EDTA-modified sol-gel synthesis of monoclinic Li2MnO3 nanoparticles as an effective photocatalyst for degradation of organic dyes

Abstract

Monoclinic Li2MnO3 nanostructures were synthesized via modified Pechini sol-gel approach employing the mixture of metal cations, ethylene glycol and different chelating agents. By changing different variables of experimental conditions including molar ratio of M:EG:CA, pH and type of chelating agent can control shape and size of nanostructures. In order to confirmation of crystalline and structural features, XRD, FT-IR and EDX analyses were carried out. SEM and TEM images were taken for morphology investigation. Band-gap of Li2MnO3 nanoparticles calculated by UV–Vis data is 1.76 eV. Moreover, photocatalytic activity of Li2MnO3 nanoparticle was investigated for nano and bulk Li2MnO3 structures in aqueous solution via visible light for degradation of two different dyes of acid red 88 and malachite green. Some effective parameters such as dye type, catalyst dosage, catalyst structure type and cationic additives were evaluated for optimum removal of water pollutant dyes. Cationic additives have different behaviors against cationic and anionic dyes.