Preference for dispersion: 1. Ultrasonic probe sonicator is best dispersion of nanoparticles/nanowire. 2. ultrasonic bath 3. magnetic stirrer, In case of magnetic stirring the probability of particle agglomeration is high compare to above two methods. 

thanks dear Mr B Krishna

I have a cleaner sonicator (50 HZ, 170 W), is it suitable for this purpose?

If possible use both cleaner sonicator and magnetic stirrer. For the conformation of dispersion of MWCNT, go for DLS (dynamic light scattering) to see the distribution and size of MWCNT.

Ultrasonic bath is an efficient homogenizing  tool    which reduce hard particles to small sizes and hence increase the particle surface area. Ultrasonic bath  is also  improve   dispersion, uniformity  and stability  of particles. Benefits of ultrasonic bath  aren't available with other styles of magnetic  stirrers. Several methods  for producing functionalize CNTs have been reported. I wish the attached link is  useful and help you . http://cdn.intechopen.com/pdfs/17292.pdf

Thanks dear D.R. Alshamsi for your  valuable comment.

Dear  Krishna

Do you mean that use of both cleaner sonicator and magnetic stirrer at the same time or step by step?

Step by step.

I agree with Dr. Hassan in answering the question