What is nucleation energy? If I am making hybrid nanoparticles (metal oxide/metal), the reaction mixer contains both precursors (metal and metal oxide) and allowing to grow both nanocrystals simultaneously to make hybrid nanoparticles. Which nanoparticle can grow faster than the other? Does nucleation energy determine growth rate of nanoparticles?
Nucleation energy is the required amount of energy for any chemical reaction to happen.
Nucleation specifically changes the phase of any system, whereas growth rate is controlled by various parameters like heat, pressure etc. When a NP nucleates, then these external physical parameters determines its growth.
The Gibbs energy (delta G) of nucleation of a new phase with homogeneous nucleation has three components: bulk, surface, and elastic deformation energy during the structural change of solids. The surface energy acts as a potential barrier to condensation.
The kinetics of formation of a new phase is determined by two stages: the rate of formation of nucleus centers and rate of delivery of the substance to the nucleation center, which ensures the formation of a stable nucleus. . The rate of formation of condensation centers is proportional to the probability of its nucleation.
I =A exp(- delta G/RT). (1)
The rate of delivery of a substance to the nucleation center is proportional to the probability of the “survival” of the nuclei that have emerged
U = B exp (- E/RT) (2)
E - activation energy of a viscous flow or energy of transition of a substance to the surface of a nucleus. A, B - proportionality coefficients.
The overall rate of formation of centers of condensation nuclei is proportional to the product of the above probabilities.
As can be seen from equation (1), the growth rate of the nucleus of the nanoparticles depends on the Gibbs energy.
Thank you Yuri Mirgorod, Could you suggest me further useful reading?
https://www.mpikg.mpg.de/886735/Nucleationlecture.pdf
A. A. Bochkarev, V. I. Polyakova. Processes of Formation of Micro -and Nanodispersed
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