Biofabrication, spectroscopic, and photocatalytic studies of titania nanoparticles mediated by Proteus mirabilis strain NG-ABK-32 for smart applications

ABSTRACT

Green fabrication of nanoparticles (NPs) is simple, pocket-friendly, easy, sustainable, and devoid of eco-toxicity issues. Thirty-five bacterial strains were isolated from ‘tie and dye’ effluent-contaminated soil and effluent samples and were identified using traditional methods. Following a dye decolourization assay, Proteus mirabilis strain (NG-ABK-32) emerged as the isolate with the highest potential to decolourize vat violet RR dye. Titania nanoparticles (TiO₂ NPs) fabricated using NG-ABK-32 strain were characterized by UV-visible spectroscopy (UV-vis), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), and Fourier Transform Infrared (FT-IR) spectroscopy. UV-Vis result displayed an absorption peak at 320 nm. The TEM image revealed monodispersed, spherical NPs possessing an average particle size of 3.18 nm. The crystallographic plane of rutile TiO₂ NPs and high purity were confirmed by the XRD pattern. The average crystallite size was 52.53 nm. The synthesis of TiO₂ NPs was further established from FT-IR by the presence of Ti-O, Ti-OH, and O-Ti-O functional groups. The synergistic treatment caused a significant reduction of total suspended solids (TSS), total dissolved solids (TDS), biological oxygen demand (BOD), chemical oxygen demand (COD), and color (Pt.Co) of the effluent by 96.86%, 78.78%, 67.84%, 56.65%, 67.84%, and 72.09% respectively. Thus, this study confirmed the better efficiency of combining biological (NG-ABK-32) pre-treatment with photocatalytic degradation post-treatment using the synthesized TiO₂ NPs in the treatment of ‘tie and dye’ effluent compared to the application of the TiO₂ NPs as a single treatment method.

GRAPHICAL ABSTRACT

KEYWORDS:

• Nanotechnology
• biofabrication
• TiO₂ NPs
• Proteus mirabilis strain NG-ABK-32
• synergistic treatment
• photocatalytic degradation

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

No grants were awarded to this research by public, private, or non-profit funding organizations