Advanced Environmental Analysis: Applications of Nanomaterials, Complete Set

by Chaudhery Mustansar Hussain (Editor), Boris Kharisov (Editor)

Overview

Environmental analysis techniques have advanced due to the use of nanotechnologies in improving the detection sensitivity and miniaturization of the devices in analytical procedures. These allow for developments such as increases in analyte concentration, the removal of interfering species and improvements in the detection limits. Bridging a gap in the literature, these books uniquely bring together state-of-the-art research in the applications of novel nanomaterials to each of the classical components of environmental analysis, namely sample preparation and extraction, separation and identification by spectroscopic techniques. Special attention is paid to those approaches that are considered greener and reduce the cost of the analysis process both in terms of chemicals and time consumption.

Advanced undergraduates, graduates and researchers at the forefront of environmental science and engineering will find these books a good source of information. It will also help regulators, decision makers, surveillance agencies and the organizations assessing the impact of pollutants on the environment.

Product Details

ISBN-13:	9781782629078
Publisher:	RSC
Publication date:	11/16/2016
Series:	Detection Science Series , #9
Pages:	1200
Product dimensions:	6.15(w) x 9.20(h) x (d)

About the Author

Chaudhery Mustansar Hussain, PhD, is an adjunct professor and director of laboratories in the Department of Chemistry and Environmental Sciences at the New Jersey Institute of Technology (NJIT), Newark, New Jersey, United States. His research is focused on the applications of nanotechnology and advanced materials, environmental management, analytical chemistry, and other various industries. Dr. Hussain is the author of numerous papers in peer-reviewed journals as well as a prolific author and editor of many books, including scientific monographs and handbooks in his research areas.

Read an Excerpt

Advanced Environmental Analysis Volume 1

Applications of Nanomaterials

---

By Chaudhery Mustansar Hussain, Boris Kharisov

The Royal Society of Chemistry

Copyright © 2017 The Royal Society of Chemistry
All rights reserved.
ISBN: 978-1-78262-907-8

---

CHAPTER 1

Perspective on Analytical Sciences and Nanotechnology

DEEPALI SHARMA, SUVARDHAN KANCHI, KRISHNA BISETTY AND VENKATASUBBA NAIDU NUTHALAPATI

Introduction

Nanotechnology ("nanotech") is the science that deals with the engineering and manipulation of functional materials on an atomic, molecular and supramolecular scale where there is a significant change in the properties from those at larger scale. It encompasses the different scientific phenomena that develop in all the dimensions ranging from atom clusters, molecular aggregates, supramolecular structures, polymers and biomolecules. In other words, nanoscale technology refers to the broad range of research and applications whose common trait is size. In the case of 'nano', it is difficult to distinguish between the science and technology as both feed on each other. Science involves theory and experiment whereas technology involves the development, applications and commercial implications. A generalized description of nanotechnology has been established by the National Nano-technology Initiative, which defines it as a science working in the range of 1 to 100 nanometers. It is a revolutionary science paving the way in almost all fields in the domain of human activity.

Nanotechnology involves two main approaches for the fabrication of materials. The 'bottom-up' approach first leads to the formation of nanostructured building blocks and then assembling them into a final material by principles of molecular recognition. The 'top-down' approach involves the construction of nano-objects from larger entities without atomic-level control. This technique is similar to the approach used by the semiconductor industry for the formation of devices out of an electronic substrate utilizing pattern formation, such as electron beam lithography and pattern transfer processes (reactive ion etching), thereby creating structures at the nanoscale. Analytical science (chemistry) gives a thrust to nanotechnology by coupling it to new-generation analytical tools, such as atomic force microscopy (AFM) and scanning tunneling microscopy (STM) with processes such as electron beam lithography and molecular beam epitaxy, which allows the manipulation of nanostructures with novel phenomena. Thus, analytical chemistry is important in the development of structures in the nano regime and resulting devices. Its highly interdisciplinary nature plays a major role in the advancement of nanotechnology. It helps in establishing the principles and methods in the application of nanotechnology with the unusual properties of nano-materials. These are characterized for their size, morphology and chemical composition using the tools of analytical sciences. In addition, chemical synthesis leads to the fabrication of new nanomaterials with new analytical possibilities.

There are wide applications of nanomaterials in electroanalytical investigations and they have the potential to be used in electrochemical sensors with high sensitivity and selectivity based on different strategies. Electroanalytical analysis based on nanoscience is coupled with the simplicity, speed, high selectivity and sensitivity of electrochemistry with unique properties of nanomaterials to become one of the most exciting areas of research.

In this chapter, we will focus on the revolutionary aspects of nanotechnology and their relevance in analytical sciences within the limits of their practical applications.

1.1.1 Nanotechnology

Nanotechnology is the engineering of functional materials at the molecular scale, which involves the present work and advanced concepts. It is an envisioned ability to fabricate materials using a bottom-up approach with the present era techniques and tools to make complete high-performance products. It has come a long way since its inception and has found potential applications in daily consumer products, appliances and the field of medicine.

In 1959 Richard Feynman, a renowned physicist, envisioned the theoretical capability of nanotechnology in his talk There's plenty of room at the bottom, in which he specified the possibility of manipulating and controlling things on a small scale.

"I want to build a billion tiny factories, models of each other, which are manufacturing simultaneously ... The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom. It is not an attempt to violate any laws; it is something, in principle, that can be done; but in practice, it has not been done because we are too big." Richard Feynman, Nobel Prize winner in physics.

The term "nanotechnology" was popularized by K. Eric Drexler in 1986 in his book "Engines of the Creation: The Coming Era of Nanotechology". He proposed the idea of self- assembly of particles or molecules to build machines a few nanometers wide. Now after nearly 50 years, realizing the dream of the nano-world, nanotechnology has become an accepted concept with the emergence of simple nanoscale technology.

Four generations of nanotechnology products have been identified by Mihail (Mike) Roco of the U.S. National Nanotechnology Initiative with a focus on their manufacturing methods and research.

1. First generation (~2001): passive nanostructures, such as nano-structured coatings, nanoparticle dispersions and bulk materials (metals, polymers and ceramics), with the primary focus on synthesis and control of nanoscale processes along with tools of measurement.

2. Second generation (~2005): active nanostructures (transistors, amplifiers, drugs and chemicals, actuators) with a focus on novel devices and nanobiosensors as the key area of research.

3. Third generation (~2010): three dimensional (3D) nanosystems and systems of nanosystems with various synthesis and assembling techniques with a research focus on heterogeneous nanostructures and supramolecular system engineering.

4. Fourth generation (~2015): heterogeneous molecular nanosystems having a molecule with specific structure and a different role to play. Multiscale self-assembly would lead to nano-archistructures with fundamental new functionalities.

The main question is, what makes nanoparticle so unique? The answer lies in understanding the size, shape and surface topography of a nanoparticle. Particles in the nanometer range exhibit two distinct properties: (i) Laws of classical physics no longer apply below the 50 nm range; therefore, particles are governed by quantum physics. This means as there is a reduction in size, the electronic, optical and magnetic properties are altered as compared to their bulk counterparts. (ii) Ratio between mass and surface area changes i.e. the smaller the size, the greater the surface area available, thereby leading to unique properties of nanomaterials. The availability of the exceptionally large surface area of nanoparticles enables them to react with other substances. In particular, nanoparticles with a crystalline structure have more surface atoms loosely bonded than strongly bonded interior atoms. Thus, there are proportionately more atoms on the surface and fewer in the interior. For example, if the particle consists of 13 atoms, then there will be 12 atom on the surface regardless of which packing scheme has been followed. The fraction of atoms present on the surface (Ps, percentage) can be estimated by a simple relation: Ps = 4N-1/3 x 100, where N is the total number of atoms in a particle. Many potential application areas become prominent in the nano range. Gold, which is chemically inert in the bulk phase, serves as an efficient catalyst at the nanoscale. Thus, the emergence of relevant physicochemical properties is a fundamental requirement for the design of novel materials, thereby unraveling the unknowns of nanotechnology, which stem from quantum and surface phenomena of matter at the nanoscale.

Most of the common nanomaterials can be classified on the basis of their dimensions and orthogonal directions X, Y, Z in which the structural patterns have dimensions LX,Y,Z smaller than the nanoscopic limit L0, which leads to the classical definitions of dimensionality as summarized in Table 1.1. However, occur experimental situations might occur where dimensionality may not be so obviously defined.

Analytical Sciences

Analytical science involves the study of the determination of the composition and inner workings of materials using instrumental techniques. It covers a broad range of sciences, including physics, mathematics, applied computing and instrumentation, with a particular focus on chemistry and biology.

Analytical chemistry plays a crucial role in many areas of science and society. It helps in the designing of new sustainable materials and protocols for synthesis, development of pharmaceuticals and unraveling of complex biological systems by providing sophisticated techniques that make it possible. It has a profound impact on material science, which is dependent on the availability of the analytical tools. Analytical methods are separated into classical (also known as wet chemistry) and instrumental methods. Modern analytical chemistry is dominated by instrumental analysis where the focus is on the single type of instrument. Over the past decade, the scientific and technological interest has shifted from the macroscopic to the nanoscopic size level. With the increasing need for characterizing materials, it is important to analyze local differences in the structure and composition of nano-materials. Before the 1960s, conventional imaging techniques like optical microscopes were available, which could be used for macroscopic objects. Major developments in the analytical chemistry toolbox place after the 1970s where the techniques were started to analyze materials below macroscopic levels. There was a tremendous development in imaging analysis, electron microscopy, beam and probe techniques until 2000. Recent years have seen the emergence of highly sophisticated nanoscopic imaging super resolution techniques, hyperspectral analysis and hyphenated instruments.

Numerous methods and techniques, such as optical spectroscopy, electron microscopy, surface scanning, light scattering, circular dichroism, magnetic resonance, mass spectrometry, X-ray scattering, spectroscopy, zeta-potential measurements, thermal techniques, centrifugation, chromatography and electrophoresis, have been consistently used for evaluating the properties of varied forms of nanomaterials.' The different techniques employed for the characterization of nanoparticles are summarized in Table 1.2.

1.1.2.1 Significance of Nanotechnology in Analytical Sciences

The tools of nanotechnology and nanoscience improve the analytical properties by opening new possibilities of analysis. This is one of the reasons to study, explore and develop nanotechnological tools so that they can be incorporated in analytical sciences. Analytical nanoscience and nanotechnology pave the way by providing promising avenues in the development of analytical science for its two main fields of action: (i) characterization and analysis of nanomaterials; and (ii) use as distinct tools for analysis.

The growing use of some spectrophotometric techniques, such as Raman spectroscopy, near-field microscopy, laser ablation mass spectrometry, ion beams and nano-optical sensing, has made analytical techniques part of the nanoscale revolution. The engineering of nanoparticles has given a thrust and led to the emergence of sophisticated and hyphenated analytical instruments. Analytical processes based on nanotechnology have the capability to exploit the potential applications of nanoparticles (Figure 1.1).

1.2 Facets of Analytical Nanoscience and Nanotechnology

Several possibilities emerge when nanoscience and nanotechnology are introduced into the domain of analytical science. A classification as explained by Vacarcel et al. based on four criterion is depicted in Figure 1.2. >The first criterion considers the type of material to be analyzed, i.e., materials in the macro or micro range and nanomaterials. Nanoparticles like antibody functionalized quantum dots (QDs) could be used in the detection of carcinogenic processes. The second possibility is to use nanostructured materials as analytes. The second criterion is based on the analytical consideration of nanostructured materials as analytes (characterization of nanoparticles) and tools in different processes. To develop new analytical processes or to improve the existing ones, nanomaterials can be employed as analytical tools. Criteria 3 and 4 are based on the exploitation of the properties and sizes of the nanomaterials, leading to three analytical systems related to nanoscience and technology: (i) nanotechnological analytical systems, (ii) nanometric analytical systems, and (iii) analytical nanosystems.

Nanotechnological analytical systems exploit the physicochemical properties of the nanostructured materials, i.e., their use for analytical purposes. Nanometric analytical systems are based on the characteristics or elements of the analytical processes that have nanometer scale flow, for example, nanochip liquid chromatography. They pave the way for miniaturization. The above two systems are integrated in the form of analytical nanosystems where molecular switches could be used for the analytical purpose or carbon nanotubes as electrodes.

1.2.1 Instrumentation

Instrumental analytical chemistry has seen a lot of improvement with the development of sophisticated analytical tools that have the capability of characterizing materials with high complexity and heterogeneity. A number of analytical techniques have the potential to do 2D and 3D imaging, not only at submicroscopic levels but even at nanoscopic (<100 nm) resolution levels. Analytical instruments have developed since the turn of the twentieth century into powerful tools thanks to the advances in the field of analytical chemistry with the breakthrough in size-limited analysis. Most of the major developments in analytical chemistry took place after 1900. It was during this period that most of the instrumental techniques progressively became dominant in the field. In the early 20th century, most of the basic spectroscopic and spectrometric techniques were discovered and were refined in the late 20th century. The first spectroscope for the analysis of atomic emissions dates back to 1859. In 1924, polarography was developed by Heyrovsky and Shikata. The period of 1930s-1950s saw the appearance of analytical instruments for infrared spectroscopy and X-ray fluorescence analysis. Separation techniques were developed between 1975 and 1978, whereas ICP atomic-emission spectrometers came into use in the 1960s-1970s and ICP mass spectrometers in the 1980s. Fourier-transform infrared spectrometers can be dated to the 1970s.

Over a period of time, there has been an incremental advancement and refinement of the analytical techniques, which have developed into versatile and powerful tools for the visualization of structural and compositional heterogeneity, leading to a thriving market for analytical instruments. With the development of hyphenated techniques like field flow fractionation coupled with liquid chromatography-inductively coupled plasma mass spectrometry (FFF/LC-ICPMS), analytical science is making its way more into the applications of nanotechnology. Imaging analysis techniques have evolved from microscopic to mesoscopic and now finally to nanoscale level up to a few nanometers with the highest resolution. With the advent of nano-technology, new imaging tools like scanning tunneling microscope, atomic force microscopy and various other techniques came into existence. Raman spectroscopy got a boost with the use of nanostructures that enhance Raman scattering, giving rise to surface-enhanced Raman spectroscopy (SERS). It can detect single molecules and has an enhancement factor of 10 to 10. SERS substrates prepared using silver nanorods have been used to detect bio-molecules present in low abundance, such as proteins present in the body fluids. This technology has been utilized for the label-free detection of urea and blood plasma in human serum and has a strong capability of becoming the next generation of cancer detection and screening tools. Since SERS substrates can analyze the composition of mixtures at nanoscale, they are found to be beneficial with wide scope for environmental analysis, pharmaceuticals, materials science, forensic science, drug detection, food quality analysis and single algal cell detection. Today, the direct observation and determination of structure is possible with the use of scanning probe microscopes (SPM) and high-resolution transmission electron microscopes (HRTEM) at atomic scale in the order of few tens of picometers.

(Continues...)

---

Excerpted from Advanced Environmental Analysis Volume 1 by Chaudhery Mustansar Hussain, Boris Kharisov. Copyright © 2017 The Royal Society of Chemistry. Excerpted by permission of The Royal Society of Chemistry.
All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
Excerpts are provided by Dial-A-Book Inc. solely for the personal use of visitors to this web site.

---

Table of Contents

Volume 1: Section I: Introduction - Perspective of Analytical Sciences, Synthesis, Properties, Mechanism of Adsorption on Nanomaterials;
Section II: Sample Preparation and Extraction Techniques with Nanomaterials;
Section III: Separation Techniques with Nanomaterials (Chromatography and Membranes Applications of
Nanomaterials);
Section IV:Spectroscopic Techniques with Nanomaterials;
Volume 2: Section V: New trends Nanomaterials for Environmental Analysis (Magnetic Nanomaterials, Lab-on-a-Chip);
Section VI: Nanomaterials for Water Treatment and Purification;
Section VII: Various Important Aspects about Nanomaterials (Toxicity, Risk Assessment, Economic and Legal);
Section VIII: Monitoring and Analysis of Nanomaterials;
Section IX: Conclusions and Future of Environmental Analysis