Ultrathin CoO@NC nanosheets derived from NaBH4-treated ZIF-67 for ofloxacin degradation

Modulating the morphology of precursor can effectively adjust the property of derived composite. Herein, after post-treated by NaBH4, a layered ZIF-67 precursor was endowed with high porosities, partially delaminated and curled layers. With this material as precursor, the pyrolysis composite, P-CoO@NC, exhibits a morphology of ultrathin N-doped carbon (NC) nanosheets coupled with highly dispersed CoO nanoparticles. This composite can active peroxymonosulfate (PMS) and degrade ofloxacin (OFL) with an efficiency of 96.8 % (10 min). After recycling for five times, the degradation efficiency can still reach 82.5 %, which demonstrates its catalytic activity and stability as an advance oxidation process (AOP) catalyst. As confirmed by related experiments, both radical (SO4— and O2—) and non-radical (1O2) pathways take part in OFL degradation in P-CoO@NC system. Overall, this work demonstrates a specific role of NaBH4 in modulating MOF precursor and further the property of derived composite.