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In this study, we synthesized CeVO 4 /ZnO nanoheterojunction photocatalyst through hydrothermal-precipitation method. The prepared photocatalyst was characterized by Fourier transform infrared analysis (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) with elemental color mapping (ECM), high-resolution transmission electron microscopy (HR-TEM) with selected area electron diffraction (SAED) pattern, UV-vis diffuse reflection spectroscopy (UV-vis-DRS), BET, and photoluminescence (PL) spectroscopy. The BET surface area of CeVO 4 /ZnO is 10.50 m 2 /g. The photocatalytic activity of CeVO 4 /ZnO nanoheterojunction under solar light was investigated for the degradation of Reactive Orange 4 (RO 4). CeVO 4 /ZnO has been found to be more effective for mineralization of RO 4 than the prepared ZnO at neutral pH. The addition of TBA ( • OH scavenger) contributes a significant decrease in the photodegradation efficiently of the catalyst. Chemical oxygen demand (COD) measurements confirmed the complete mineralization of RO 4. In addition, it found that the photocatalyst was stable and reusable. Graphical abstract.

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.

In the present study, ZnO modified with rare earth oxides GdxMn; M=Mo, V, W) were synthesized by hydrothermal process and their catalytic activity was tested in an oxidative cyclization reaction for the selective synthesis of quinazolinones. The catalysts were characterized by various techniques such as BET surface area analysis, XRD, SEM‐EDX, DSC‐TGA, ICP‐MS and elemental color mapping. 5 wt% Gd2MoO6/ZnO exhibited good catalytic activity and gave 60–91% of Quinazolin‐4(3H) ones in toluene. The catalysts could be reused at least four times without loss of catalytic activity. New protocol was developed for synthesis of Quinazolinones by condensation of anthranilamide with different aldehydes catalysed by rare earth metal oxide namely Gd2MoO6 doped on ZnO. The catalyst was synthesised by hydrothermal method. The catalyst exhibits excellent catalytic activity and was used to synthesis of various quinazoline derivatives. [ABSTRACT FROM AUTHOR]

Abstract Solar photocatalytic process has been shown to be an energy effective and ecofriendly degradation of unwanted pollutants present in the industry wastewater. In this study heterostructured 3 wt% Ho 2 WO 6 /ZnO was synthesized hydrothermally and characterised by surface analytical and spectral techniques. The HR–SEM images reveal that Ho 2 WO 6 /ZnO exists as nanoflakes with mesoporous microstructure clustered together. HR–TEM images reveal that prepared catalyst has hexagonal and spherical structure with uniform particle size. Ho 2 WO 6 /ZnO has more specific surface area (16.44 m2 g−1) than ZnO (11.80 m2 g−1). Reusable Ho 2 WO 6 /ZnO exhibited higher dye photodegradation efficiency, enhanced electrocatalytic activity by methanol oxidation and significant hydrophobicity. [ABSTRACT FROM AUTHOR]

Ever growing research on modified semiconductor oxides made a significant progress in catalytic functional materials. In this article, we report the modification of ZnO photocatalyst by a simple hydrothermal decomposition method utilizing the cheaply available industrial waste fly ash. This modified Fly ash-ZnO photocatalyst was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive spectroscopy (EDS), high resolution transmission electron microscopy (HR-TEM), Atomic force microscopy (AFM), photoluminescence spectroscopy (PL) and diffuse reflectance spectroscopy (DRS). The XRD pattern indicates the presence of fly ash components and the hexagonal wurtzite structured ZnO. TEM images reveal well defined nanorod like structure. Reduction of photoluminescence intensity of Fly ash-ZnO at 418 nm, when compared to, prepared ZnO, indicates the suppression of recombination of the photogenerated electron–hole pair by loaded Fly ash on ZnO. Fly ash-ZnO exhibits enhanced photocatalytic activity for the degradation of azo dyes Reactive Orange 4, Rhodamine-B and Trypan Blue. This catalyst shows higher electrocatalytic activity than ZnO in the oxidation of methanol. Significant hydrophobicity of Fly ash-ZnO reveals its self cleaning property. [ABSTRACT FROM AUTHOR]

Abstract: The activated carbon–zinc oxide catalysts prepared with different portions of activated carbon (AC) have been characterized by diffuse reflectance spectra (DRS), FT-IR, scanning electron micrograph (SEM), X-ray diffraction (XRD) and BET surface area analysis. Changes in some of the physico-chemical characteristics of ZnO have been observed. It is found that these changes correspond with ZnO surface acid–base property. SEM study reveals a perfect ZnO particle distribution on the AC surface in the catalyst with 9%AC content (9AC–ZnO). Adsorption and photodegradation of 4-AP on 9AC–ZnO are much more higher than bare ZnO. The higher efficiency of this photocatalyst is due to the synergistic effect between ZnO and activated carbon. The catalyst is found to be reusable. [Copyright &y& Elsevier]

Developmentof coupled semiconductor oxides makes a significantadvancement in catalytic functional materials. In this article, wereport the preparation of nanobundle-shaped BiVO4–ZnOphotocatalyst by a simple hydrothermal process followed by thermaldecomposition. The photocatalyst was characterized by X-ray powderdiffraction (XRD), high-resolution scanning electron microscopy (HR-SEM),field emission scanning electron microscopy (FE-SEM), energy-dispersivespectroscopy (EDS), transmission electron microscopy (TEM), high-resolutiontransmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy(XPS), photoluminescence spectroscopy (PL), and UV–vis diffusereflectance spectroscopy (DRS). The XRD pattern confirmed formationof monoclinic scheelite BiVO4and the hexagonal wurtzitestructure of ZnO. HR-SEM images show nanobundle-like structure, andthe size of the nanospheres ranges from 20 to 40 nm. BiVO4–ZnO has increased absorption in the UV and visible regionwhen compared to ZnO. The catalytic activity of BiVO4–ZnOwas evaluated by the photodegradation of Acid Violet 7 (AV 7), EvensBlue (EB), and Reactive Red 120 (RR 120). The results revealed thatthe photocatalytic activity of BiVO4–ZnO was muchhigher than that of ZnO, BiVO4, and TiO2–P25under natural sunlight. BiVO4–ZnO is more advantageousthan ZnO and BiVO4in the degradation of AV 7, EB, andRR 120 because it has maximum efficiency at neutral pH 7. BiVO4–ZnO was found to be stable and reusable without appreciableloss of catalytic activity up to four consecutive cycles. The self-cleaningproperty of BiVO4–ZnO has been evaluated using contactangle measurements. Our results provide some new insights on the performanceof solar active photocatalysts on environmental remediation. [ABSTRACT FROM AUTHOR]