**Preface XI**


Preface

Cerium oxide (CeO2), which is one of important transition metal oxides, acts as an n-type semiconductor material. It is clear from the title that this book is related to CeO2. CeO2 has a cubic fluorite structure, in which each cerium atom is surrounded by eight equivalent oxy‐ gen atoms and each oxygen atom is surrounded by a tetrahedron of four cerium atoms. CeO2 has shown various applications, particularly adsorption, catalysis, photocatalysis, sensing, fuel cells, hydrogen production, semiconductor devices, as well as biomedical uses. CeO2 is also used in petroleum refining and emission controlling systems in gasoline en‐ gines, as well as a diesel fuel-borne catalyst to reduce particulate matter emissions. In recent years, CeO2 nanoparticles have gained greater consideration in the biomedical research com‐ munity since it can be used as an inhibiting cellular agent along with its antimicrobial and antioxidant activities. Because of the dramatic and widespread industrial uses of CeO2 mate‐ rials, it was thought appropriate to present recent developments in the applications and at‐ tributes of CeO2 in the form of a book to the scientific community. This book contains six chapters, which describe the structure, different uses, applications, and attributes of CeO2. The first chapter is "Cerium oxides for corrosion protection of AZ91D Mg alloy" by A. P. Loperena et al. The chapter describes CeO2-based coatings as an environmentally friendly option to enhance the corrosion resistance of magnesium alloys. The formation of a coating from a solution containing cerium nitrate was studied for controlling the biodegradation

The second chapter is "Doped CeO2 for solid oxide fuel cells" by Shobit Omar. It describes the highlights of various activities regarding doped CeO2 materials in fuel cell applications

The third chapter is "Prototyping a gas sensor using CeO2 as a matrix or dopant in oxide semiconductor systems" by Lucian Pîslaru-Dănescu et al. In this chapter, two important as‐ pects of using CeO2 in the field of gas sensors are discussed. First, the use of binary semicon‐ ductor oxides CeO2–Y2O3 for CO2 detection in the range of 0–5000 ppm. Second, the use of CeO2 as a dopant in a hydride composite, consisting of reduced graphene oxide/ZnO, to in‐

The fourth chapter is "Waterborne acrylic/CeO2 nanocomposites for UV blocking clear coats" by Miren Aguirre et al. In this chapter, the authors describe the UV absorbing capaci‐ ty of CeO2 nanoparticles and the film-forming capacity of acrylic polymers. It presents the synthetic route to produce waterborne acrylic/CeO2 hybrid nanocomposites for UV absorb‐

and the mechanisms underlying the oxygen-ion conduction process in doped ceria.

crease sensibility in NOx detection at low concentration in the range of 0–10 ppm.

rate of AZ91D magnesium alloy in simulated physiological solution.
