Where, , 10 #$ % , pHB is the bulk pH, Ψo is the surface potential, NS is the total surface states, Ka & Kb are the dissociation constants of the corresponding reactive sites and VT is the thermal voltage. The is equated and calculated iteratively with the & from the sitebinding model. Bi-section method is adopted to find pHpzc and Ψξ for a particular surface charge density following the below-mentioned relation.