Molecular Descriptor for Catalytic Direct Oxidative Transfer Process Based on Thermodynamic State Changes during Reactions

The direct oxidative transfer process (DOTP) in heterogeneous catalytic persulfate oxidation (HCPO) systems has gained increasing attention. In this process, the reaction rate is linked to pollutant properties, and identifying this correlation through descriptors offers insights into reaction mechanisms and water treatment strategies. However, most of the existing descriptors are based on static molecular properties and show limited correlation with reactivity and mechanisms. In this work, we proposed descriptors based on molecular thermodynamic state changes during reactions. The descriptor reflecting the energy change associated with losing two electrons and one proton (ΔE2e1p) proves most effective, exhibiting a strong correlation (R2 = 0.938) with the reaction rate of phenolic and amine pollutants in carbon nanotube/peroxydisulfate system. Multiscale characterizations elucidate the DOTP mechanism in this system, explaining ΔE2e1p's superior performance and highlighting the critical role of pollutant proton transfer. A comprehensive analysis of the new and existing descriptors reveals the limitations of previous descriptors and the influence of the substrate range on applicability. Additionally, ΔE2e1p demonstrates broad applicability across diverse HCPO systems and practicality in real water matrices. This work provides insights for developing molecular descriptors for catalytic oxidation processes.