You could try methanol as well.

Ethanol

I think you want suspended solution of ZnO NPs. Etahnol, Methanol can be used for the purpose. you can also use DMSO. Instead of NPs solution, term here should be NPs suspension.

Prashant Kumar Kishore Pushparaj Xuhua Wang

thank you so much

Dear Chahra Younsi this interesting question has been frequently discussed on RG. For example, please have a look at the answers to the following closely related questions:

Which solvent is best to disperse zinc oxide nanoparticles?

https://www.researchgate.net/post/Which-solvent-is-best-to-disperse-zincoxide-nanoparticles

and

Which is the best reference solvent for ZnO to perform UV or PL analysis?

https://www.researchgate.net/post/Which-is-the-best-reference-solvent-for-ZnO-to-perform-UV-or-PL-analysis

There are numerous relevant articles in the chemical and materials science literature in which the synthesis and dispersion of ZnO nanoparticles is described. I suggest that you use the "Search" function of RG to find and access other relevant papers. Just search e.g. for the term "dispersion of ZnO nanoparticles" and then click on "Publications". This will provide you with a long list of relevant articles which have been posted on RG, many of them even as public full texts:

https://www.researchgate.net/search.Search.html?type=publication&query=dispersion%20of%20ZnO%20nanoparticles

Good luck with your work!

Frank T. Edelmann thank you sir