Zn-doped SiO 2 nanoparticles preparation and characterization under the effect of various solvents: Antibacterial, antifungal and photocatlytic performance evaluation

Abstract The biological profiling (antibacterial and antifungal) and photocatalytic activity (PCA) was evaluated of newly synthesized Zinc-doped SiO 2 nanoparticles (Zn-d-SiO 2 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-SiO 2 NPs. FT-IR characterization confirmed the presence of metal bond SiO 2 , while XRD showed the hexagonal structure with 7.93 nm average particle size of Zn-d-SiO 2 NPs. SEM and TEM analysis revealed the variation in morphology of NPs prepared in different solvents. The Zn-d-SiO 2 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%)  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 SiO 2 NPs showed promising PCA and antimicrobial activities.