Figure 1.

Surface engineering of particle-based dispersants. A) Schematic representation of surface modifications performed. Commercially available (as-produced) CB is washed with 0.1 M HCl to remove impurities and then either annealed to a more hydrophobic version (left) or functionalized using diazonium chemistry to a more hydrophilic form (right). B) Change in zeta potential as a function of pH, at an ionic strength of approximately 165 mM. C) Determination of the pK_a value distribution by acid–base titration of the functionalized CB as compared to the precursor particles. D) Probable side reaction is the self-polymerization of the diazonium intermediate leading to greater than monolayer coverage of benzoic acid groups.