and The Author(s), under exclusive license
to Springer Nature Singapore Pte Ltd. 2020
Z. Luo and S. N. Khanna, Metal Clusters and Their Reactivity,
https://doi.org/10.1007/978-981-15-9704-6_13
215