How can we efficiently dry metallic nanoparticles

[nadaben]

hello everyone

i wonder if someone can help me to dry completely metallic nanoparticles synthesized in water
while maintaining their shape (without aggregation).or if there is a way to synthesize them directly in organic phase

 

[Paul Colby]

Heat in a vacuum?

 

[nadaben]

normally metallic nanoparticles are sensitive to higher temperatures.. i tried to dry them in rotary evaporator but they remains sticked in the vial

 

[Paul Colby]

It's about vapor pressure. If they are metallic they can survive some temperature elevation and it may not take much. Sticking to the vial may be a function of what is in solution with them and or something as simple a Van der Waals forces.

Another approach might be the use of a desiccant.

 

[Nidum]

DIY miniature fluidised bed . Air blown . Optionally other gasses or solvent vapour .

Basically blow air the wrong way through filter membrane .

 

[nadaben]

The nanoparticles are prepared in water ! I have no other products in the solution.. the goal is to dry and redissolve them in organic solvents so I must avoid agglomerating them while drying

 

[Paul Colby]

I don't claim to be even mildly familiar with nano-particles (outside of some experience with polystyrene micro spheres suspended in water). Would it be possible to add the aqueous suspension into your organic solvent then remove the excess water?

 

[TeethWhitener]

First question: what metal?
Second question: do you not want to cap the NPs with a surfactant?

hello everyone

i wonder if someone can help me to dry completely metallic nanoparticles synthesized in water
while maintaining their shape (without aggregation).or if there is a way to synthesize them directly in organic phase

 

[nadaben]

Even if we add the organic solvent nanoparticles have an affinity to water so they remain in the aqueous phase
Metal are gold or silver...what is the role of the surfactant? Is it to transfer them to the organic phase? In this case I've tried this method but it doesn't work for my solvent( chlorobenzene) and for bigger sizes of nanoparticles

 

[TeethWhitener]

So you don't use something like a long-chain alkylthiol to moderate AuNP growth?

 

[nadaben]

No actually i didn't try! Do you have references in this way?

 

[TeethWhitener]

https://gmwgroup.harvard.edu/pubs/pdf/508.pdf
This is one of the early papers from the Whitesides group. They specialized in gold-thiol SAMs for a while back in the 90s-2000s.

 

[nadaben]

Thank u so much ! It's a very important work .. i should look for its details ! If u have any other ideas or references please share