Use capping agents such as Oleic acid or use some surfactants such as CTAB during synthesis.

Or use charged polymers to prevent agglomeration

Rohit Kumar Charge (electrostatic) or steric stabilization. Keep the system wet and never dry. For more information, see this webinar (free registration required):

Dispersion and nanotechnology

https://www.malvernpanalytical.com/en/learn/events-and-training/webinars/W190528DispNanoMat

Here is a link to how we do it:

https://s3.amazonaws.com/video.sono-tek.com/mp4/SonicSyringe-Ultrasonic-Dispersion-Syringe-Pump.mp4

Maybe surface modifications is a good direction.

Reducing the aggregation or agglomeration of nanoparticles can be achieved through some strategies:-

1. Surface modification.

2. Stabilizing agents.

3. pH adjustment.

4. Ultrasonication.