May I ask you about the difference between porous graphitic carbon (PGC) and graphitized carbon black (GCB) in terms of surface properties, retention mechanisms, and redox potentials?
I don't think the two below references get you all you want but they should give you some of what you are looking for. Good luck.
Article Structure and performance of porous graphitic carbon in liqu...
By contrast, at the colloidal level, PGC and GCB are very different: where GCB consists of loosely aggregated colloidal units having only weak Van der Waals bonding between them. PGC has a strong sponge-like structure, capable of withstanding considerable shearing forces such as those met with in high-performance liquid chromatography (HPLC).