Dear Mohammad Sadegh Aghajanzadeh, you can use a surfactant, example isopropyl alcohol. Please check the following document. My Regards

https://doi.org/10.1016/B978-008044528-1.50002-6

Dear Mohammad Sadegh Aghajanzadeh, you can use a surfactant, example isopropyl alcohol. Please check the following document. My Regards

https://doi.org/10.1016/B978-008044528-1.50002-6

Dear Mohammad,

Silica nanofluids have been prepared by Rosa et al. dispersing the nanoparticles in distilled water using an ultrasonic probe, which has proved to be the most effective system and gave the best results, according to her, when compared with previous works. Results were obtained concerning the influence of the solid content, pH and salt concentration on the zeta potential, electrical double layer, viscosity, elastic and viscous moduli, particle size and light backscattering. Despite the agglomeration due to high concentration, nanofluids with low viscosity and behaving like liquid were prepared at 20% of mass with the ultrasonic treatment. The pH of the medium can be used to control the stability, since the nanofluids are more stable under basic conditions far from the isoelectric point (IEP) and settle at pH = 2. Therefore, stable nanofluids for at least 48 h, with high solid content, can be prepared at high pH value (pH > 7) due to the electrostatic repulsion between particles.

For more information, I will mention the link here.

Thank you.

Article Characterization of silica–water nanofluids dispersed with a...

Hi ;

The solubility of silica is very low in neutral solution but increases with pH. Solubility is significant above pH = 10. Dissociation becomes important at high pH's, leading to an increase in silica dissolution by shifting equilibrium.

An improvement in the dispersion of the silica can also be obtained by adding a surfactant. The combination of ultrasound with the presence of a surfactant disaggregates and facilitates the breaking up of silica aggregates in water.

With my best regards