Reduced Ag NPs-modified NaTaO3 layer improves photocatalytic degradation and antimicrobial ability through LSPR effect and doping behavior

Abstract

Reduced Ag NPs modified Ag-doped NaTaO 3 layer photocatalysts were prepared using the hydrothermal method . The research investigated the microstructure and degradation ability of composite layer containing Ag-NaTaO 3 . Various techniques, including SEM,TEM, XRD, UV–Vis and PL analyses, were used for the evaluation. The antibacterial effect of the Ag-NaTaO 3 layers on Staphylococcus aureus (S. aureus) before and after modification with reduced Ag NPs was evaluated. The Ag-NaTaO 3 composite layer showed stronger degradation effect and bactericidal activity than NaTaO 3 under the optimal conditions (Concentration of Ag + -containing solution 0.1 mol/L, reaction temperature 200 ℃, reaction time 3 h). The degradation efficiency of Ag3-NaTaO 3 for MB was 87.6 % after 50 min, and the bactericidal inhibition rate was 100 % after 20 min. The degradation process, with electron hole ( h + ) as the main active substance, conforms to the first-order kinetic with a rate constant ( K ) value of 0.0310 min −1 . The band gaps (Eg) of the calculated pure phase NaTaO 3 and Ag3-NaTaO 3 are 3.18 eV and 2.75 eV, correspondingly. The fluorescence decay spectra indicate that the average expected lifetimes of Ag3-NaTaO 3 composites rounded is 11.45 ns, respectively. The NaTaO 3 nano-cubic structure, prepared using Ta 2 O 5 precursor, reduces the grain size, provides more surface active sites, and effectively improves the range of the NaTaO 3 photoresponse. AgNO 3 solution is used to reduce Ag NPs and carry out doping behavior. The LSPR behavior of Ag NPs and the doping behavior of Ag lower the Schottky barrier that is made up of the metal–semiconductor interface. This ensures that the hot metal electrons are injected into the semiconductors efficiently, improves the electron-hole (h + ) separation efficiency, and enhances the photocatalytic activity. The bacterial structure was destroyed through a dual mechanism of reactive oxygen species (ROS) (·OH, ·O 2 – ) and Ag properties, achieving excellent bacterial inhibition. This study proposes a new concept to enhance the photocatalytic performance of NaTaO 3 thinfilm materials, which will could have significant applications in the field of wastewater treatment.

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