Preface

The first two volumes of the book “Advanced Materials and Nano Systems: Theory and Experiment Parts 1 and 2” were a great success. I received numerous overwhelming responses and best wishes from both the readers and well-wishers. This has motivated me a lot and encouraged me to work on the third volume of “Advanced Materials and Nano Systems: Theory and Experiment”. Furthermore, I am supported by two dynamic and experienced scientists who are working in the field of nanoscience and nanotechnology, Dr. Kingsley O. Obodo from South Africa and Dr. Jitendra Pal Singh from India. They helped me in the selection and scrutiny of the best 11 chapters. The best 11 selected chapters contain very popular topics related to novel nanomaterials for drug delivery, environmental safety, industrial biocatalysts, energy harvest, electronics, etc. As usual with previous volumes of the book, this upcoming edition will be very exciting and will include interesting chapters in the said field from very expert authors and researchers from all over the world. The title of the book, “Advanced Materials and Nano Systems: Theory and Experiment”, is fascinating and truly subject-specific on an international level, which easily captures the attention of readers who are working in the field of nanoscience and nanotechnology. This book also covers a wide range of scientific topics, ranging from bulk materials to nanomaterials and their applications. Advances in materials science via nanotechnology have resulted in significant advancements in a variety of disciplines, such as biomedicine, biomaterials, biosensors, nanoelectronics, energy production, construction, packaging, food, health care, automotive, and defense, among others. Knowing the rapid popularity of nanotechnology and its benefits, we have decided to compile this third edited book; hence, we have invited numerous chapters from active researchers who are working in the thrust areas of nanomaterials.

The opening of Chapter 1 by Shomaila Khanam and Sanjeeb Kumar Rout contributes to the role of plasmonic metal-semiconductor heterostructure in photocatalytic hydrolysis and degradation of toxic dyes. In this experimental work, they have reported the efficiency of plasmonic metal-semiconductor heterostructure as a superior material for photocatalytic water splitting activity for clean and cheap energy generation via the localized surface plasmon resonance (LSPR) method. The LSPR generation by these kinds of materials has proved to be very efficient in the photocatalytic hydrolysis of the hydrogen-rich compound, photocatalytic water splitting, and photocatalytic degradation of organic dyes.

Chapter 2 gives details on BaZrO₃-based ceramics and composites as smart materials for advanced applications. This chapter's introductory section provides a brief history of ceramic materials and their schematic development. Ceramic materials have been used in everything from pottery to pellets, ammunition to antennas, and electrolytes to electronics. This chapter focuses on the barium zirconate (BaZrO₃)-based ceramic composite as smart materials for advanced applications targeting the energy sector, photocatalyst for hydrogen production, a smart bullet in defense, and microwave dielectric resonators for wireless communication systems, respectively.

In Chapter 3, Houmad et al. used density functional theory (DFT) to investigate the 2D graphene-like nanomaterial Sili-graphene as a high-capacity anode material for lithium-ion batteries. Herein, they predict silicon-doped graphene (Siligraphene) as an efficient anode material for potential Li-ion batteries (LIBs). They reported the most stable lithium adsorption at different sites in the hexagonal structure of the silica sheet. Also, they have calculated a very important parameter, the Li-ion migration efficiency in siligraphene, for the LIBs. The reported diffusivity was found to be about 0.095 eV for Li on top of silicon atoms and about

0.223 eV for oxygen, indicating rapid charging and discharging processes. They also report a minute variation in the voltage essential for its potential applications in LIBs.

In Chapter 4, Singh and Devi present an introduction to the fabrication of white light-emitting diodes. They have highlighted the fascinating and eco-friendly sources of white light-emitting diodes due to their high energy savings in various fields, including lighting, architecture, medicine, etc. In this study, they focus on the development and fabrication of cheap and eco-friendly light sources (white light emitting diodes), as the lighting sector is one of the most important and attractive fields because it consumes a large amount of electricity, about 15–20% of total electricity production in the world. They emphasize the two fabrication methods for white light-emitting diodes. The luminous efficiency and rendering index of a lamp are influenced by the type of fabrication. In this chapter, the different fabrication methods for white light-emitting diodes are discussed. The chapter is divided into three parts. The first part is devoted to the general introduction of the light-emitting diode (LED), its working principle, and its applications. In the second part, the characteristics of light, including CIE, colour temperature, and rendering index, are briefly discussed. In the last part, the different methods of fabrication and their advantages and disadvantages are discussed.

Chhana et al. investigated the electronic and piezoelectric properties of non-metal doped II-VI monolayer compounds in Chapter 5. In this study, they have used spin-polarized density functional theory (DFT) to calculate the electronic and piezoelectric properties of the dynamically stable II–VI monolayers: ZnO, ZnS, CdO, and CdS. They also doped the monolayer system with boron and carbon to analyze the variation of these properties for their integration into potential technological applications. They report the half-metallicity of the above-stated monolayers when doped with B and C atoms. The presence of half-metallicity in doped monolayers is promising for spintronic applications. The B-doped ZnO and ZnS monolayer results in negative structural stiffness and negative piezoelectric tensors, while C-doping provides stable and enhanced elastic as well as piezoelectric properties of the monolayer.

Habib Rached and Ismail Ouadha contributed to Chapter 6. They reported a theoretical calculation on the new quaternary MAX-phase compounds (Zr1-xTix)₃AlC₂ (where x = 0-1). They mainly studied the structural, electronic, mechanical, and thermodynamic properties of the MAX phases (Zr_1-xTi_x)₃AlC₂ compounds by using the full-potential plane-wave FP-LAPW method as implemented in the Wien2k code. They have reported the importance of exchange-correlation functionally, in which they have adopted the most commonly adopted exchange-correlation (XC) energy of all electrons within the Perdew-Burke-Ernzerhof parametrization. They reported an agreement between their theoretical findings with the experimental results. They studied the formation energy to check the ground-state stability of the system. The negative value of formation energy confirms the stability of their compounds. The calculation of the electronic structure in the MAX phase found it to be metallic with prominent p-d hybridization. They have also studied the elastic properties by calculating the elastic constants using the Hex-elastic package. They report the mechanical stability of the MAX-phase compound. This chapter also includes a study of the temperature and pressure effects on bulk modulus, Debye temperature, and heat capacity at constant volume (CV) and constant pressure (CP), respectively.

Chapter 7 highlights the work of Obodo et al. Here, they studied the surface segregation in Pt₃Nb and Pt₃Ti using density-functional-based methods. In their DFT-based studies, they reported the surface segregation of the stoichiometrically ordered Pt₃X system because, due to the endothermic process of direct exchange in Pt₃Ti, the exchange of surface atoms is forbidden in the ground state. Direct exchange in Pt3Nb was also reported as exothermic surface segregation. They describe an intriguing phenomenon in which an overlayer forms on the Pt₃X system as a result of PtX migration into an antisite defect in an off-stoichiometric configuration. Doped surfaces, rather than pristine structures, have the optimal oxygen adsorption energy for Pt(111). The instability was found in the Pt₃X system with the X-skin surface configuration. While the Pt-skin configuration improved the adsorption energy, the inclusion of the antisite configuration improved ORR activity for both Pt₃X systems. Finally, they found that Pt3Nb had better catalytic performance than Pt₃Ti.

Chapter 8: This chapter is contributed by Roy and his group, and their work is a review of the nanoparticles and their manipulation for capturing the toxic elements from the air to keep the environment healthy. The high surface area to volume ratio of extremely small particles (nanoparticle size between 1-100 nm) accounts for their distinct behavior. They report the importance of artificially synthesized and manipulated nanoparticles as per the specific needs. Alarming impact on the environment as a result of the massive use of nanoparticle-based industrial products degrades environmental health. Environmental health is determined by the quality of the air, water, and soil, which is reflected in a healthy ecosystem and its biodiversity. The effects of nanoparticles released into the environment vary depending on their type, surface coating, and degree of environmental transformation. Some nanoparticles are harmful to the environment, and some are beneficial. Some of the nanoparticles in the environment get bioaccumulated in plants and animals, disturbing their growth and productivity. Recognizing the potential of nanotechnology in manipulating nanoparticles, remediation has proven to be an effective technique for removing some toxic elements and compounds from the environment, thereby providing a way to reduce pollution efficiently. In this review, they have presented an overview of the sources, fate, and effects of nanoparticles available in air, water, and soil. They also promise the long-term assessment of nanoparticles and the formulation of strict guidelines for their usage by the concerned industries for better environmental health and, in turn, a healthy ecosystem.

Chapter 9 includes the research work of Lalhumhima et al., who reported the optimal site for the adsorption and population effect of lithium on a silicene monolayer. This is a purely theoretical work based on density functional theory's first principles. They report the most stable site for adsorbing the lithium ions in the silicene monolayer. They discovered the active site by calculating the minimum adsorption energy required to place the lithium atom in various possible locations. They reported that the center of the hexagonal structure in silicene was the most favorable site. Using transition state search (TSS), the optimized stable state and a low diffusion energy barrier (DEB) of 0.348 eV were indicated. The metallic property of pristine silicene is maintained throughout Li atom adsorption.

Chapter 10 details the methods for synthesizing the metal oxide nanoparticles as well as the difficulties. They have emphasized the significance of nanoscience and nanotechnology in raising the standard of living. The advancement of nanotechnology is facilitated by the new class of materials known as nanoparticles (NPs). The NPS should have at least one particle dimension between 1 and 100 nm. The synthesis methods can change the size and structure of NPs, which are important in molecular biology, physics, organic and inorganic chemistry, biology, medicine, and materials research. Synthesis techniques can produce NPs with high surface areas, increasing their value and supplying necessary features like surface reactivity. They discussed the various methods for creating nanoparticles. They concentrate on the two parts, top-down and bottom-up, which are categorized according to the raw materials used to create the NPs in this study. An overview of synthesis techniques and their uses in nanotechnology and nanoscience was given in this review. The electrochemical discharge procedure, a revolutionary method for creating NPs, is covered in detail. Tables are used to discuss the synthesized materials, including ZnO, carbon, graphene, and other metal oxides, as well as their composites. Finally, the difficulties, benefits, drawbacks, conclusions, and synthesis of NPs are examined.

The final chapter, 11 by Singh and Devi, discusses the Heterogeneous semiconductor photocatalysis for water purification: Basic mechanism and advanced strategies. In this chapter, they have discussed the different techniques based on the semiconductor photocatalysis for water purification. They specially emphasize the contribution of water pollution via anthropogenic activities, human waste, utilization of toxic chemicals in agricultural activities etc., and the solution of purification of water to make it drinkable with the help of nanotechnology. Heterogeneous semiconductor photocatalysis is the most effective green method in this regard because it enables it to degrade into nonhazardous products like CO₂ and H₂O without releasing any harmful residue. Therefore, understanding the knowledge of photocatalysis mechanism is very significant to enable further improvement. Hence, this chapter presents the basic mechanism of photocatalysis, its drawbacks and the advanced strategies to improve the catalytic efficiency. Finally, some of the important factors that influence catalytic activity have also been discussed.

In the current book, various computational and experimental techniques of recent advances in materials science are presented, with a primary emphasis on the synthesis, characterization, and analysis of functional properties of novel nanomaterials to address a variety of problems encountered on a daily basis. This book's timely release should be of interest to scholars, professors, and students in the field of nanotechnology. Given the increasing demand for nanomaterials in various human activities, it is anticipated that the topic of advanced materials and nanosystems from theory and experimental perspectives will continue to be at the forefront of cutting-edge research in science and technology for the foreseeable future. With a focus on the synthesis, characterization, and analysis of functional properties of innovative nanomaterials to solve a variety of problems encountered on a daily basis, the current book presents numerous computational and experimental approaches to recent breakthroughs in materials science.

The timely publication of this book (Part 3) should be of great interest to professionals, educators, researchers and students in the field of materials science and nanotechnology. It is projected that the subject of nanomaterials and nanotechnology will remain at the forefront of cutting-edge research in science and technology for the foreseeable future, given the growing integration of nanomaterials in numerous human activities. I also want to express my gratitude to the editorial team of the Bentham Books for their prompt release of Parts 1 and 2 of “Advanced Materials and Nano Systems: Theory and Experiment”, which gave me the confidence I needed to quickly collect the chapters compile them and finish Part 3.