Nanostructured NiSb2O6 samples were synthesized via solid state reactions at the reaction temperatures of 600, 700 and 800 °C using Sb2O3, Ni(CH3COO)2.2H2O and Ni(NO3)2.6H2O as raw materials. Parameters of reaction temperature and raw materials types were investigated for the crystal phase growth study. The synthesized nanomaterials were characterized by X-ray powder diffraction (XRPD) technique, fourier-transform infrared (FTIR) spectroscopy. Brunauer–Emmett–Teller (BET) and Barrett-Joyner-Halenda (BJH) methods were used to investigate the textural properties of the obtained samples. Rietveld analyses showed that the obtained materials were crystallized well in the tetragonal crystal structure with the space group of P42/mnm. The lattice parameters of the targets were about a = b = 4.64 Å and c = 9.22 Å. The data revealed that the crystal phase purity of the as-synthesized nanomaterials was increased with increasing the reaction temperature from 600 to 800 °C. Besides, the data indicated that the synthesis reactions using Ni(NO3)2.6H2O generated a better crystalline growth and purity compared to Ni(CH3COO)2.2H2O raw material in a certain reaction temperature. The morphologies of the synthesized materials were studied by field emission scanning electron microscopy (FESEM) technique. The FESEM images showed that the homogeneity of the synthesized powder was improved when Ni(NO3)2.6H2O was used as raw material. Ultraviolet-visible spectra showed that the synthesized NiSb2O6 nanomaterials had strong light absorption in the ultraviolet light region. The calculated direct optical band gaps tendency showed that the band gaps were increased with increasing the reaction temperature. تفاصيل المقالة

As reported in our previous work, Sr3Al2O6 nano powders were synthesized by a one-step solid state reaction using Al﴾NO3)3.6H2O, Sr﴾C2H3O2)2 and Sr﴾NO3)2 at 800 and 900 ̊C for 8 h. For the synthesis of Sr3MxAl2O6+δ ﴾M= Sm3+, Eu3+, Ho3+ and Yb3+) nano powders, Al﴾NO3)3.6H2O, Sr﴾NO3)2, Eu2O3, Ho2O3 and Yb2O3 were used at 800 ̊C for 8 h. In the present work, the photocatalytic performance of Sr3MxAl2O6+δ ﴾M=None, Sm3+, Eu3+, Ho3+ and Yb3+) nanomaterials were investigated for the degradation of Malachite Green (MG) water pollutant in aqueous solution under direct white visible light irradiation with the light power 40 W. The optimum conditions were obtained by design expert software for (5%) Al2O3 - (95%) Sr3Al2O6 (S1). It was found that the optimum conditions were 0.2 mL of H2O2, 20 mg of catalyst, and 40 min. The initial volume and concentration of MG solution were 150 mL and 100 ppm, respectively. It was found that Sr3Al2O6 had excellent efficiency under the optimized conditions at the presence of direct visible light irradiation. The degradation yield in the optimized conditions was 100 %. تفاصيل المقالة

Nanostructured As2Ni3O8 samples were synthesized via facile solid state reactions at 850 and 950 °C for 8h using As2O3, Ni(CH3COO)2.2H2O and Ni(NO3)2.6H2O raw materials. The synthesized nanomaterials were characterized by powder X-ray diffraction (PXRD) technique and fourier-transform infrared (FTIR) spectroscopy. The rietveld analyses showed that the obtained materials were crystallized well in monoclinic crystal structure with the space group P121/c1. The lattice parameters of the targets were about a = 5.76 Å, b = 9.54 Å and c = 10.18 Å with β = 92.95 °. It was found that nickel nitrate created a highly crystalline and pure As2Ni3O8 structure. However, nickel acetate created the target with lower purity and crystal phase growth; it produced the samples with smaller crystallite sizes. Reaction temperature changing showed that the parameter affected on the crystal growth of the obtained materials. The morphologies of the synthesized materials were studied by field emission scanning electron microscopy (FESEM) technique. Ultraviolet-visible spectra showed that the synthesized As2Ni3O8 nanomaterials had strong light absorption in the ultraviolet - visible light region. The direct optical band gaps were 2.6 and 2.5 eV for S1 and S3, respectively. The data showed that the band gaps were decreased by increasing the reaction temperature. This is due to the increasing the crystallite sizes of the obtained materials. تفاصيل المقالة

Nanostructured Bi2Sn2O7 and Bi2MxSn2O7 ﴾M = Y3+, Eu3+, Gd3+ and Yb3+) nanomaterials were synthesized by conventional one-step solid state crystal growth reactions among Bi(NO3)3, SnCl2 and M2O3 raw materials at 800 ̊C for 10 and 15 h. The doped nanomaterials were synthesized to study the capacity of the crystal system to locate each of the dopant ions into the crystal system cavities. The synthesized nanomaterials were characterized by powder X-ray diffraction (PXRD) technique. Rietveld analysis showed that the obtained materials were crystallized well in orthorhombic crystal structure with the space group Aba2. The PXRD data revealed that dopant ion type had a considerable influence on the crystal phase purity of the obtained targets. The morphologies of the synthesized materials were studied by field emission scanning electron microscopy (FESEM) technique. Ultraviolet-visible spectra analysis showed that the synthesized nanomaterials had strong light absorption in the ultraviolet light region. Photocatalytic performance of the synthesized nanomaterials was investigated for the degradation of pollutant Malachite Green under solar light condition. The optimum conditions were modeled and obtained by design expert software for Bi2Sn2O7 that was synthesized at 800 ̊C for 10 h which were 0.06 mL H2O2, 12 mg catalyst and 40 min for the removal of 50 mL of 40 ppm MG solution. The degradation yield in these conditions was 100 %. The photocatalytic degradation fitted to the Langmuir–Hinshelwood kinetic model. As a result of the model, the kinetic of degradation followed a pseudo-zero-order kinetic model. تفاصيل المقالة

Nanostructured As2Ni3O8 samples were synthesized via facile solid-state reactions at 850 and 950 °C for 8h using As2O3, Ni(CH3COO)2.2H2O and Ni(NO3)2.6H2O raw materials. The synthesized nanomaterials were characterized by powder X-ray diffraction (PXRD) technique and fourier-transform infrared (FTIR) spectroscopy. The rietveld analyses showed that the obtained materials were crystallized well in monoclinic crystal structure with the space group P121/c1. The lattice parameters of the targets were about a = 5.76 Å, b = 9.54 Å and c = 10.18 Å with β = 92.95 °. It was found that nickel nitrate created a highly crystalline and pure As2Ni3O8 structure. However, nickel acetate created the target with lower purity and crystal phase growth; it produced the samples with smaller crystallite sizes. Reaction temperature changing showed that the parameter affected on the crystal growth of the obtained materials. The morphologies of the synthesized materials were studied by field emission scanning electron microscopy (FESEM) technique. Ultraviolet-visible spectra showed that the synthesized As2Ni3O8 nanomaterials had strong light absorption in the ultraviolet-visible light region. The direct optical band gaps were 2.6 and 2.5 eV for S1 and S3, respectively. The data showed that the band gaps were decreased by increasing the reaction temperature. This is due to the increasing the crystallite sizes of the obtained materials. تفاصيل المقالة