1
© Springer Nature Switzerland AG 2020
R. Adzic, N. Marinkovic, Platinum Monolayer Electrocatalysts,
https://doi.org/10.1007/978-3-030-49566-4_1
Chapter 1
Short Introduction to the Science
of Electrocatalysis
In general terms, electrochemistry is concerned principally with chemical reactions
that are associated with the transfer of electrons or ions across interfaces. The most
typical electrochemical interface is between a solid metal and a liquid solution of an
electrolyte (ionic conductor), but any interface involving a predominantly electronic
conductor and a predominantly ionic conductor is considered to be an electrochemical interface.
Interfacial reactions are governed by the potential distribution across the interface in a so-called electric double layer. The electric double layer is formed by the
accumulation of excess charges of equal amount at the interface with a very small
distance between such formed layers, which are similar to condenser plates. As a
consequence of small separation of charges, the electrochemical interfaces have
very high capacitance. Another consequence of the small inter-plate distance and of
a typical voltage drop of 1 V between them is an extremely high electric field of
10
9
Vm
−1
in the double layer. This is another characteristic of electrochemical interfaces that cannot be achieved at the metal vacuum counterparts.
The capacitance, in addition to ohmic resistance, determines the rate with which
we can change the electrode potentials. Since the double-layer capacity is large, the
time required to change electrode potential from one value to another is about 1
microsecond with the best potentiostats. The interfacial regions can be modified by
various adsorbates to produce very different electrode surface properties that are
particularly important for the area of electrocatalysis, which addresses the effect of
nature and structure of electrode surfaces on reaction kinetics. Electrochemistry has
important applications in various areas of technology such as energy storage and
conversion, large-scale production and refining of almost all nonferrous metals, production of inorganic chemicals, organic synthesis, corrosion prevention, electrochemical sensors, and biomedical applications.
© Springer Nature Switzerland AG 2020
R. Adzic, N. Marinkovic, Platinum Monolayer Electrocatalysts,
https://doi.org/10.1007/978-3-030-49566-4_1
Chapter 1
Short Introduction to the Science
of Electrocatalysis
In general terms, electrochemistry is concerned principally with chemical reactions
that are associated with the transfer of electrons or ions across interfaces. The most
typical electrochemical interface is between a solid metal and a liquid solution of an
electrolyte (ionic conductor), but any interface involving a predominantly electronic
conductor and a predominantly ionic conductor is considered to be an electrochemical interface.
Interfacial reactions are governed by the potential distribution across the interface in a so-called electric double layer. The electric double layer is formed by the
accumulation of excess charges of equal amount at the interface with a very small
distance between such formed layers, which are similar to condenser plates. As a
consequence of small separation of charges, the electrochemical interfaces have
very high capacitance. Another consequence of the small inter-plate distance and of
a typical voltage drop of 1 V between them is an extremely high electric field of
10
9
Vm
−1
in the double layer. This is another characteristic of electrochemical interfaces that cannot be achieved at the metal vacuum counterparts.
The capacitance, in addition to ohmic resistance, determines the rate with which
we can change the electrode potentials. Since the double-layer capacity is large, the
time required to change electrode potential from one value to another is about 1
microsecond with the best potentiostats. The interfacial regions can be modified by
various adsorbates to produce very different electrode surface properties that are
particularly important for the area of electrocatalysis, which addresses the effect of
nature and structure of electrode surfaces on reaction kinetics. Electrochemistry has
important applications in various areas of technology such as energy storage and
conversion, large-scale production and refining of almost all nonferrous metals, production of inorganic chemicals, organic synthesis, corrosion prevention, electrochemical sensors, and biomedical applications.