Lanthanum cobaltite perovskite supported on zirconia as an efficient heterogeneous catalyst for activating Oxone in...

Zirconia-supported LaCoO₃ perovskite (LaCoO₃/ZrO₂ (LCZ)) is prepared and adopted for the first time as a heterogeneous catalyst for activating Oxone to degrade organic pollutants. The resulting LCZ exhibits a significantly higher surface area (i.e., 10 times) than bulk LaCoO₃ powder as nanoscale LaCoO₃ particles were easily afforded on the surface of ZrO₂ support. As Rhodamine B (RB) decolorization is selected as a model test to evaluate catalytic activity for activating Oxone, LCZ showed a much higher catalytic activity to activate Oxone than LaCoO₃ even though LCZ contained only 12.5wt% of LaCoO₃. LCZ-activated Oxone also remained effective for RB decolorization even in the presence of salts and other organic contaminant. The mechanism of RB decolorization by LCZ-activated Oxone was revealed and involved sulfate radical and other reactive oxygen species. The mechanism of Oxone activation by LCZ could be owing to both La³⁺ and Co³⁺ of LCZ. LCZ was recycled to activate Oxone for RB decolorization over multiple times without loss of catalytic activity. These results demonstrate that LCZ is a promising LaCoO₃-based nanocomposite as a heterogeneous catalyst for activating Oxone to degrade organic pollutants.