Fig. 6From: Hollow and oval-configured ultrafine Co3O4 as a highly-efficient activator of monopersulfate for catalytic elimination of Azorubin S(a) recyclability of HOCO over multiple ARS degradation cycles; (b) XRD pattern of the used HOCO; (c) influence of radical scavengers on ARS elimination using HOCO + MPS; (d) EPR analysis. (Reaction conditions: HOCO = MPS: 100 mg L− 1, T = 30 °C)Back to article page