Confined heterogeneous catalysis by boron nitride-Co3O4 nanosheet cluster for peroxymonosulfate oxidation toward ranitidine removal

Peroxymonosulfate (PMS) induced advanced oxidation processes hold great promise for heterogeneous oxidation reactions. In this study, boron nitride (BN)-Co3O4 nanosheet cluster (NC) was fabricated to facilitate PMS activation with a nanoconfined heterogeneous catalysis effect for the rapid removal of ranitidine (RAN) under mild conditions. The obtained BN-Co3O4 NC cluster exhibited efficient catalysis performance with a 99.5% removal efficiency for ranitidine in 5 min, and meanwhile this novel catalyst could be applied under a wide pH range (pH: 3-9) with still high degradation efficiencies. The porous structure of BN-Co3O4 NC provided a large number of channels for RAN and PMS molecules to enter the catalyst's inner confinement space, resulting in a remarkable enhancement of catalytic performance. The kinetic rate constant for RAN degradation by the BN-Co3O4 NC/PMS system with 3-33 fold less catalyst dosage is much larger (1.58-213 fold) compared with the state-of-the-art. PMS activation by BN-Co3O4 NC was mainly due to the pathway of reduction via active radicals. Density functional theory calculations specified that the concomitant active radicals such as center dot OH and SO4 center dot- were mainly derived from PMS activation via O-O bond cleavage. This work provides a new perspective for regulating the structure of Co3O4 and elucidating the mechanism of PMS-induced heterogeneous catalytic oxidation.

Automated summary

In this study, boron nitride (BN)-Co3O4 nanosheet cluster (NC) was fabricated to facilitate PMS activation for the rapid removal of ranitidine (RAN). The BN-Co3O4 NC showed highly efficient catalysis performance and could be applied in a wide pH range. The porous structure of BN-Co3O4 NC enhanced the catalytic performance by providing more channels for RAN and PMS molecules. PMS activation by BN-Co3O4 NC was mainly achieved through reduction via active radicals.