Influence of ammonia on properties of TiO₂‐MgFe₂O₄ as high visible‐light active photocatalysts for the degradation of Rhodamine B

Abstract

The influence of ammonia on TiO 2 -MgFe 2 O 4 catalysts synthesized via a hydrolysis and co-precipitation, followed by calcination at 500 o C, was studied. Two different catalysts, TiO 2 -MgFe 2 O 4 (Am) and TiO 2 -MgFe 2 O 4 (W), were prepared using Ti-precursors, which were synthesized by the hydrolysis of Ti-butoxide with and without ammonia. The resulting TiO 2 -MgFe 2 O 4 catalysts were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), specific surface area measurements, X-ray diffraction, and UV-vis diffuse reflectance techniques. It was revealed that strong electronic coupling exists between the TiO 2 and MgFe 2 O 4 components within the TiO 2 -MgFe 2 O 4 catalysts. Photocatalytic activity toward Rhodamine B (RhB) was investigated in aqueous solution under visible light irradiation. TiO 2 -MgFe 2 O 4 (W) was found to be an effective catalyst and had several advantages over TiO 2 -MgFe 2 O 4 (Am). These results clearly highlight that ammonia had a significant influence on the photocatalytic activity of the TiO 2 -MgFe 2 O 4 catalysts. Therefore, the results reported herein indicate that TiO 2 -MgFe 2 O 4 is a green, low-cost, and highly efficient photocatalyst for environmental remediation.

Chitosan-Mediated Coupling of MgFe2O4–TiO2 Nanocomposites for Efficient Methylene Blue Photodegradation

“…23 As of late, magnesium ferrite [MgFe 2 O 4 (MFO)] has been an attractive option for magnetic materials and photocatalysis, thanks to its small bandgap (∼2 eV) and low toxicity. 24,25 Since the ferrite structural stability and assisting magnetic properties can be reasonably promoted upon the addition of Mg 2+ , 26,27 the MFO material has become a good candidate for combining with TiO 2 nanoparticles, forming the coupling of magnesium ferrite with titanium dioxide (MFO-TiO 2 ) composite with enhanced photocatalytic characteristics.…”

“…Moreover, the supermagnetic trait of ferrite molecules naturally allows for high recycling capacity after treatment processes, providing a sustainable solution against trace organic pollutants in aquatic media. , Therefore, the doping of spinel ferrite into the TiO 2 matrix can effectively lower the overall bandgap energy of the semiconducting composite, which facilitates the transportation of excited electrons and holes toward active sites of TiO 2 to initiate photo-oxidation . As of late, magnesium ferrite [MgFe 2 O 4 (MFO)] has been an attractive option for magnetic materials and photocatalysis, thanks to its small bandgap (∼2 eV) and low toxicity. , Since the ferrite structural stability and assisting magnetic properties can be reasonably promoted upon the addition of Mg 2+ , , the MFO material has become a good candidate for combining with TiO 2 nanoparticles, forming the coupling of magnesium ferrite with titanium dioxide (MFO-TiO 2 ) composite with enhanced photocatalytic characteristics.…”