Nanomaterial corrosion

XPS has been used in almost every area in which the properties of surfaces are important. The most prominent areas can be deduced from conferences on surface analysis, especially from ECASIA, which is held every two years. These areas are adhesion, biomaterials, catalysis, ceramics and glasses, corrosion, environmental problems, magnetic materials, metals, micro- and optoelectronics, nanomaterials, polymers and composite materials, superconductors, thin films and coatings, and tribology and wear. The contributions to these conferences are also representative of actual surface-analytical problems and studies [2.33 a,b]. A few examples from the areas mentioned above are given below more comprehensive discussions of the applications of XPS are given elsewhere [1.1,1.3-1.9, 2.34—2.39]. 

The book may be of interest for the specialists dealing with the production of high-energy compounds (gas generators for air-bags, explosives, propellants, and pyrotechnics), nanomaterials, polymers, fibers, superelectrophiles, nonlinear optical materials, dyes (including fluorescent and cyanine dyes), and inhibitors of metal corrosion. It is also useful for people working in pharmaceutical industry. 

While these techniques are widely used, they do not provide sufficient purity. Liquid phase purification is not an environmentally friendly process and requires corrosion-resistant equipment, as well as costly waste disposal processes. Alternative dry chemistry approaches, such as catalyst-assisted oxidation or ozone-eiuiched air oxidation, also require the use of aggressive substances or supplementary catalysts, which result in an additional contamination. Moreover, in many previous studies trial and error rather than insight and theory approaches have been applied. As a result, a lack of understanding and limited process control often lead to extensive sample losses of up to 90%. Because oxidation in air would be a controllable and enviromnentaUy friendly process, selective purification of carbon nanomaterials, such as CNT and ND, in air is very attractive. In contrast to current purification techniques, air oxidation does not require the use of toxic or aggressive chemicals, catalysts, or inhibitors and opens avenues for numerous new applications of carbon nanomaterials. 

In general, vapor deposition methods refer to any process in which materials in a vapor state are condensed on a surface to form a solid-phase. These processes are normally used to form coatings to alter the mechanical, electrical, thermal, optical, corrosion resistance and wear resistance properties of various substrates. Recently, vapor deposition methods have been widely explored to fabricate various nanomaterials such as NS-T102. Vapor deposition processes usually take place in a vacuum chamber. If no chemical reaction occurs, this process is called physical vapor deposition (PVD) otherwise, it is called chemical vapor deposition (CVD). In CVD processes, thermal energy heats the gases in the coating chamber and drives the deposition reaction. 

Nano-clay incorporated polymer coatings are important for modifying properties of surfaces. Nano-clay incorporated thermoset polymer nanocoatings exhibit superior properties such as super-hydrophobicity, improved wettability, excellent resistance to chemicals, corrosion resistance, improved weather resistance, better abrasion resistance, improved barrier properties and resistance to impact, scratches, etc. [116]. The parameters such as dipping time, temperature, nature of surfactant, and purity of nanomaterials decides the coating thickness. Clay-epoxy coating... 

Recently, the research on exploring the use of carbon nanomaterials as metal-free catalysts has been one of the major subjects for the fuel cell research. Owing to their wide availability, environmental acceptability, corrosion resistance, and unique surface and bulk properties, carbon nanomaterials are ideal candidates for metal-free ORR catalysts. In this context, we have demonstrated that vertically aligned nitrogen-doped carbon nanotube (VA-NCNTs) array exhibited three times higher ORR electrocatalytic activity and better long-term operation durability... 

Despite different definitions, it can be observed that corrosion is basically the result of interaction between materials and their environment. Up to the 1960s, the term corrosion was restricted only to metals and their alloys and it did not incorporate ceramics, polymers, composites and semiconductors in its regime. The term corrosion now encompasses all types of natural and man-made materials including biomaterials and nanomaterials, and it is not confined to metals and alloys alone. The scope of corrosion is consistent with the revolutionary changes in materials development witnessed in recent years. 

Jiang X, Jiang YB, Liu N, Xu H, Rathod S, et al (2011), Controlled Release from Core-Shell Nanoporous Silica Particles for Corrosion Inhibition of Aluminum Alloys Journal of Nanomaterials, Article ID 760237, 10 pages. 

Corrosion protection and control using nanomaterials Edited by V. S. Saji and R. Cook... 

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