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TiO2 modified gold nanocomposites (Au-TiO2 NCs) were synthesized as a platform for the investigation and degradation of organic pollutants in the real environmental sample, lake soil. The prepared Au-TiO2 NCs show the surface plasmon resonance band at 532 nm. The crystallinity and the formation of Au-TiO2 NCs were confirmed by using X-ray diffraction and vibrational studies. Transmission electron microscope measurement shows the core shell structure of Au-TiO2 NCs. It reveals good photocatalytic activity for degrading pollutants in the lake soil. Using surface enhanced raman scattering the pollutants were detected and it is further confirmed through gas chromatography and mass spectrometry analysis. Au-TiO2 NCs degrades the organic pollutants in lake soil and the apparent rate constant of the catalytic reaction is 0.022/min. The observed experimental results show that the high stability Au-TiO2 NCs act as good candidate, both for the detection and degradation of pollutants. [ABSTRACT FROM AUTHOR]

The photocatalytic and antibacterial properties of graphene biosynthesized from sugar and anchored on sand particles has been focused here. The morphology and composition of the synthesized Graphene Sand Composite (GSC) was investigated by means of X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDAX), Fourier Transform Infra-red Spectroscopy (FTIR) and UV–Visible spectroscopy. SEM images show wrinkly edges. This is characteristic of graphenic morphology. Three types of waste water samples namely, textile waste (TW), sugarcane industrial waste water (SW) and domestic waste water from a local purification center at Kodaikanal (KWW) were collected and treated. Adsorption experiments showed effective removal of impurities at 0.2 g of GSC. Photocatalytic activity was analyzed under visible and ultraviolet irradiation. The rate constant for TW increased to 0.0032/min for visible light irradiation from 0.0029/min under UV irradiation. SW showed similar improved activity with rate constant as 0.0023/min in visible irradiation compared to 0.0016/min under UV irradiation. For KWW enhanced activity was seen only in visible light irradiation with rate constant 0.0025/min. GSC showed an inhibition zone of 20 mm against the bacterium Escherichia coli . Results suggest development of economic and effective waste water management systems. [ABSTRACT FROM AUTHOR]

Carbon nano cone and disc-fluorine-co-doped-titanium dioxide nanocomposites were synthesized by the solid state method. The physical and chemical properties of the prepared nanocomposites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and field emission-scanning electron microscopic (FE-SEM) techniques. In addition, a detailed study of antimicrobial activity and photocatalytic activity of the prepared nanoparticles were tested for its efficiency. Carbon cone and disc-doping into TiO 2 showed not only the improvement in UV light absorption, but also in the creation of surface oxygen vacancies. Fluorine-doping produced several beneficial effects, including the formation of surface oxygen vacancies and the enhancement of Ti 3+ ions. XRD analysis showed the formation of TiO 2 anatase phase in all cases. FE-SEM image, Fig. 3 d revealed irregular shapes of carbon cone and disc. The photocatalytic tests indicated that the carbon cone and disc-fluorine-co-doped TiO 2 nanocubes have high UV light activity in degradation of methyl orange, which could be attributed to the creation of oxygen vacancies, increase the concentration of • OH radicals in the solution, which is beneficial for improving the photodegradation rate of organic compounds. The carbon cone and disc-fluorine-TiO 2 nanocomposites act as a strong antibacterial agent. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fluorine doped TiO2 was synthesized by solid state reaction method. [•] Tetragonal in crystalline structure. [•] Shows smaller band gap. [•] Shows higher photocatalytic activity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fluorine doped TiO2 was synthesized by chemical reaction method. [•] Hexagonal in crystalline structure. [•] Shows strong antibacterial agent. [•] Shows higher photocatalytic activity. [•] Shows high photovoltaic properties. [ABSTRACT FROM AUTHOR]

Highlights: [•] NiO nanoparticles were synthesized by solution combustion method. [•] Prepared NiO nanoparticles are fcc structure. [•] Synthesized NiO nanoparticles are octahedral shape. [•] Shows good photocatalytic activity. [Copyright &y& Elsevier]

Abstract: Copper oxide (CuO) nanoflowers were prepared by solution combustion method and glycine was used as fuel. The prepared nanoflowers are monoclinic in crystalline structure. FESEM and HRTEM studies confirmed the flower like structure of the CuO. The CuO nanoflowers were composed of wide nanopetals/sheets. CuO nanoflowers show very good photocatalytic activity. The apparent rate constant of this catalytic reaction was 0.016/min. The estimated direct band gap energy of the CuO was 3eV. [Copyright &y& Elsevier]

Abstract: Copper oxide (CuO) nanoparticles have been prepared by solution combustion method using citric acid as fuel. The structure and morphology of the CuO nanoparticles were investigated by means of X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and energy dispersion spectra (EDS) techniques. The rod like nature and monoclinic crystalline structure of the prepared CuO nanoparticles were revealed from FESEM, HRTEM and XRD. The CuO NPs showed very good antimicrobial activity against Bacillus cereus, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. Photocatalytic activities of CuO nanorods were also investigated. [Copyright &y& Elsevier]

Graphical abstract Highlights • Solvothermally synthesized TAG NC dual SERS and degradation substrates were studied. • Characteristic azo and aryl SERS bands were observed for CR and CV respectively. • Visible light driven degradation of CR and CV were analyzed in the presence of TAG. • Degradation rate constants of 1.09 × 10−2 & 1.26 × 10−2/min for CR & CV was observed. • Synergistically, plasmonic Ag, anatase TiO 2 and GO aid the detection & degradation. Abstract Environmental process such as toxic dye sensing and degradation can be stepped up through photochemical process such as surface enhanced Raman scattering (SERS) and llight induced catalytic degradation. In this work, Titanium dioxide/silver/graphene oxide nanocomposites (TAG) were studied as ideal dual substrates for SERS sensing and visible light driven degradation of Congo red (CR) and crystal violet (CV). Solvothermal route of synthesize used here resulted in a narrow size distribution (6–12 nm) of TAG. A shift towards the visible spectra observed in absorption spectroscopy along with the anatase phase titanium dioxide illustrated in the X-ray diffraction pattern and Raman spectra aided the activation of TAG under visible light irradiation. On addition of TAG, typical SERS bands corresponding to the azo nature of CR were clearly exhibited by C-N symmetric bending modes and C-N stretching modes in the 1160 cm−1–1200 cm−1 region. For CV, the aryl backbone represented by C-C bridge between two phenyl molecules at 1298 cm−1 was recorded in the SERS spectra. Visible light driven degradation of CV and CR in the presence of TAG resulted in high rate constants of 1.09 × 10−2/min and 1.26 × 10−2/min respectively. The reactive oxidative radical species in the photo-degradation reaction of dye was studied by using various scavengers. The observed augmented SERS detection and photocatalytic degradation arises from the synergistic effects of plasmonic properties Ag NPs, anatase TiO 2 and π-π stacking nature of GO. This study suggests that TAG can offer the right 00path way towards an ideal commercial pollutant detection and degradation system. [ABSTRACT FROM AUTHOR]