I want to know, which one have large surface are, nanoparticles that have cubic morphology or nanoparticles that have spherical morphology, and why?.
the answer is easy: none and both. It depends on the particles!!!!
First, you should talk about specific surface area (i.e. per gram), second about the size of the particles.
For sure you can demonstrate that the sphere is the object that gives the smallest surface over volume ratio per unit volume.
the answer is easy: none and both. It depends on the particles!!!!
First, you should talk about specific surface area (i.e. per gram), second about the size of the particles.
For sure you can demonstrate that the sphere is the object that gives the smallest surface over volume ratio per unit volume.
I agree with Matteo, Sphere naturally has smallest surface to volume ratio, that is the reason rain drops are spherical.
Thanks for the answer. I am also think that, but from the laws of surface area of spherical = 4πr2 while cubic = 6l2 if l=r, 4π > 6, so spherical is higher.If we look to number of edges, cubic is high.
Please, do you have evidence?
I guess that the relationship between Surface area (m2/g) and particle size is only follow for very low S.S. (very high particle size). At least in typical powder solids (I mostly have experience with oxides) if you go above 10-20 m2/g, the particle size/shape would predict S.S. exceeding the experimental result by a minimum factor of 2. Attachement among particles is as important as particle size to interpret surface area in a significant number of solids.
@ Hani but Sphere volume is 4/3 pi r3 and cube has a3 (a=r) and 4/3 Pi r3 >> a3. Hence, again matteo leoni is coorect. always consider specific surface are with respect to volume.
Well , thermodynamically speaking, the sphere has the lowest surface area in comparison to cubes, squares, rectangular ,triangle and so on. Because the work or energy required to form the sphere is lower than that required to form other geometries for the same quantity of the material. dW (Work) directly proportional with dA(Area). Accordingly, the bubbles, the cavities and the liquid droplets are spherical.
It is correct, but surface area depends on the porosity and its size, between more porosity in the material, more surface area.
To Dr.Hilal,
But I read in Z.L.Wang book under title " characterization of nanophase" page 58 that pt nanocrustals with cubic morphology shows transformation to spherical when temperature increase to 500C. The study was taken by in-situ TEM.
So, how can you explain this information together?
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