Zn-doped SiO2 nanoparticles preparation and characterization under the effect of various solvents: Antibacterial, antifungal and photocatlytic performance evaluation

The biological profiling (antibacterial and antifungal) and photocatalytic activity (PCA) was evaluated of newly synthesized Zinc-doped SiO2 nanoparticles (Zn-d-SiO2 NPs) under the effect of different solvents (n-hexane, acetonitrile, isoamyl alchol). Antibacterial potential against Bacillus subtilis and Escherichia coli, and antifungal activities against Candida parapsilosis and Aspergilus niger were investigated by the Disc diffusion method. The advanced techniques including Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), Thermo-gravimeteric Analysis (TGA), Atomic forced microscopy (AFM) and Dynamic Light Scattering (DLS) were used for the characterization of Zn-d-SiO2 NPs. FT-IR characterization confirmed the presence of metal bond SiO2, while XRD showed the hexagonal structure with 7.93 nm average particle size of Zn-d-SiO2 NPs. SEM and TEM analysis revealed the variation in morphology of NPs prepared in different solvents. The Zn-d-SiO2 NPs prepared in the presence of acetonitrile showed highest antibacterial activities (6% and 4.5%) followed by isoamyl alchol (3% and 2.4%) and n-hexane (2%and 1%) against B. subtilis and E. coli, respectively. The antifungal activities were recorded in following order; n-hexane (0.34% and 0.43%) < isoamyl alchol (0.27% and 0.19%) < acetonitrle (0.21% and 0.17%) against C. parapsilosis and A. niger, respectively. The PCA of Zn-d-SiO(2 )NPs was evaluated by degrading Crystal Violet (CV) dye under solar light irradiation and up to 85.5% dye degradation was achived for 120 min irradiation. Results revealed that the solvents have a significant effect on physicochemical properties and Zinc-doped SiO2 NPs showed promising PCA and antimicrobial activities.