Influence of plasma treatment on microstructures and acid-base surface energetics of nanostructured carbon blacks: N₂ plasma environment

In this work, the effect of N₂ plasma treatment generated by radiofrequency was investigated in the context of surface and microstructure characteristics of carbon blacks. XRD measurements revealed that the interlayer spacing, d₀₀₂ and crystalline size along the c axis, L_C, decrease with plasma treatment, which can result in the removal from weak or unstable microstructures of carbons. In this work, the determination of electron-acceptor (γ_S⁺ and -donor (γ_S^-) parameters of the surface free energy of a solid was proposed by the polar testing liquids using a water, diiodomethane, and ethylene glycol. It was clear that the major obvious improvement of the treatment is in the London dispersive component of the surface free energy of carbon blacks. And both γ_S⁺ and γ_S^- for the specific component also increased with increasing treatment time, resulting in improvement in the surface functional groups of the carbon blacks studied, together with increases in acidic and basic surface functional groups and ion-exchange properties.