Contents


**1**

**Chapter 1**

**1. Preface**

tion, and storage.

Conversion

*Nikolay Britun and Tiago Silva*

which normally happen without plasma.

to the development of the modern society.

**2. Historical remarks**

Introductory Chapter: Plasma

The aim of this book is to cover recent advances in the field of plasma chemistry and, in particular, to explore the role of low-temperature discharges for efficient greenhouse gas conversion, synthesis of valuable chemicals, potential fuel produc-

Low-temperature plasmas produced by electric discharges represent unique non-equilibrium state of matter where electrons possess much higher temperatures than neutrals and ions. This distinctive feature opens new possibilities for production of highly reactive species in a chemically rich environment close to the room temperature in the wide range of gas pressure, which may vary from mTorr range to a fraction of atmosphere. Moreover, the discharge conditions far from thermodynamic equilibrium may further intensify the "traditional" chemical processes,

Low-temperature discharges are deeply related to a large number of important technologies with extraordinary societal and environmental benefits. For example, since the second half of the nineteenth century, low-temperature plasma has been used to improve the microelectronics industry [1]. Indeed, these discharges are able to provide ion fluxes that are responsible for surface modifications by sputtering, etching, activation, and deposition, which are of a critical importance for the development of any micro device. Other domains in which low-temperature plasmas play an important role involve light sources [2], lasers [3], sterilization of biological samples [4], etc. All of these technologies make important contributions

The use of low-temperature plasmas for chemical conversion of the greenhouse gases has a rich history and can be traced back to the 1970s–1980s, namely, to the research related to CO2 transformation into the valuable chemicals conducted in the former USSR (see [5] and therein). During this period the experimental and theoretical background on the plasma-chemical processes has been mainly understood (see [6] and therein). Interestingly, it was already estimated theoretically that the limit of the energy efficiency of CO2 decomposition (term defined in the following chapters) in microwave discharges can reach about 43% in the equilibrium regime and about 80% in the non-equilibrium regime [5]. The corresponding experimental results related to these efficiencies have shown excellent agreement with the estimates [5–7].

Chemistry for Better CO2
