Epitaxial mechanism

For their rich potential in various applications described in the previous section, the synthesis and assembly of various ZnO micro and nanostructures have been extensively explored using both gas-phase and solution-based approaches. The most commonly used gas-phase growth approaches for synthesizing ZnO structures at the nanometer and micrometer scale include physical vapor deposition (40, 41), pulsed laser deposition (42), chemical vapor deposition (43), metal-organic chemical vapor deposition (44), vapor-liquid-solid epitaxial mechanisms (24, 28, 29, 45), and epitaxial electrodeposition (46). In solution-based synthesis approaches, growth methods such as hydrothermal decomposition processes (47, 48) and homogeneous precipitation of ZnO in aqueous solutions (49-51) were pursued. 

Once HAp has been nucleated after OCP is brought in contact with either water or SBF the epitaxial mechanism discussed earlier proceeds quickly and unimpeded (Dorozhkin, 2012). However, nucleation of HAp is the rate-determining step of this reaction and delays conversion of OCP to HAp even in solutions supersaturated with respect to HAp (Ito et al., 2014). 

The adsorption of thiamin, riboflavin, and niacin, components of the B vitamin present in Aspilia Africana extract, was investigated [50]. Those molecules may adsorb through a soft epitaxy mechanism on the metal surface, with accommodation of the molecular backbone in characteristic epitaxial grooves on the metal surface (Fig. 5.3). 

The y-crystal phase is formed under high pressures and moderate cooling rates. It is formed more easily in lower molecular weight polymers or in the presence of an a-olefm comonomer. The y-crystal phase has an orthorhombic unit cell having the following dimensions a = 8.54 A, b = 9.93 A, c = 42.4 A. Lamellae of the y-crystal phase generally nucleate on the a-lamellae by an epitaxial mechanism. ... 

The nucleation of polymer in the presence of NAs is usually due to an epitaxial mechanism. Similar to epitaxial substrates, NAs can change the crystalline structure of polymorphic polymers. From the practical point of view, utilization of appropriate NAs is a convenient and promising approach to... 

Currently, there are four primary processes, epitaxial, mechanical exfoliation, reduced graphene oxide, and chemical vapor deposition (CVD), which have been employed to produce pristine graphene. 

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