Microbial synthesis of titanium dioxide nanoparticles and their importance in wastewater treatment and antimicrobial activities: a review

Nanotechnology (NT) and nanoparticles (NPs) have left a huge impact on every field of science today, but they have shown tremendous importance in the fields of cosmetics and environmental cleanup. NPs with photocatalytic effects have shown positive responses in wastewater treatment, cosmetics, and the biomedical field. The chemically synthesized TiO2 nanoparticles (TiO2 NPs) utilize hazardous chemicals to obtain the desired-shaped TiO2. So, microbial-based synthesis of TiO2 NPs has gained popularity due to its eco-friendly nature, biocompatibility, etc. Being NPs, TiO2 NPs have a high surface area-to-volume ratio in addition to their photocatalytic degradation nature. In the present review, the authors have emphasized the microbial (algae, bacterial, fungi, and virus-mediated) synthesis of TiO2 NPs. Furthermore, authors have exhibited the importance of TiO2 NPs in the food sector, automobile, aerospace, medical, and environmental cleanup.

New development and photocatalytic performance and antimicrobial activity of α-NH4(VO2)(HPO4) nanosheets

α-NH₄(VO₂)(HPO₄) nanosheets were developed by hydrothermal method. Furthermore, it's determined by the several analyses like XRD, Raman, FESEM, TEM, UV-Visible spectroscopy, TGA and DRS UV-Visible spectroscopy studies. The orthorhombic crystalline phase of α-NH₄(VO₂)(HPO₄) nanosheets were recognized by XRD analysis. The α-NH₄(VO₂)(HPO₄) nanosheets functional groups identification was investigated by Raman spectroscopy. Thermal gravimetric analysis of α-NH₄(VO₂)(HPO₄) nanosheets were identified and its attain for three decomposition stages. The nanosheets of the α-NH₄(VO₂)(HPO₄) was clearly evaluated by FESEM and TEM measurements. α-NH₄(VO₂)(HPO₄) nanomaterial band gap energy was determined by DRS UV Visible spectroscopy analysis and the calculated bandgap energy is 1.83 eV. Hence, it was more convenient way for the dye degradation applications. These α-NH₄(VO₂)(HPO₄) nanosheets was will be tested in the photocatalytic and antimicrobial applications. In this case, antimicrobial study was not encouraged in the catalyst. Consequently, this material has more encouraging for electrostatic interaction with enhanced for the applications.

Global popularization of CuNiO2 and their rGO nanocomposite loveabled to the photocatalytic properties of methylene blue

New advancements of photocatalytic activity with higher efficiency, low price are most important, which is challenging in industrialized and many fields. We have introduced CuNiO₂ and CuNiO₂/rGO nanocomposite was generally prepared by the hydrothermal treatment and tested to the photocatalytic studies. Photocatalytic measurements of CuNiO₂ with different weight percentages CuNiO₂/rGO (25/75), (50/50), and (75/25) are achieved to the efficiency under visible light, in this case, CuNiO₂/rGO (50/50) composite have the highest performance is scrutinized. This was obeyed for a synergistic effect between CuNiO₂ nanoparticles and rGO composites. Furthermore, the CuNiO₂, CuNiO₂/rGO (25/75), (50/50), and (75/25) nanocomposite were tested by several analyses like XRD, FT-IR, DRS UV Visible spectroscopy, Raman spectroscopy, and FESEM & HRTEM investigations. In this regard all measurements are very clear and satisfied; therefore we are encouraged for future developing environmental applications.

Enhanced Photocatalytic Performance of Sn6SiO8 Nanoparticles and Their Reduced Graphene Oxide (rGO) Nanocomposite

Photocatalysts provide excellent potential for the full removal of organic chemical pollutants as an environmentally friendly technology. It has been noted that under UV-visible light irradiation, nanostructured semiconductor metal oxides photocatalysts can degrade different organic pollutants. The Sn₆SiO₈/rGO nanocomposite was synthesized by a hydrothermal method. The Sn₆SiO₈ nanoparticles hexagonal phase was confirmed by XRD and functional groups were analyzed by FT-IR spectroscopy. The bandgap of Sn₆SiO₈ nanoparticles (NPs) and Sn₆SiO₈/GO composites were found to be 2.7 eV and 2.5 eV, respectively. SEM images of samples showed that the flakes like morphology. This Sn₆SiO₈/rGO nanocomposite was testing for photocatalytic dye degradation of MG under visible light illumination and excellent response for the catalysts. The enhancement of photocatalytic performance was mainly attributed to the increased light absorption, charge separation efficiency and specific surface area, proved by UV-vis DRS. Further, the radical trapping experiments revealed that holes (h⁺) and superoxide radicals (·O^-₂) were the main active species for the degradation of MG, and a possible photocatalytic mechanism was discussed.

Visible-Light Driven Effective Photocatalytic Degradation of Methylene Blue Dye Using Perforated Curly Zn0.1Ni0.9O Nanosheets

Herein, we report the facile synthesis, characterization and visible-light-driven photocatalytic degradation of perforated curly Zn_0.1Ni_0.9O nanosheets synthesized by hydrothermal process. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies confirmed the cubic phase crystalline structure and growth of high density perforated curly Zn_0.1Ni_0.9O nanosheets, respectively. As a photocatalyst, using methylene blue (MB) as model pollutant, the synthesized nanosheets demonstrated a high degradation efficiency of ~76% in 60 min under visible light irradiation. The observed results suggest that the synthesized Zn_0.1Ni_0.9O nanosheets are attractive photocatalysts for the degradation of toxic organic waste in the water under visible light.

Facile solvothermal decomposition synthesis of single phase ZnBi38O60 nanobundles for sensitive detection of 4-nitrophenol

We have developed the facile solvothermal decomposition route to fabricate a single phase zinc bismuthate (ZnBi₃₈O₆₀) binary composite nanostructure.