Heterogenization of water-soluble porphyrins in Ti/TiO2 nanotubes electrodes: experimental and theoretical insights for atrazine degradation

Pollutant degradation has been a very important topic in environmental research. The present paper presents an approach to degrade atrazine, an environmentally harmful herbicide that has been widely used in the agriculture industry. Ti/TiO2 nanotube electrodes modified by porphyrins were prepared for photolysis, photocatalysis, and photoelectrocatalysis (PEC) applications. Manganese- and free base porphyrin were studied, and it was possible to verify the kinetic model more suitable for each system. Unfortunately, Mn-porphyrins had an inhibitory effect on the ATZ degradation activity by Ti/TiO2 nanotube electrodes. Although the Ti/TiO2-free base porphyrin under the PEC experiment (using surface water from a Brazilian river) did not lead to the best degradation system, we could verify the formed products, which have been not described for other porphyrin-mediated atrazine degradation, are equal or more toxic than the original atrazine. We highlight the importance of verifying the products formed in the degradation systems and determining their toxicities.

Automated summary

This paper presents an approach to degrade atrazine, an environmentally harmful herbicide. Different types of porphyrins were studied and their effects on degradation were evaluated. The formed products were found to be equally or more toxic than the original atrazine, highlighting the importance of verifying the products and determining their toxicities.