Search results

From Fig. 2(a), (b), It indicates that the particles product is wurtzite (hexagonal) ZnO structure (JCPDS card 76-704) as KCl concentration below 0.02M.
ZnO intensity becomes slight and Zn5(OH)8Cl2·H2O (JCPDS card number 07-155) spectrum increase more and more.
The XRD patterns in Fig.2 (f), (g) indicate that the products are the mixture of Zn5(OH)8Cl2·H2O and Zn (JCPDS card 87-173) at high KCl concentration (0.8M, 3.2M respectively).

Their analysis leads to a number of important conclusions.
The crystallographic parameters are closed to the pure FCC germanium crystal system with a = 5.658 Å (JCPDS card no. 04-0545).
This crystal system is similar to pure trigonal Sb system (JCPDS card no. 35-0732) having the lattice parameters a = b = 4.307 Å, c = 11.273 Å, α = β = 90°, and γ = 60°.
Similar structure presents for example the Fe3Mn4Ge6 system (JCPDS card no. 71-0017).

Introduction In doping of the zinc aluminate may occur for Al+3 and Zn+2 ions replacements, where the charge and ionic radius, and coordination number should be taken into consideration.
Thus, the hope is that ions with valence II and coordination numbers smaller displace the divalent zinc ions, and ions with valence III and higher coordination numbers to replace the Al3+ [1-4].
For phase identification program was used (Pmgr) from Shimadzu and obtain crystallographic patterns of the chips was accessed the database JCPDS.
It can be observed diffraction patterns for both the formation of a major phase of cubic spinel crystalline phase normal ZnAl2O4 according to JCPDS 05-0669 card, and also peaks of the secondary phase EuAlO3 according to JCPDS 30-0012 card.

Results and Discussion Figure1 shows the XRD patterns for the 900 ˚C annealed SiO2 (a), SiO2/ Ca10(PO4)6(OH)2 (b), SiO2/Ca10(PO4)6(OH)2:Eu3+ (c) and pure Ca10(PO4)6(OH)2 (d) powder samples as well as the JCPDS card (No. 74-0565) for Ca10(PO4)6(OH)2 (e) as a reference.
For SiO2 particles annealed at 900 ˚C Figure 1 X-ray diffraction patterns for SiO2 (a), SiO2/Ca10(PO4)6(OH)2:Eu3+ core-shell particles(b), SiO2/Ca10(PO4)6(OH)2 core-shell particles (c), pure Ca10(PO4)6(OH)2 powders (d) and the JCPDS card74-0565 for Ca10(PO4)6(OH)2 (e) All the samples were obtained after annealing at 900 ˚C for 2h.
(Figure 1a), no diffraction peak is observed except for a broad band centered at 2θ = 22.00o, which is the characteristic peak for amorphous SiO2 (JCPDS 29-0085).
For the SiO2/Ca10(PO4)6(OH)2 and SiO2/ Ca10(PO4)6(OH)2:Eu3+ core-shell particles annealed at 900 ˚C (Figure (b)(c)), apart from the broad band from amorphous SiO2 (2θ = 22.00o), diffraction peaks at 2θ = 10.8 o (100), 25.9o (002), 28.9 o (210), 31.8 o (211), 32.2 o (112), 32.9 o (300), 34.1 o (202), 39.8 o (130), 46.7 o (222), 49.5 o (213) and 50.5 o(321) are present, all of which can be indexed to the Ca10(PO4)6(OH)2 (JCPDS Card 74-0565, Figure 1(e).
The excitation spectrum (Figure 3(a)) of Eu3+ ion that obtained by monitoring the Eu3+ 5D0- 7F2 luminescence at 613 nm consists of a broad band with a maximum at 260 nm and a number of line excitation peaks (strong two are at 398 nm for 7F0- 5L6 and at 466 nm) of Eu3+.

Introduction Hafnium oxide (HfO2) and zirconium oxide (ZrO2) thin films have attracted great interest, because of their large number of potential applications in optical coatings and microelectronics.
The sizes of the nanocrystalline particles are in the range of 6 to 13 nm, when the number of layers and the temperature were increased, the particle size was increased.
[9] Joint Committee on Powder Diffraction Standards (JCPDS); Card No. 043-1017
[10] Joint Committee on Powder Diffraction Standards (JCPDS); Card No. 050-1089.

With small pulses numbers, the XRD pattern confirms the formation of CdO with three peaks (111), (200), and (220).
The bandgap of the synthesized films reduces by rising the number of laser pulses.
The patterns of XRD analysis of the films with thickness (235, 250, and 270 nm) show that the synthesis CdS films have polycrystalline and hexagonal nanostructure with three notable peaks along (100), (002), and (101) planes which are matched with standard data card of CdS (JCPDS card no. 41-1049) and preferentially orientated along (101) plane.
The lattice constants (a) and (c) are close to the lattice constant values (a= 4.1 Ǻ, c= 6.7 Ǻ) of standard data card of CdS (JCPDS card no. 41-1049).
This means that as the number of laser pulses increases the bandgap reduce.

These formations originate from a low number of macroparticles formed during the CAD process which are enhanced in the film forming mounds or delaminate forming craters.
In any case their number is very limited and is not expected to influence the performance of the coating.
In all cases the peaks fall between those for aluminum nitride (JCPDS Card No. 25-1495) and chromium nitride (JCPDS Card No. 77-047) [21], which implies complete solubility of chromium, aluminum and nitrogen in the B1 lattice [22].
GIXRD spectra of the CrAlSiN/AlSiN multilayer film (The peak identification was made using PDF #251495 for AlN and PDF #77047 for CrN JCPDS cards [21]).
[20] http,//www.platit.com/p80 [21] PC Powder Diffraction Files, JCPDS-ICDD, 2003

The crystalline diffraction lines observed for the C/ZnO composite correspond to ZnO phase with hexagonal symmetry and space group P63mc (JCPDS 36-14-51 card) [13].
For the C/TiO2 composite, the diffraction lines observed are attributed to the TiO2 anatase with tetragonal symmetry and space group I41/amd (JCPDS 22-1272 card) [13].
However, it is possible to obtain information such as the topography of the sample (contrast function of the relief), as well as image of composition (contrast as a function of atomic number of the elements present in the sample) [21].
[13] JCPDS – International Centre for Diffraction Data.
Copyright© JCPDS-ICDD. 2000

Fig.2 The Scanning electron microscope (SEM) photograph of SrAl2O4:Eu2+ The SEM photograph of SrAl2O4:Eu2+ powder indicated that the product presented crystal, fluey and foam shape, at the same time there are a great number of bores in the particles, and the surface of particles embodied irregular shape.
This phenomenon was caused by large numbers of  gasses, for example alkaline, nitrogen, carbon dioxide, nitric oxides and water gas which were produced during preparing.
XRD patterns showed well resolved reflections, indicating the formation of monoclinic structure SrAl2O4:Eu2+ as the main phase comparing to JCPDS Card, which belongs to P21 space grouping.
Some minor changes in lattice parameters were detected, the reason was that urea was breaked down under higher temperature, and produced a great number of ammonia, which introduced OH-, a little of alkalescence aluminate, there was a little of SrAl3O5( OH)  in the sample powder according to JCPDS Card, which belonged to orthorhombic structure system.

From it we can see there is a kind of hierarchical rod-like structure except for a large number of cone-like rods and particles.
When 2θ ranges from 20° to 70°, aside from diffraction peak of the steel (JCPDS card number 65-4899), we only find diffraction peak of wurtzite (JCPDS card number 80-75), and diffraction peak of ZnO (002) is far stronger than others, which shows ZnO cone-like rods and hierarchical structures preferentially grow along the C-axis.