Even though Co3O4 is the most conventional heterogeneous catalyst for activating peroxymonosulfate (PMS), Co3O4 nanoparticles (NPs) aggregate severely, especially in water, losing their catalytic activities. In the present study, an electrospinning technique is employed to prepare Co3O4 nanofiber (CONF), in which severe aggregation of Co3O4 NPs can be prevented as Co3O4 NPs are specifically configured into fibers, rendering a much higher surface area and porosity than conventional Co3O4 NPs. When decolorization of Acid Red 27 (AR) is employed as a model test for PMS activation, CONF exhibits considerably higher catalytic activities than the commercial Co3O4 NPs for activating PMS to decolorize AR completely in 15 min with a rate constant of 0.210 min−1. The Ea of AR decolorization by CONF-activated PMS is 43.5 kJ/mol, which is also lower than several reported studies. CONF can be also re-used to activate PMS over multiple cycles. AR degradation is confirmed to involve with sulfate radicals via examining effects of radical scavengers and Electron Paramagnetic Resonance analysis. The findings obtained in this study successfully demonstrate that the electrospinning technique can be utilized to prepare nanoscale fibrous Co3O4 with improved physical and chemical properties for catalytic advanced oxidation applications
