Structure composition correlation in KNN–BT ceramics – An X-ray diffraction and Raman spectroscopic investigation

K-Ta mixed oxides photocatalysts have been prepared by impregnation followed by calcination. The influence of the reaction temperature (450°C–900°C) on the phase formation, crystal morphology, and photocatalytic activity in hydrogen generation of the produced materials was investigated. The detailed analysis has revealed that all products exhibit high crystallinity and irregular structure. Moreover, two different crystal structures of potassium tantalates such as KTaO3and K2Ta4O11were obtained. It was also found that the sample composed of KTaO3and traces of unreacted Ta2O5(annealed at 600°C) exhibits the highest activity in the reaction of photocatalytic hydrogen generation. The crystallographic phases, optical and vibronic properties were examined by X-ray diffraction (XRD) and diffuse reflectance (DR) UV-vis and resonance Raman spectroscopic methods, respectively. Morphology and chemical composition of the produced samples were studied using a high-resolution transmission electron microscope (HR-TEM) and an energy dispersive X-ray spectrometer (EDX) as its mode.

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X-ray diffraction and Raman spectroscopic studies of Zn-substituted carrboydite-like compounds

Materials Chemistry and Physics ◽

10.1016/j.matchemphys.2005.12.028 ◽

2006 ◽

Vol 100 (1) ◽

pp. 174-186 ◽

Cited By ~ 14

Author(s):

Yu-Hsiang Lin ◽

Moses O. Adebajo ◽

J. Theo Kloprogge ◽

Wayde N. Martens ◽

Ray L. Frost

Keyword(s):

Spectroscopic Studies ◽

X Ray Diffraction ◽

X Ray ◽

Raman Spectroscopic

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X-ray Diffraction and X-ray Absorption Near-Edge Structure Spectroscopic Investigation of Hydroxyapatite Formation under Slightly Acidic and Neutral pH Conditions

ACS Earth and Space Chemistry ◽

10.1021/acsearthspacechem.9b00089 ◽

2019 ◽

Vol 3 (10) ◽

pp. 2266-2275

Author(s):

Kai-Yue Chen ◽

Yuji Arai

Keyword(s):

Spectroscopic Investigation ◽

X Ray Diffraction ◽

Edge Structure ◽

X Ray ◽

Neutral Ph ◽

Ph Conditions ◽

X Ray Absorption ◽

Hydroxyapatite Formation

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Raman Spectroscopic and X-ray Diffraction Studies on Concentrated Aqueous Zinc (II) Bromide Solution at High Temperatures

Zeitschrift für Naturforschung A ◽

10.1515/zna-1992-0308 ◽

1992 ◽

Vol 47 (3) ◽

pp. 485-492 ◽

Cited By ~ 2

Author(s):

Toshiyuki Takamuku ◽

Mikito Ihara ◽

Toshio Yamaguchi ◽

Hisanobu Wakita

Keyword(s):

Diffraction Data ◽

Broad Band ◽

Molar Ratio ◽

X Ray Diffraction ◽

X Ray ◽

Raman Spectroscopic ◽

X Ray Scattering ◽

Bromide Solution ◽

Stretching Vibration ◽

Increasing Temperature

Abstract Raman and X-ray scattering experiments have been performed on an aqueous zinc (II) bromide solution with molar ratio [ H2 0] / [ ZnBr2 ] =10 at 25 to 140 °C. The intensity of the totally symmetric Zn - Br stretching vibration (ν1) for the dibromozinc(II) complex increased with increasing temperature while that for the tetrabromo complex decreased. A broad band assigned to the symmetric Zn - O stretching vibration ( ν1 ) for the aqua zinc (II) ion decreased in intensity with increasing temperature. The X-ray diffraction data revealed that the average number of the Zn - Br interactions within the zinc (II) bromo complexes does not change with temperature, whereas the number of Br ··· Br nonbonding interactions within the complexes decreases from 1.8 at 25 °C to 1.5 at 100 °C. From both Raman and X-ray data it is concluded that with increasing temperature the dibromo species is favored, whereas the tetrabromo and aqua zinc(II) species are unstable in the solution. The analysis of the X-ray diffraction data has shown that the mean Zn - Br bond length within the zinc (II) bromo complexes shortens gradually with increasing temperature, accompanied with an increase in the interligand Br ···Br distance. This finding suggests that the Br - Zn - Br bond angle increases with decreasing Zn - Br distance for the lower zinc(II) bromo complexes. The equilibrium shift of the zinc (II) bromo complexes with temperature is discussed on the basis of ion-ion, ion-water, and water-water interactions

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