Adeola Abraham Fadahunsi

We need a lot more information to be able to answer your question.

• What is your material and how is it made/synthesized?
• What were the filtration conditions you used for the liquids you employed?
• Why did you dilute the sample? And why did you use DI water and not the 'mother liquor'? Have you diluted out the stabilizer(s)?
• Why do you need/want to sonicate?
• Do you know the approximate size?
• Why can't 0.4 - 0.6 be the natural/correct PDI of your preparation?

In terms of answering your question absolutely specifically, you reduce the PDI of a system by removal of the large and small fraction concentrating the population in a narrow band.

Dear all, may be fractionation is an option to give it a try. Please check the following document. My Regards

https://doi.org/10.3389/fchem.2015.00045

@ Alan F Rawle Alaa A. A Aljabali Abdelkader BOUAZIZ My starting material is NbAl2C (MAX) 2D material. I etched with HF and exfoliated it with TPAOH (Tetrapropylammoniumhydroxide) to get Nb2C (an MXENE which is my product of interest). The as-prepared Nb2C was washed with water and ethanol in a centrifuge, resuspended in DI water, and measured the size on DLS. However, the size was 300nm, while I was expecting an approximate size of 120nm. I diluted my DLS sample some more thinking perhaps it was too concentrated, but there was no change. Then I tried to sonicate, and re-measure I got a much lower size, but the PDI is large. I only want the 100 nm-sized particles.

Adeola Abraham Fadahunsi

Centrifuge and remove the supernatant at some appropriate time. Will need trials.

Dear all, I think the etching time and/way are not well selected, i.e., charges are not enough to produce fine dispersion. Please check the following document. My Regards

https://doi.org/10.1002/admi.201802004

Alan F Rawle Abdelkader BOUAZIZ Thanks for the insight. I will give it a try.