Fig. 4. Zeta potential measurements for h-BN@magnetite prepared using the confined mode of operation of the VFD with the tube rotating at 7.5k rpm and tilted at 45°, with a pure iron rod irradiated using a pulsed laser operating at 1064 nm and 360 mJ, as a function of time, (a) with the concentration of h-BN at 0.1 mg mL⁻¹, and (b) as a function of concentration of h-BN where the processing time was set at 15 min.