Photocatalytically Active Supramolecular Organic-inorganic Magnetic Composites as Efficient Route to Remove β-lactam Antibiotics from Water

Considerable efforts have been made in recent years to identify an optimal treatment method for the removal of antibiotics from wastewaters. A series of supramolecular organic-inorganic magnetic composites containing Zn-modified MgAl LDHs and Cu-phthalocyanine as photosensitizer have been prepared with the scope to β-lactam antibiotics removal from aqueous solutions. The characterization of these materials confirmed the anchorage of Cu-phthalocyanine onto the edges of the LDH lamellae, with a negligible part inserted in the interlayer space. The removal of β-lactam antibiotics occurred via a concerted adsorption and photocatalytic degradation. The efficiency of the composites was depending on i) the LDH: magnetic nanoparticle (MP) ratio, that is strongly correlated to the textural properties of the catalysts, and ii) the phthalocyanine loading in the final composite. A maximum of the efficiency was achieved with a removal of ~93% of antibiotics after 2h of reaction.