Facile synthesis of Mesoporous Sm@ POA/TP and POA/TP nanocomposites with excellent performance for the photocatalytic degradation of MB and MG dyes

A highly efficient and recyclable catalysts, mesoporous poly o-anisidine titanium phosphate (POA-TP) and Sm co-doped POA-TP have been synthesized by chemical in situ polymerization in micellar media. Mesoporous nanocomposites of POA-TP and Sm@ POA-TP have been characterized by instrumental techniques such as FTIR, XRD, TGA-DTA, SEM, TEM, PL, electron-paramagnetic resonance (EPR) spectroscopies & UV-vis diffuse reflectance spectroscopy (DRS) and their photocatalytic performance were investigated based on the degradation of methylene blue (MB) and malachite green (MG) dyes. The optical properties revealed that the band gap of Sm@POA-TP was reduced from 3.76 eV (POA-TP) to 3.70 eV (Sm@POA-TP) due to the presence of new donor energy levels with Sm3+ loading. The experimental results indicated that the enhanced photo-catalytic performance with Sm@POA-TP could be attributed to the increased optical absorption and efficient separation and migration of photo-produced charge carriers with decreasing the recombination of electrons-holes creating from doping effects. Cyclic voltammetry study was employed to investigate the redox behaviors and the current producing ability of the materials. The distribution coefficient values were used as the basis for the separation and determination of metals in water samples. The analytical column separation efficiency was explored by achieving binary separations of metal ions like Mg2+-Pb2+, Mg2+- Fe2+, Sr2+-Pb2+, Sr2+-Fe2+, Zn2+-Pb2+, Zn2+- Fe2+. This study could lead to the synthesis of low cost photocatalysts highly efficient for the removal of environmentally hazardous dyes and metal ions from aqueous solution. (C) 2019 Published by Elsevier B.V.