Gibbs-Thomson effects - ULiege · Gibbs, Thomson and Thomson Josiah Willard Gibbs 1839-1903...
Transcript of Gibbs-Thomson effects - ULiege · Gibbs, Thomson and Thomson Josiah Willard Gibbs 1839-1903...
Gibbs-Thomson effects
November 2014
Gibbs-Thomson effects
Small crystals melt at a lower temperature, which is the reason why ice cream gets crunchier with time.
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Melting of metal nanoparticles
Thermochimica Acta 463 (2007) 32–40 Phys. Rev. A 13, 2287–2298 (1976)
Au Al
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A related but simpler problem
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Gibbs-Thomson
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Gibbs, Thomson and Thomson
Josiah Willard Gibbs 1839-1903
Chemical potential
(1st PhD in Eng. in the US)
Joseph John « J.J. » Thomson 1856-1940
One of the fathers of
atomic physics (discoverer of the electron)
William Thomson (1st baron Kelvin) 1824-1907
The Joules-Thomson effect
etc. etc. etc. 6
Lamellar crystals in polymers
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Gibbs-Thomson for lamellar crystals
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Melting in nanopores
J. Chem. Phys. 93, 9002 (1990); The melting behavior of organic materials confined in
porous solids 9
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As an exercise…
11 Appl. Phys. Lett. 85, 5337 (2004)
Derive the Gibbs-Thomson relation in the case of a cylindrical nanowire
Liquid-vapor equilibria
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William Thomson (1st baron Kelvin) 1824-1907
What if there is no wetting layer?
A small and a large droplets lie on a fiber.
How does the system evolve?
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Ostwald ripening of metal nanoparticles: case of Ni in presence of CO
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16 Supported catalysts with monodispersed particles are more stable in time
Effect of size on solubility
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Stress generationby salt crystallization
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Laplace pressure 2γ/R
Laplace pressure γ/R + compressive stress σr
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Wheathering by salt crystallization
Honeycomb weathering (tafoni)
20 http://en.wikipedia.org/wiki/Weathering#Salt-crystal_growth
The mechanism is still unclear…
Capillary condensation in nanopores: Kelvin’s equation with a negative curvature
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Surface phenomena
Pore-filling phenomena
Chemical potential
Adsorption and desorption
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Adsorption
Desorption
Richard Adolf Zsigmondy 1865-1929
Nobel Prize in Chemistry 1925