I have prepared a material which is having dimension less than 100 nm s. After a few days, there was an agglomeration and it formed grains and the size exceeded 100 nm s. Will that not be considered as a nanomaterial ?
Check if agglomeration is reversible. The easiest way is to sonicate the sample and check if the original distribution was restored.
In between, most of nanoparticle suspensions is unstable with respect to agglomeration.
What do u mean by particle will settle down in solvent which can be optimally used?
Please explain?@Swati Jain
Ya. But my material will not dissolve completely in any of the solvent to sonicate it.Then how Sir?
So as u said I have to sonicate it and check SEM whether the original distribution is restored ?@Dmytro Volkov
Yes, while you have agglomeration, it does not mean that the original particles got fused together upon contact (ripening). You just might have to stabilize your suspension with surfactant or any other available technique to prevent agglomeration or switch to a different supernatant.
try a stabilizer or any viscosity improving agent in optimal(low) concentrations to prevent the aggregation. As Dmytro said, surfactant will be very helpful if you are not going to dry the product.
I guess the answer depends largely on you and not on the actual size of the specimen. In your case you have a problem of agglomeration (probably due to a very low zeta potential). Stabilizing the system, as suggested, can help you keeping your particle separated. But do you really need that? I mean, the size of particles is usually reduced in the nano-range to see new (or enhanced) properties with respect to the bulk or coarse grain counterpart. In some other cases the smaller size can help (e.g. in the bio field) to have small enough and smart carriers e.g. for drugs. So one of those happens, your materials can still be considered as a "nanomaterial" and what you have is simply a set of non-stabilised clusters
Thank u! But what happens if I dry the product after adding surfactant?@Natarajan
Thank u Sir! So this specific surface area has no relation with Nano Material's size?@Matteo Leoni
Dear Satish,
There was no use of surfactant if you going to use your product as solid/powder form. it required only if your product has to be kept in liquid form for a period of time. That would give stability to your suspension. The drying after addition of surfactant will give slurry like product. the product will not be like free flow powder. i like to know, why you sticking to the specific surface area, would you like to interpret anything using that?
Particles up to 100 nm dimensions are say basic building block as nano-materials but assume same size of particle is in physical contact with it then such agglomerate particle size exceeds 100 nm. The specific surface area measurements is one of the tool to characterize the size of individual and agglomerate particles. I feel Dynamic Light Scattering (DLS) may be another concept like specific surface area to determine a nano material particle or agglomerate size estimations.
@Satish: I doubt e.g. a 0.01 m^2/g surface area catalyst will be that useful. Remember always to frame your question well, i.e. why you need the information for. Otherwise you are likely to get a lot of answers, but a few completely useful ones as each of us can thing of a different aspect of the problem or different issue you might have. Surface area can be important (e.g. in catalysis), but can be tricky (e.g. total one or accessible one?). From the area alone it is hard to get a definitive information on the size (you can have several distributions giving the same surface area, plus there is the problem e.g. of the contact area. Usually the specific area information is obtained from BET measurement. If you do things properly you can try to estimate the size from the isotherms.
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Materials Science
- Materials
- Nanomaterials