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An in‐depth investigation was conducted on a promising composite material (BiVO4/TiO2), focusing on its potential toxicity, photoinduced catalytic properties, as well as its antibiofilm and antimicrobial functionalities. The preparation process involved the synthesis of 2D TiO2 using the lyophilization method, which was subsequently functionalized with sphere‐like BiVO4 through wet impregnation. Finally, we developed BiVO4/TiO2 S‐scheme heterojunctions which can greatly promote the separation of electron‐hole pairs to achieve high photocatalytic performance. The evaluation of concentration‐ and time‐dependent viability inhibition was performed on human lung carcinoma epithelial A549 cells. This assessment included the estimation of glutathione levels and mitochondrial dehydrogenase activity. Significantly, the BiVO4/TiO2 composite demonstrated minimal toxicity towards A549 cells. Impressively, the BiVO4/TiO2 composite exhibited notable photocatalytic performance in the degradation of rhodamine B (k=0.135 min−1) and phenol (k=0.016 min−1). In terms of photoinduced antimicrobial performance, the composite effectively inactivated both gram‐negative E. coli and gram‐positive E. faecalis bacteria upon 60 minutes of UV‐A light exposure, resulting in a significant log 6 (log 10 CFU/mL) reduction in bacterial count. In addition, a 49 % reduction of E. faecalis biofilm was observed. These promising results can be attributed to the unique 2D morphology of TiO2 modified by sphere‐like BiVO4, leading to an increased generation of (intracellular) hydroxyl radicals, which plays a crucial role in the treatments of both organic pollutants and bacteria. This research has significant potential for various applications, particularly in addressing environmental contamination and microbial infections. [ABSTRACT FROM AUTHOR]

Manganese is naturally present in water, but its increased concentration in potable water is undesirable for multiple reasons. This study investigates an alternative method of demanganization by a newly synthesized TiO2-based adsorbent prepared through the transformation of titanyl sulphate monohydrate to amorphous sodium titanate. Its adsorption capacity for Mn2+ was determined, while a range of influential factors, such as the effect of contact time, adsorbent dosage, pH value, and added ions was evaluated. The adsorbent appeared highly effective for Mn2+ removal owing to its unique characteristics. Besides adsorption via electrostatic interactions, ion-exchange was also involved in the Mn2+ removal. Although the Mn2+ removal occurred within the whole investigated pH range of 4–8, the maximum was achieved at pH 7, with qe = 73.83 mg g-1. Equilibrium data revealed a good correlation with Langmuir isotherm in the absence of any ions or in the presence of monovalent co-existing ions, while the results in the presence of divalent co-existing ions showed a better fit to Freundlich isotherm. Additionally, the presence of monovalent cations (Na+, K+) only slightly decreased the Mn2+ removal efficiency as compared to divalent cations (Ca2+, Mg2+) that caused a greater decrease; however, the effect of anions (Cl-, SO42-) was insignificant. To provide insight into the adsorbent safety, the toxicity assessment was performed and showed no harmful effect on cell activity. Furthermore, the residual concentration of titanium after adsorption was always below the detection limit. The results imply that the synthesized TiO2-based adsorbent is a safe promising alternative method for demanganization. Highlights The synthesis of amorphous TiO2-based adsorbent was presented. The TiO2-based adsorbent was found to be efficient for Mn2+ removal. The Mn2+ removal mechanisms were adsorption and ion-exchange. Increasing pH enhanced the efficiency of Mn2+ removal. Divalent cations decreased the Mn2+ removal efficiency more than monovalent cations. [ABSTRACT FROM AUTHOR]

An in-depth investigation was conducted on a promising composite material (BiVO 4 /TiO 2 ), focusing on its potential toxicity, photoinduced catalytic properties, as well as its antibiofilm and antimicrobial functionalities. The preparation process involved the synthesis of 2D TiO 2 using the lyophilization method, which was subsequently functionalized with sphere-like BiVO 4 through wet impregnation. Finally, we developed BiVO 4 /TiO 2 S-scheme heterojunctions which can greatly promote the separation of electron-hole pairs to achieve high photocatalytic performance. The evaluation of concentration- and time-dependent viability inhibition was performed on human lung carcinoma epithelial A549 cells. This assessment included the estimation of glutathione levels and mitochondrial dehydrogenase activity. Significantly, the BiVO 4 /TiO 2 composite demonstrated minimal toxicity towards A549 cells. Impressively, the BiVO 4 /TiO 2 composite exhibited notable photocatalytic performance in the degradation of rhodamine B (k=0.135 min -1 ) and phenol (k=0.016 min -1 ). In terms of photoinduced antimicrobial performance, the composite effectively inactivated both gram-negative E. coli and gram-positive E. faecalis bacteria upon 60 minutes of UV-A light exposure, resulting in a significant log 6 (log 10 CFU/mL) reduction in bacterial count. In addition, a 49 % reduction of E. faecalis biofilm was observed. These promising results can be attributed to the unique 2D morphology of TiO 2 modified by sphere-like BiVO 4 , leading to an increased generation of (intracellular) hydroxyl radicals, which plays a crucial role in the treatments of both organic pollutants and bacteria. This research has significant potential for various applications, particularly in addressing environmental contamination and microbial infections., (© 2024 Wiley-VCH GmbH.)

Manganese is naturally present in water, but its increased concentration in potable water is undesirable for multiple reasons. This study investigates an alternative method of demanganization by a newly synthesized TiO 2 -based adsorbent prepared through the transformation of titanyl sulphate monohydrate to amorphous sodium titanate. Its adsorption capacity for Mn 2+ was determined, while a range of influential factors, such as the effect of contact time, adsorbent dosage, pH value, and added ions was evaluated. The adsorbent appeared highly effective for Mn 2+ removal owing to its unique characteristics. Besides adsorption via electrostatic interactions, ion-exchange was also involved in the Mn 2+ removal. Although the Mn 2+ removal occurred within the whole investigated pH range of 4-8, the maximum was achieved at pH 7, with q e  = 73.83 mg g -1 . Equilibrium data revealed a good correlation with Langmuir isotherm in the absence of any ions or in the presence of monovalent co-existing ions, while the results in the presence of divalent co-existing ions showed a better fit to Freundlich isotherm. Additionally, the presence of monovalent cations (Na + , K + ) only slightly decreased the Mn 2+ removal efficiency as compared to divalent cations (Ca 2+ , Mg 2+ ) that caused a greater decrease; however, the effect of anions (Cl - , SO 4 2- ) was insignificant. To provide insight into the adsorbent safety, the toxicity assessment was performed and showed no harmful effect on cell activity. Furthermore, the residual concentration of titanium after adsorption was always below the detection limit. The results imply that the synthesized TiO 2 -based adsorbent is a safe promising alternative method for demanganization. Highlights The synthesis of amorphous TiO 2 -based adsorbent was presented.The TiO 2 -based adsorbent was found to be efficient for Mn 2+ removal.The Mn 2+ removal mechanisms were adsorption and ion-exchange.Increasing pH enhanced the efficiency of Mn 2+ removal.Divalent cations decreased the Mn 2+ removal efficiency more than monovalent cations.