Editorial Expression of Concern: Impact of adding vanadium pentoxide to Mn-doped magnetite for technological uses

Nanocomposites containing different contributions of vanadium oxide (V 2 O 5 ) and magnetite (Fe 3 O 4 ) modified with manganese (Mn) ions were fabricated upon the formula of xMn 0.4 Fe 2.6 O 4 /(1-x)V 2 O 5, whereas x = 0.0, 0.2, 0.4, 0.5, 0.6, 0.8, and 1.0. The obtained compositions were characterized upon their structure, morphology, besides their magnetic susceptibility. The TEM micrographs depicted that V 2 O 5 was formed as rod shapes with diameters of 20–30 nm and length of 450 nm, while Mn–magnetite was configured in ellipsoidal shapes with dimensions 25–40 nm. Moreover, the Maximum height of the roughness(R t ) changed from 507.0 to 220.6 nm, while the skewness (R sk ) increased from 0.104 to 0.122 for ( x = 0.2, and x = 1.0), respectively. Furthermore, Curie Weiss constant (θ) increased from 830 to 890 K and then decreased to 520 K, for x = 0.2, 0.5, and x = 1.0, respectively. The photo-activated antibacterial activity was examined and showed that the inhibition zone increased significantly by increasing the V 2 O 5 content as well as it increased also from dark to light conditions. It was changed from 17.4 ± 1.1 and 16.9 ± 1.3 mm to 19.2 ± 1.4 and 18.9 ± 1.5 mm for pure V 2 O 5 ( x =0.0) against E. coli and S. aureus , respectively. The degradation of methylene blue (MB) was tested, and the efficiency of removal reached around 97.1% for the highest contribution of V 2 O 5 after 35 min of visible light exposure. Hence, the fabricated nanocomposites can be suggested for a deep investigation to be highlighted for disinfection and water treatment applications.