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Pd-based catalysts consisting of Pd nanoparticles on nitrogen-doped carbon quantum dots (N-CQDs) modified silica (SiO

CeVO4 as black-light-driven photocatalysts were successfully synthesized by a sol-gel method using citric acid as a complexing agent with subsequent 450–600°C calcination for 2 h. The as-synthesized products were characterized by thermogravimetric analysis (TGA), X-ray diffraction, Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The TGA analysis shows three-step weight losses caused by evaporation and decomposition of adsorbed water, organic compound, citric complex and phase transformation. X-ray diffraction and SEM results show that the samples were specified as tetragonal CeVO4 structure with particle sizes of 50–60 nm, 100–200 nm, 600–1000 nm and 800–1500 nm for 450, 500, 550, and 600°C calcination, respectively. In this research, CeVO4 nanoparticles with 450°C calcination showed the highest photocatalytic activity with •OH radical as the main active species involved in photodegradation of MB under black light irradiation.

0–4 wt% (0–4.11 mol%) Ce-doped MoO3 nanobelts were successfully synthesized by hydrothermal method at 180 °C for 20 h. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show orthorhombic MoO3 and Ce-doped MoO3 nanobelts with >10 μm long, 200–250 nm wide and their growth along the [010] direction. The photocatalytic performance of pure MoO3 and Ce-doped MoO3 nanobelts was investigated through photodegradation of methylene blue (MB) under visible radiation. In this research, 3 wt% (3.08 mol%) Ce-doped MoO3 nanobelts show the highest photocatalytic performance of 94.84% for degradation of MB induced by xenon visible radiation within 50 min.

Heterostructure Ag3PO4/Bi2WO6 nanocomposites were synthesized by precipitation-deposition method. X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectroscopy and UV-visible spectrophotometry revealed that cubic Ag3PO4 nanospheres with

Cl-doped Bi 2 MoO 6 as visible light driven photocatalyst was synthesized by a hydrothermal method. The products were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). In this research, the Cl-doped Bi 2 MoO 6 samples have high crystalline orthorhombic Bi 2 MoO 6 phase. The 3 wt% Cl-doped Bi 2 MoO 6 showed excellent photocatalytic degradation of rhodamine B and followed the first order kinetics model under visible light irradiation.

A simple microwave method has been successfully developed to effectively produce Ag3PO4/Bi2MoO6 nanocomposites. X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) have been employed to determine the phase and morphology of the as-produced products. The photocatalytic activities were tested through the rhodamine B (RhB) degradation under visiblelight radiation. The interaction between cubic Ag3PO4 nanoparticles and orthorhombic Bi2MoO6 nanoplates has been characterized by XRD and TEM. In this research, the as-produced heterostructure Ag3PO4/Bi2MoO6 nanocomposites display effective photogenerated charge transfer between Ag3PO4 and Bi2MoO6 which can improve charge separation. The 10.0 wt % Ag3PO4/Bi2MoO6 nanocomposites showed the highest photocatalytic performance as high as 4.36 times of the pure Bi2MoO6 sample.

In this study, various sizes and chemical compositions of Au/Pd nanoparticles with core/shell structure were successfully prepared by employing a simple successive reduction method without addition of any stabilizer. The optical properties, morphologies, chemical compositions and crystal structures of the synthesized particles were fully characterized by using a combination of UV–vis spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, wavelength-dispersive X-ray spectroscopy, selected area electron diffraction and X-ray diffraction techniques. The catalytic activities of the synthesized Au/Pd nanoparticles for 4-nitrophenol reduction were also investigated and compared with monoatomic Au and Pd nanoparticles. The highest catalytic activity of bimetallic was obtained from AuPd 4 nanoparticles. With comparable size, Au/Pd nanoparticles provide better catalytic activity than those of monometallic Au and Pd. However, lower catalytic activities of Au/Pd nanoparticles are shown compared with that of smaller-size Au nanoparticles. This study also reveals that the size effect of catalysts plays important role on catalytic activity more than only changing their chemical constituents.

ZnO nanoplates were successfully synthesized by hydrothermal method in the solutions containing CTAB. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR). In this research, the as-synthesized samples were hexagonal wurtzite ZnO structure without any impurities and were composed of hexagonal ZnO nanoplates with the vibration mode of Zn–O bonds. The photocatalytic activity of hexagonal ZnO nanoplates showed superior photodegradation of methylene blue (MB) of 94.15 % under UV light irradiation within 80 min. The degradation efficiency of reused hexagonal ZnO nanoplates as photocatalyst indicated that ZnO nanoplates are very stable and reusable under UV light illumination.

PbMoO4 and PbWO4 were successfully synthesized by microwave radiation using different lead salts (acetate, chloride, nitrate and sulfate) and Na2MO4 (M = Mo, W) in propylene glycol. The products were characterized by X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM, TEM), Fourier transform infrared (FT-IR), Raman spectroscopy and photoluminescence (PL) spectroscopy. In this research, morphologies, crystallization and photoluminescence of the products were influenced by the kinetics of anions, including the detection of M–O (M = Mo, W) stretching modes in the (MO4)2− tetrahedrons. Photoluminescence of PbMoO4 synthesized from Pb(NO3)2 and of PbWO4 synthesized from PbCl2 showed the strongest blue emission due to the electronic diffusion in tetrahedrons at room temperature.

CeVO4 nanostructures were successfully synthesized by polyethylene glycol-assisted hydrothermal process. The products synthesized in the solutions containing 0.000–0.020 g polyethylene glycol (PEG) were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). For the use of 0.015 and 0.020 g PEG, the products were uniform and pure tetragonal CeVO4 nanorods growing along the [001] direction. The stretching and bending modes of VO 4 3 - tetrahedrons were detected by Fourier transform infrared (FTIR) and Raman spectroscopy. Methylene blue was used as a representative dye pollutant for evaluating photocatalytic activity under UV radiation. In this research, CeVO4 nanorods synthesized in the solution containing 0.015 g PEG showed the highest photodegradation of 98.03% and the highest apparent rate constant of 0.0128 min−1 within 300 min.

Highly efficient visible-light-driven Ag3PO4/Bi2MoO6 hybrid photocatalysts with different mole ratios of Ag3PO4 were prepared via sonochemical method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that product are cubic Ag3PO4 nanoparticles supported on orthorhombic Bi2MoO6 nanoplates. Under visible light irradiation (>420 nm), the Ag3PO4/Bi2MoO6 photocatalysts displayed the higher photocatalytic activity than pure Bi2MoO6 for the decolorization of rhodamine B (RhB). Among the hybrid photocatalysts, 10% Ag3PO4/Bi2MoO6 exhibited the highest photocatalytic activity for the decolorization of RhB due to the efficient separation of electron–hole pairs.

Copper ferrite (CuFe2O4) nanoparticles were prepared in alkaline solutions containing Cu(NO3)2·6H2O and Fe(NO3)3·9H2O with the pH of 6–12 by microwave-hydrothermal method. The as-prepared products characterized by XRD were specified as cubic CuFe2O4 phase. Average sizes of the CuFe2O4 nanoparticles calculated by Scherrer formula are in the same range as those obtained by TEM analysis. FTIR shows main transmittance band at 585 cm−1, corresponding to stretching mode of tetrahedral complexes. Saturation magnetization, remanence and coercivity were increased with increasing in the particle-size and crystalline degree of the nanoparticles.

Shuttle-like BaMoO4 microstructure has been successfully synthesized from Ba(N03)2·4H20 and Na2MoO4·2H2O as starting materials in ethylene glycol solvent containing 20 mL 5 M NaOH by microwave radiation at 180 W for 30 min. The as- synthesized BaMoO4 product was characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectrophotometry, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and photolumines­cence (PL) spectroscopy. XRD patterns revealed that the products was tetragonal BaMoO4 phase. SEM and TEM characteriza­tion showed that the product had a shuttle-like BaMoO4 microstructure. PL of the shuttle-like BaMoO4 microstructure showed a maximum emission at 466 nm excited by 280 nm wavelength.