Visible light photocatalysts from low-grade iron ore: the environmentally benign production of magnetite/carbon (Fe3O4/C) nanocomposites.

Magnetite (Fe3O4) nanoparticles coated with dextrose and gluconic acid possessing both super-paramagnetism and excellent optical properties have been productively synthesized through a straightforward, efficient and cost-efficient hydrothermal reduction route using Fe3+ as sole metal precursor acquired from accumulated iron ore tailings-a mining waste that usually represents a major environmental threat. Fe3O4/C nanocomposites were fully elucidated by FEGSEM and TEM, revealing a combination of platelets (<1 µm) capped by particles (<10 nm) and magnetite which was verified by XPS, which demonstrated also oxygen deficiency. A dextrose/gluconic acid coating was elucidated by Fourier transform-infrared (FT-IR) spectroscopy and thermogravimetric analysis (TGA). The Fe3O4/C nanocomposites were found to be superparamagnetic at room temperature. Meanwhile, their optical properties were investigated by UV-visible diffuse reflectance spectroscopy (UV-vis DRS) and photoluminescence (PL) spectroscopy; an Eg of 1.86 eV was determined, and emissions at 612 and 650 nm (ex. 250 nm) were consistent with the XPS identification of oxygen vacancies. The efficacy of the as-synthesized magnetically recoverable magnetite/carbon (Fe3O4/C) nanocomposites has been exhibited in the photocatalytic degradation of the toxic textile (industrial) dye bodactive red BNC-BS.

A ratiometric triazine-based colorimetric and fluorometric sensor for the recognition of Zn2+ ions and its application in human lung cancer cells.

Herein, we introduce new ratiometric 2,4,6-triamino-1,3,5-triazine-based probes (R1 and R2) having three different binding sites for three metal ion binders, which can selectively detect Zn2+ ions and, particularly, the probe R1 strongly interacts with the human lung cancer cell line (A549). Both the probes R1 and R2 are competently selective towards the Zn2+ ions with the detection limits of 1.22 × 10-7 M and 1.13 × 10-7 M, respectively. The changes in the structure and absorption properties of the probes are explained by density functional theory (DFT) and time dependent density functional theory (TDDFT) calculations. The absorption and fluorescence color change in the solid TLC plate makes it a brilliant Zn2+ sensor in a portable form.