Enhanced performance of lanthanum orthoferrite/chitosan nanocomposites for adsorptive photocatalytic removal of Reactive Black 5

Harnessing the photocatalytic potential of bismuth ferrite-activated carbon nanocomposite (BFO-AC) for Staphylococcus aureus decontamination under visible light

In response to the escalating global issue of microbial contamination, this study introduces a breakthrough photocatalyst: bismuth ferrite-activated carbon (BFO-AC) for visible light-driven disinfection, specifically targeting the Gram-positive bacterium Staphylococcus aureus (S. aureus). Employing an ultrasonication method, we synthesized various BFO-AC ratios and subjected them to comprehensive characterization. Remarkably, the bismuth ferrite-activated carbon 1:1.5 ratio (BA 1:1.5) nanocomposite exhibited the narrowest band gap of 1.86 eV. Notably, BA (1:1.5) demonstrated an exceptional BET surface area of 862.99 m2/g, a remarkable improvement compared to pristine BFO with only 27.61 m2/g. Further investigation through FE-SEM unveiled the presence of BFO nanoparticles on the activated carbon surface. Crucially, the photocatalytic efficacy of BA (1:1.5) towards S. aureus reached its zenith, achieving complete inactivation in just 60 min. TEM analysis revealed severe damage and rupture of bacterial cells, affirming the potent disinfection capabilities of BA (1:1.5). This exceptional disinfection efficiency underscores the promising potential of BA (1:1.5) for the treatment of contaminated water sources. Importantly, our results underscore the enhanced photocatalytic performance with an increased content of activated carbon, suggesting a promising avenue for more effective microorganism inactivation.

Efficient liquid phase confiscation of nile blue using a novel hybrid nanocomposite synthesized from guar gum-polyacrylamide and erbium oxide

In recent times, biopolymer-metal oxide nanocomposites have gained prominent importance in the attenuation of environmental toxicants from aqueous phase. But lanthanide oxide-based biopolymer nanocomposites have scantly been evaluated for their adsorption potential. A novel guar gum-polyacrylamide/erbium oxide nanocomposite (GG-PAAm/Er₂O₃ NC) adsorbent was synthesized by copolymerization of guar gum (GG) and acrylamide (AAm) utilizing N-N′-methylenebisacrylamide as a crosslinker and Er₂O₃ as a reinforcing agent. The adsorptive efficacy of GG-PAAm/Er₂O₃ nanocomposite was evaluated using nile blue (NB) as a model pollutant dye from aquatic system. The prepared adsorbent was characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) analysis, Brunauer–Emmett–Teller (BET) analysis, thermogravimetric analysis, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM–EDX), and high-resolution transmission electron microscopy (HRTEM). The optimal process parameters, which include dosage (0.8 g/L), agitation time (40 min), initial solution pH (6), and initial NB concentration (80 mg/L) were determined by batch methodology. The equilibrium data for NB confiscation was better expressed by Langmuir isotherm model, with maximal adsorption effectiveness (Q_m) of 225.88 mg NB/g demonstrating the actively monolayer adsorption onto homogeneous surface of GG-PAAm/Er₂O₃ NC. The kinetics of NB sorption process onto GG-PAAm/Er₂O₃ NC was reliable with pseudo-second order model. Thermodynamic parameters such as ΔH^° (15–17 kJ/mol) and ΔS^° (0.079–0.087 kJ/mol/K), and − ΔG^° (8.81–10.55 kJ/mol) for NB validated the endothermic, an increased randomness at the GG-PAAm/Er₂O₃–NB interface, and spontaneity and feasibility of the process, respectively. The spent nanocomposite was effectively regenerated with NaOH, and could be reused proficiently for five runs demonstrating the high reusability potential of the nanocomposite. The commendable removal efficiency and high reusability of GG-PAAm/Er₂O₃ NC recommended it to be a highly competent adsorbent for cationic dyes particularly NB diminution from aqueous waste.