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We investigated how different doses of microwave irradiation (MR) affect seed germination in Sorghum, including the level of remediation against textile and surgical wastewater (WW) by modulating biochemical and morpho-physiological mechanisms under glutamic acid (GA) application. The experiment was conducted to determine the impact of foliar-applied GA on Sorghum under wastewater conditions. Plants were treated with or without microwave irradiation (30 s, 2.45 GHz), GA (5 and 10 mM), and wastewater (0, 25, 50, and 100). Growth and photosynthetic pigments were significantly decreased in plants only treated with various concentrations of WW. GA significantly improved the plant growth characteristics both in MR-treated and -untreated plants compared with respective controls. HMs stress increased electrolyte leakage (EL), hydrogen peroxide (H2O2), and malondialdehyde (MDA) content; however, the GA chelation significantly improved the antioxidant enzymes activities such as ascorbate oxidase (APX), superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) both in MR-treated and -untreated plants under WW stress compared with respective controls. The results suggested that the MR-treated plants accumulate higher levels of HMs under GA addition in comparison to the WW-only-treated and MR-untreated plants. The maximum increase in Cd accumulation was observed in the range of 14–629% in the roots, 15–2964% in the stems, and 26–4020% in the leaves; the accumulation of Cu was 18–2757% in the roots, 15–4506% in the stems, and 23–4605% in the leaves; and the accumulation of Pb was 13–4122% in the roots, 21–3588% in the stems, and 21–4990% in the leaves under 10 mM GA and MR-treated plants. These findings confirmed that MR-treated sorghum plants had a higher capacity for HMs uptake under GA and could be used as a potential candidate for wastewater treatment. [ABSTRACT FROM AUTHOR]

Among chemical water pollutants, Cr(VI) is a highly toxic heavy metal; solar photocatalysis is a cost-effective method to reduce Cr(VI) to innocuous Cr(III). In this research work, an efficient and economically feasible ZnO/CuO nanocomposite was grafted onto the polyester fabric ZnO/CuO/PF through the SILAR method. Characterization by SEM, EDX, XRD, and DRS confirmed the successful grafting of highly crystalline, solar active nanoflakes of ZnO/CuO nanocomposite onto the polyester fabric. The grafting of the ZnO/CuO nanocomposite was confirmed by FTIR analysis of the ZnO/CuO/PF membrane. A solar photocatalytic reduction reaction of Cr(VI) was carried out by ZnO/CuO/PF under natural sunlight (solar flux 5–6 kW h/m2). The response surface methodology was employed to determine the interactive effect of three reaction variables: initial concentration of Cr(VI), pH, and solar irradiation time. According to UV/Vis spectrophotometry, 97% of chromium was removed from wastewater in acidic conditions after four hours of sunlight irradiation. ZnO/CuO/PF demonstrated reusability for 11 batches of wastewater under natural sunlight. Evaluation of Cr(VI) reduction was also executed by complexation of Cr(VI) and Cr(III) with 1, 5-diphenylcarbazide. The total percentage removal of Cr after solar photocatalysis was carried out by AAS of the wastewater sample. The ZnO/CuO/PF enhanced the reduction of Cr(VI) metal from wastewater remarkably. [ABSTRACT FROM AUTHOR]

Water purification is a critical problem for the development and survival of human society, and now it has become a great challenge for the research community. Therefore, MOFs attracted the great intention owing to the large number of active sites, and tailorable porous composition as a fast-growing branch of coordination chemistry. Moreover, MOF-based photocatalysts have proven to be excellent adsorbents in photocatalysis for wastewater treatment. In current review, we have discussed the various synthesis routes, and historical developments of the MOFs. Additionally, recent developments have been explored in the removal, and degrading hexavalent chromium through MOFs under visible light irradiations. In addition, this review demonstrated the development of sustained and efficient metal-organic materials (MOMs), and their modularity, fine-tuneable, and diverse composition with structural features. In this context, numerous investigations have been explored with their classifications of MOF-based heterostructures including 0D, 1D, 2D, and 3D materials, according to their structural, morphological and nature of the catalyst. Furthermore, we have explored the different parameters to enhance photocatalytic reducing ability of hexavalent chromium (Cr6+). In summary, various challenges and future prospects are explained for further advancements in Cr(VI) reduction through MOFs-based nanocomposites under visible light in aqueous media. [Display omitted] • Recent developments in Cr(VI) reduction over the MOF-based materials are reviewed. • Synthesis routes for MOFs and Cr(VI) reduction mechanism are discussed. • The challenges and opportunities of MOFs for Cr(VI) reduction are provided. [ABSTRACT FROM AUTHOR]

Conversion and reducing agent (NaBH 4) effect on zero valent iron into Fe 3 O 4 nanoparticles with diverse molar ratios of reducing agent was produced through chemical reduction technique. The structural, optical, vibrational analyses were executed via XRD, UV–Vis, Raman, and FT-IR analysis. The crystallite size obtained were 35 nm, 27 nm, and 18 nm for Fe:NaBH 4 (1:1), Fe:NaBH 4 (1:2) and Fe:NaBH 4 (1:3). The morphology of the Fe:NaBH 4 (1:1) was not in good orientation with higher dimensions. As explored in Fe:NaBH 4 (1:2) and (1:3) samples, there is a proper growth of nanoneedles and nanosheets formation. This was due to the addition of reducing agent which greatly helped in enhancement of morphology. The prepared photocatalysts were tested to reduce Malachite Green (MG) under UV illumination. The pure dye solution obtained 57% efficiency after irradiation. Fe:NaBH 4 (1:3) photocatalyst achieved 97% efficiency on reducing pollutants. The rate constant values calculated was 0.007, 0.013, 0.02 and 0.03 min−1 for pure, Fe: NaBH 4 (1:1), Fe: NaBH 4 (1:2) and Fe: NaBH 4 (1:3) assisted MG samples. The as prepared photocatalyst is more potential one on removal of toxic pollutants from wastewater which is due to the better enhancement of nanoneedles and nanosheets oriented by the effect of reducing agent. The advantage of Fe 3 O 4 nanoparticles for wastewater is that the removal of these nanoparticles can be ease with magnetic separation methods. On considering the advantage of removing of photocatalyst and efficiency, this prepared product is suitable one for wastewater remediation process in future days. • The pure dye solution obtained 57% efficiency after irradiation. • Fe:NaBH 4 (1:3) photocatalyst achieved 97% efficiency on reducing pollutants. • The rate constant values calculated was 0.007, 0.013, 0.02 and 0.03 min−1. [ABSTRACT FROM AUTHOR]

Treatment of wastewater for reuse is an important strategy undertaken to deal with water scarcity. In this study, pure and La-doped barium ferrites were produced using a facile hydrothermal technique. Lanthanum was doped at 1% and 2% molar ratio and the obtained product was analyzed for further confirmation of crystal structure, optical properties, vibrational properties, and morphology. X-ray powder diffraction pattern confirmed material formation. Bandgap energies were estimated from a Tauc plot. The vibrational properties of the pure and doped samples were examined by Fourier-transform infrared spectra. The pure barium ferrite sample showed a spherical agglomerated morphology. The 1% La-doped barium ferrite sample showed reduced agglomeration and the particles were attached together. The 2% La-doped barium ferrite sample showed small nanoballs with no agglomeration on the surface. The transmission electron microscopy images confirmed no agglomeration for the 2% La-BaFe 2 O 4 sample. The M–H loop revealed the ferromagnetic behavior of the pristine and doped samples. The 2% La-BaFe 2 O 4 sample had 24.53 m2/g surface area. The photocatalytic activity was examined employing degrading methylene blue under ultraviolet (UV) and visible light. Prepared product showed better efficiency on UV light exposure. The 2% La-doped barium ferrite sample exhibited almost 80% of efficiency under UV light and 85% efficiency under visible light toward toxic pollutants. The sample attained 0.02 min−1 rate constant value. The main advantage of ferrite samples is that the particles can be separated by magnetic methods and the water will be fit for reuse. The sample will be a promising candidate for use in the wastewater treatment. [Display omitted] • 2% La-BaFe 2 O 4 product exhibited good nanostructures. • 2% La-BaFe 2 O 4 showed enhanced efficiency on reducing toxic pollutant. • 2% La-BaFe 2 O 4 exhibited 85% efficiency towards toxic pollutant. • 2% La-BaFe 2 O 4 sample will be the potential candidate for wastewater treatment. [ABSTRACT FROM AUTHOR]