An Introduction to Green Nanotechnology

Mahmoud Nasrollahzadeh, Mohammad S. Sajadi, Monireh Atarod, Mohaddeseh Sajjadi, Zahra Isaabadi

• Publisher: Academic Press
• Year: 2019
• Print ISBN: 9780128135860
• eBook ISBN: 9780128135877
• Topic: Physical Sciences
• Subtopic: Nanoscience

An Introduction to Green Nanotechnology, Volume 28, provides students, scientists and chemical engineers with an overview of several types of nanostructures, discusses the synthesis and characterization of nanostructures, and provides applications of nanotechnology in daily life. The book offers a foundation to green nanotechnology by explaining why green nanotechnology is important. Covers biological sources in green nanotechnology, antioxidants, green nanostructures, mechanism, synthesis and characterization. The book ends with an evaluation of the risks of nanotechnology in human life and future perspectives.- Introduces novel sources of plants having a high potential to be used as bio media to synthesize nanostructures- Provides phytochemical properties and antioxidant potential, and their effects on stability, morphology and size of green nanostructures- Includes a medicinal and technological comparison of green synthesized nanostructures to nano-products from non-green methods- Uses accessible language, avoiding complex concepts of mathematics, biology and chemistry

Chapter 1

An Introduction to Nanotechnology

Mahmoud Nasrollahzadeh; S. Mohammad Sajadi; Mohaddeseh Sajjadi; Zahra Issaabadi

Abstract

Nanotechnology represents a revolutionary path for technological development that concerns the management of material at the nanometer scale (one billion times smaller than a meter). Nanotechnology factually means any technology on the nanoscale that has numerous applications in the real world. Nanotechnology literally encompasses the fabrication and application of chemical, physical, and biological systems at scales ranging from individual molecules or atoms to submicron dimensions, and also the integration of these resulting nanomaterials into larger systems. It has the potential to change our perspectives and expectations and provide us with the capability to resolve global issues. The discovery and use of carbon nanomaterials has allowed the introduction of many new areas of technology in nanomedicine, biosensors, and bioelectronics. In recent years, nanotechnology has emerged as a multidisciplinary field, in which gaining a fundamental understanding of the electrical, optical, magnetic, and mechanical properties of nanostructures promises to deliver the next generation of functional materials with wide-ranging applications. Nanostructures can also provide solutions to technological and environmental challenges in the areas of catalysis, medicine, solar energy conversion, and water treatment.

Keywords

Nanotechnology; Nanomaterials; Carbon nanotubes; Graphene; Nanoscale; Top-down; Bottom-up

1.1 Introduction

Nanotechnology is a mindset, even though the scientific community is fascinated with the field of nanoscience, most of the ongoing discussions, definitions, and attention is focused on nanotechnology. As such, it represents a broad term which demonstrates the apotheosis of man's ceaseless urge for knowledge having practical potential. The meaning of the term nanotechnology is any technology operating on the nanoscale which has applications in the real world, that is, to employ single atoms and molecules to form functional structures [1]. The field of nanotechnology involves the creation and utilization of chemical, physical, and biological systems with structural features between single atoms or molecules to submicron dimensions, and also the assimilation of resultant nanostructures into larger systems [2, 3].

The simplest definition of nanotechnology is “technology on the nanoscale.” Subsequently, various definitions of nanotechnology have evolved. This original definition requires further development, such as a definition of what is meant by nanoscale. Thus we cannot properly define nanotechnology unless we define “nanoscale,” that is, a scale covering 1–100 nm. A brief definition of nanotechnology is an “atomically precise technology” or “engineering with atomic precision” [4]. Nanotechnology is connected with systems and materials, the components and structures of which represent novel, significantly improved chemical, physical, and biological properties, processes, and phenomena because of their nanoscale size. The dictionary definition of nanotechnology is “the design, characterization, manufacture and shape and size-controlled application of matters in the nanoscale” [5]. A substitute definition from the same dictionary is “the careful and controlled manipulation, precision placement, modeling, measurement, and production of materials at the nanoscale in order to make matters, systems, and devices by fundamentally novel properties and functions” [5]. Nanotechnology is a branch of knowledge, within a subclassification of technology in colloidal science, chemistry, physics, biology, and other scientific fields, encompassing the study of phenomena at the nanoscale [6].

The essence and promise of nanoscience and nanotechnology are illustrated in the fact that the properties of materials (i.e., chemical, physical, and biological) at the nanoscale may be quite different from those within a bulk material [7]. When the dimensions of a material are reduced below 100 nm dramatic alterations may occur in their properties [7]. Materials therefore might be nanostructured in order to provide a specific performance or to provide new properties to a material in addition to changes linked specifically to size and structure. Such macromolecules and particles made of a small number of molecules, at sizes of 1–50 nm, possess distinct physicochemical properties [8]. Compared with bulk materials, nanoparticles (NPs) possess properties of increased performance when they are used for similar applications. The definition of an NP is a collective of atoms bonded together with an average radius between 1 and 100 nm, i.e., typically consisting of 10–10⁵ atoms [9]. A significant application of NPs is the manufacture of a new class of catalysts, identified as nanocatalysts [10]. Considerable advances are being made in fields that contribute to the manufacture and detailed understanding of the nature (particle size, composition, and structure) and function of NPs as catalysts for the improved performance of chemical reactions [11]. The reason for a catalysts performance is a powerful function of its particle size and size distribution. The chemical properties of NPs provide them with advantages as catalysts, such as their large surface-to-volume ratio, surface morphology, and electronic properties, all of which are linked to particle size [6, 12].

The discovery of new materials, phenomena, and processes at the nanoscale, and the advancement of novel theoretical and experimental techniques for research, provide novel chances for the advancement of inventive nanostructured materials and nanosystems. There are many current and expected advancements in nanoscale science and nanotechnology in terms of its applications in agriculture, electronics, medicine, energy, etc. These developments are being made at an increasing rate [10, 13].

Nanotechnology can play a significant role in the extension of innovative methods used to create new products, to substitute present production equipment, to reformulate novel materials and chemicals toward improved performance resulting in reduced material and energy consumption, to reduce harm to the environment, and also for environmental remediation [14]. Although a decreased consumption of matter and energy benefits the environment, nanotechnology provides the exciting possibility to remediate problems via a more sustainable route. Environmental applications of nanotechnology include the development of solutions to current environmental problems, measures to address both the ensuing problems from interactions of material and energy with the environment, and the possible risks associated with nanotechnology [14].

1.2 The Importance of Nanoscale Materials

The Greek prefix “nano” is derived from the word “dwarf” and refers to a reduction in size, or time, of 10^{− 9}, which is 1000 times smaller than a micron [15]. The nanometer (nm) scale is typically defined as one billionth of a meter or three to five atoms in width—equivalent to 10 Å or smaller than one tenth of a micrometer in at least one dimension. However, the term nanoscale is sometimes used even for materials smaller than 1 μm. Also, 1 nm is 10^{− 9} m or 10,000 times less than the diameter of a human hair. Due to study materials with morphological characteristics at the nanoscale, a science-based approach has been derived in the field of nanomaterials, especially applied to those nanomaterials that have special properties [15]. Fig. 1.1 shows size ranges for various microscale and nanoscale objects. Nanoscience and nanotechnology operates with very small objects and systems [16]. Nanoscience studies are defined as those that deal with matter and systems having the following key properties:

• • Have at least one dimension less than 10 nm.
• • Utilize methodologies that illustrate the fundamental control of the physical and chemical characteristics of molecular-scale structures (process).
• • Permit the manufacture of larger structures (building block property).

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Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Dedication
• Chapter 1: An Introduction to Nanotechnology
• Chapter 2: Types of Nanostructures
• Chapter 3: Biological Sources Used in Green Nanotechnology
• Chapter 4: Applications of Nanotechnology in Daily Life
• Chapter 5: Green Nanotechnology
• Chapter 6: Plant-Mediated Green Synthesis of Nanostructures: Mechanisms, Characterization, and Applications
• Chapter 7: Risks of Nanotechnology to Human Life
• Index