Nanochemistry/nanotechnology

Keywords Nanochemistry Nanotechnology Nanotoxicology Nanoparticles Nanostructures, micrographene sheef ... 

The condition, if all else is constant , suggests the question what if other entities are present This is especially important in the field of nanochemistry/nanotechnology, where metal-containing nanoparticles usually are covered with small molecules to prevent them from agglomerating instead of staying separate. Typically, a surfactant is applied to cover the nanoparticles as they are being formed. 

The study of principles relevant to building nanoscale structures of, for example, 1-100 nm in size has recently been referred to as nanoscience, and it is expected that methods for the fabrication of nanostructures will evolve into nanotechnologies. The present approach toward a nanochemistry is of more fundamental character since it is restricted to single molecules of a few nm in size or even smaller and focuses on the molecular pattern. 

Pores are found in many solids and the term porosity is often used quite arbitrarily to describe many different properties of such materials. Occasionally, it is used to indicate the mere presence of pores in a material, sometimes as a measure for the size of the pores, and often as a measure for the amount of pores present in a material. The latter is closest to its physical definition. The porosity of a material is defined as the ratio between the pore volume of a particle and its total volume (pore volume + volume of solid) [1]. A certain porosity is a common feature of most heterogeneous catalysts. The pores are either formed by voids between small aggregated particles (textural porosity) or they are intrinsic structural features of the materials (structural porosity). According to the IUPAC notation, porous materials are classified with respect to their sizes into three groups microporous, mesoporous, and macroporous materials [2], Microporous materials have pores with diameters < 2 nm, mesoporous materials have pore diameters between 2 and 50 nm, and macroporous materials have pore diameters > 50 nm. Nowadays, some authors use the term nanoporosity which, however, has no clear definition but is typically used in combination with nanotechnology and nanochemistry for materials with pore sizes in the nanometer range, i.e., 0.1 to 100 nm. Nanoporous could thus mean everything from microporous to macroporous. 

What may be a brave new world with which to inform and challenge our students The nanoworld. This is a real and present challenge to provide the best information possible. What this means is that we need to do our best at the time, to incorporate the principles that seem to dictate the behavior of nanomaterials into our physical chemistry courses. (Notice in this discussion other than right now the word nanotechnology will not be mentioned.) Nanoscience and nanochemistry are phrases we should be using to discuss this area. Here again we as chemists are our own worst enemies by not presenting... 

Ozin GA, Arsenault AC. Nanochemistry A Chemical Approach to Nanotechnology. Royal Society of Chemistry Cambridge, 2005. 

Liliya Bazylak, PhD, is Senior Staff Scientist in the Rhysical-Chemistry of Combustible Minerals Department at the Institute of Rhysical-Organic Chemistry and Coal Chemistry at the National Academy of Sciences of Ukraine in Lviv. She is the author of more than 200 publications. Her scientific interests include physical chemistry, nanochemistry and nanotechnologies, and also chemistry of high molecular compounds. 

Nanochemistry, nanophysics, and nanotechnology have been the source of a number of nano objects, inducing an increase of new proposals in the last 15 or 20 years. The peculiar properties ascribed to the dimension and shape, which is thoroughly discussed in the following chapters, specifically in Chap. 6, render them of outstanding interest in view of satisfaction of some of the most important peculiarities sought in a modifier. However, note that the term nano , so often found in the scientific literature, does not always actually refer to dimensions spontaneously quantified by nanometer units. This is definitely not a semantic issue, since only true nano dimensions ascribe the relevant objects peculiar properties. 

J. W. Steed, D. R. Turner, and K. Wallace, Core Concepts in Supramolecular Chemistry and Nanochemistry From Supramolecules to Nanotechnology, Wiley-VCH Verlag GmbH, Weinheim, 2007. 

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