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In this article, we report the fabrication of a stable Ag–ZnO–SnO2 nanochain by template free hydrothermal method and its photocatalytic activity for the first time. This composite material represents a potential new class of photocatalysts with enhanced light absorption, hydrophobic and electronic properties of ZnO. This catalyst has been characterized by X-ray diffraction (XRD), high resolution scanning electron microscopy (HRSEM), field emission scanning electron microscopy (FESEM), elemental mapping, energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (DRS) and photoluminescence spectroscopy (PL). XRD and elemental mapping reveal the presence of SnO2 and Ag in the catalyst. Ag–ZnO–SnO2 has increased absorption in the visible region when compared to ZnO. This three component nano junction system exhibits enhanced photocatalytic activity for the degradation of azo dyes, Acid Black 1 (AB 1) and Acid Violet 7 (AV 7) under UV light (365 nm), far exceeding those of the single and two component systems. Ag–ZnO–SnO2 is found to be reusable without appreciable loss of catalytic activity up to four runs. Based on the band gap energies of ZnO and SnO2, a mechanism is proposed for the photodegradation of dyes. Hydrophobicity and photoconductivity of Ag–ZnO–SnO2 have been evaluated. Nanochain exhibiting higher positive photoconductivity can be useful for soliton wave communication as well as solar cell applications. Our results provide some new insights on the fabrication of Ag–ZnO–SnO2 and its performance as an active photocatalyst, self cleaning and conducting material. [ABSTRACT FROM AUTHOR]

In this article, we report the fabrication of a stable Ag-ZnO-SnO2 nanochain by template free hydrothermal method and its photocatalytic activity for the first time. This composite material represents a potential new class of photocatalysts with enhanced light absorption, hydrophobic and electronic properties of ZnO. This catalyst has been characterized by X-ray diffraction (XRD), high resolution scanning electron microscopy (HRSEM), field emission scanning electron microscopy (FESEM), elemental mapping, energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (DRS) and photoluminescence spectroscopy (PL). XRD and elemental mapping reveal the presence of SnO2 and Ag in the catalyst. Ag-ZnO-SnO2 has increased absorption in the visible region when compared to ZnO. This three component nano junction system exhibits enhanced photocatalytic activity for the degradation of azo dyes, Acid Black 1 (AB 1) and Acid Violet 7 (AV 7) under UV light (365 nm), far exceeding those of the single and two component systems. Ag-ZnO-SnO2 is found to be reusable without appreciable loss of catalytic activity up to four runs. Based on the band gap energies of ZnO and SnO2, a mechanism is proposed for the photodegradation of dyes. Hydrophobicity and photoconductivity of Ag-ZnO-SnO2 have been evaluated. Nanochain exhibiting higher positive photoconductivity can be useful for soliton wave communication as well as solar cell applications. Our results provide some new insights on the fabrication of Ag-ZnO-SnO2 and its performance as an active photocatalyst, self cleaning and conducting material.

The development of a heterostructured semiconductor photocatalyst makes a significant advancement in catalytic technologies. Highly crystalline Bi2S3-ZnO nanosheets with a hierarchical structure have been successfully synthesized by a facile sonochemical process and characterized by X-ray diffraction (XRD), high resolution scanning electron microscopy (HR-SEM), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL) and Brunauer-Emmett-Teller (BET) surface area measurements. X-ray powder diffraction (XRD) analysis reveals that the as synthesized product has an orthorhombic phase of Bi2S3 and a hexagonal wurtzite phase of ZnO. XPS analysis shows the presence of the elements Zn, O, Bi and S and their oxidation states. Bi2S3-ZnO has increased absorption in the UV region as well as in the visible region. This heterostructured nano catalyst has a higher photocatalytic activity for the degradation of Acid Black 1 (AB 1) under UV-A light than pure ZnO, Bi2S3 and commercial Degussa P25. The heterojunction in the Bi2S3-ZnO photocatalyst has led to low recombination rates of photoinduced electron-hole pairs and an enhanced photocatalytic activity. Bi2S3-ZnO is advantageous in AB 1 degradation because of its reusability and higher efficiency at neutral pH 7.