Evaluation of Bactericidal Potential and Catalytic Dye Degradation of Yttrium/Graphitic Carbon Nitride Doped Nickel Oxide Nanostructures

In this research work, nickel dioxide (NiO₂) with a fixed quantity of graphitic carbon nitride (g-C₃N₄) and various concentrations of yttrium (Y) (2, 4 wt%) were synthesized via the coprecipitation method. The main objective is to degrade hazardous dyes such as Rhodamine B (RhB) with synthetic material and to assess antibacterial and catalytic activity with molecular docking analysis of the synthesized Y/g-C₃N₄-doped NiO₂ nanostructures (NSs). A series of characterizations for optical, morphological, structural, and compositional analysis of prepared NSs were monitored to better understand the obtained samples. X-ray diffraction pattern evaluated the hexagonal structure of NiO₂. Fourier transform infrared spectra demonstrated the prescence of bending and stretching vibration modes. Upon the incorporation of Y and g-C₃N_4, no visible transmittance shift was observed. The high resolution transmission electron microscopy micrographs affirmed the formation of agglomerated NiO₂ NSs with few rod-like shapes, also assured by EDS elemental configuration. The UV–vis spectra revealed a redshift upon including Y and g-C₃N₄ into NiO₂, leading the band gap energy to decrease from 3.6 to 3.4 eV. The catalytic efficacy of prepared samples was examined against Rhodamine B (RhB) dye in the prescence of reducing agent. In an acidic medium, the highest catalytic degradation rate of 99.85% was achieved by 4% Y/g-C₃N₄–NiO_2, ascribed to increased production of H⁺ ions absorbed over the NSs surface. Moreover, the antimicrobial efficacy of synthesized NSs was evaluated against Escherichia coli (E.coli) bacteria and was observed as 3.15 mm. In silico docking studies of g-C₃N₄/NiO₂ and Y/g-C₃N₄–NiO₂ NSs for dihydrofolatereductase (DHFR) and dihydropteroate synthase (DHPS) of E.coli postulated inhibition of the enzymes above as a possible mechanism in addition to their microbicidal activity.