Degradation of organic compounds through both radical and nonradical activation of peroxymonosulfate using CoWO4 catalysts

In this study, we synthesized high-efficiency stable CoWO4 nanoparticles that can be used as peroxymonosulfate (PMS) activators for water treatment by adjusting the pH during hydrothermal synthesis. The CoWO4 catalyst synthesized at pH 10 (CoWO4_10), which had the largest surface area and the best charge transfer characteristics, showed the highest degradation efficiency for 4-chlorophenol and the highest stability for metal ion leaching. The first-order degradation rate constant was 10.9 min−1, and the Co and W leaching concentrations after 1 h of catalytic reaction were 1.1 and 4.2 μM, respectively. All the 16 tested organic compounds were rapidly degraded. The degradation performance of CoWO4_10 was 2.4−83.6 times better than those of other Co-based metal oxides. In this regard, the CoWO4_10 can be considered a practical PMS activator. This study provides a simple strategy for the development of highly efficient and stable bimetallic oxides that can be utilized in various fields.