Efficient catalytic degradation of carbamazepine using single-atom Ru-NiFe-LDH: Role of 1O2 and selective degradation

The targeted elimination of stubborn organic pollutants is crucial for human health and ecosystem well-being. Thanks to its exceptional efficiency and other benefits, peroxymonosulfate offers extensive potential for water treatment. However, realizing the practical application of this technology hinges on creating a high-efficiency catalyst. This study presents the fabrication of a monoatomic Ru catalyst through a straightforward hydrothermal approach. Synchrotron radiation and spherical electron microscopy were used to confirm the binding of monoatomic Ru to the NiFe-LDH (Layered Double Hydroxide, LDH) surface. Using a catalyst containing 0.77 wt% of single-atom Ru, 20 mg/L of Carbamazepine (CBZ) could be eliminated within 25 mins. With this, an impressive pseudo-first-order reaction rate constant of 0.118 min−1 was attained. The feasibility of the catalyst was evaluated in a column experimental reactor. The removal rate of 0.5 g of catalyst in wastewater containing 20 mg/L CBZ reached 100 %, demonstrating sustained operation for 720 mins. Ru-LDH/PMS system preferentially degrades carbamazepine, ciprofloxacin and other pollutants. This may be related to the structure and HOMO value of the pollutants and the active factors stimulated by Ru-LDH. Through a range of probe reactions and spectral analysis, it was determined that 1O2 played a pivotal role in pollutant degradation, closely linked to the presence of Ru.