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Sherrer formula

XRD data for selected samples are shown in Table 1. The interplanar spacings, doo2 and doo4, were evaluated from the positions of the 002 and 004 peaks respectively by applying Bragg s equation. The crystallite size Lc along the c-axis was calculated from the 002 peak using the Sherrer formula... [Pg.415]

The supported layers obtained after treating at 500°C exhibited crystallized structures (anatase for titania and a tetragonal metastable form for zirconia) and revealed a very fine texture from TEM observation. For Ti with a Ti/acac ratio = 1, grains with defined faces can be observed whose size is around 20 nm. For Zr with a Zr/acac ratio = 2, a finer texture was obtained than with titania, with a mean grain size of around 4 nm. In the two cases, powder x-ray diffraction (Sherrer formula) was used to measure an individual crystal size, which is in good accordance with TEM observations. For the zirconia membrane the N2 adsorption and desorption isotherm in Fig. 18a shows a micro-porous domain with a 1.7 nm centered pore size distribution (Fig. 18b). [Pg.521]

It is considered that two diffraction peaks at /-spacings of 0.52 nm (100) and 0.23 nm (101) are attributed to the crystalline perfluorinated backbone of Nation 115. Others (0.44,0.365,0.264, and 0.170 nm) are assigned to ZrP crystal in the composite membrane, because these peaks matched up with the typical peaks of crystalline ZrP in literatures. " At the same time, these diffraction peaks also agreed well with the XRD pattern of ZrP powder. According to the Debye-Sherrer formula, the mean particle size of ZrP can be calculated to be about 5.0 nm from two peaks at 0.264 and 0.17 nm. The EDX pattern effectively verified the presence of ZrP. It was also found that the atomic ratio of P and Zr was 1.74, which is close to 2, the value in the molecular formula Zr(H2P04)2. [Pg.435]

The average grainsize was determinedby means ofthe Sherrer s formula. Moreover, the nanopowders were investigated by means of transmission electron microscopy (TEM) (JEM 2010, JEOL). For the TEM studies the powders were dispersed in distilled water and a drop of suspension was placed on a copper grid with a transparent polymer and dried. Elemental analysis was performed by inductively coupled plasma (ICP) spectrometer, (Spectroflame Modula, Spectro). The in vitro test were performed leaving the nanopowders for 30 days in three different solutions distilled water, SBF (simulated body fluid [17]) and SBF added of citric acid (0.08 M), at 60°C. This temperature was chosen to better evaluate the powder behaviour under the most extreme conditions. [Pg.339]

Average noble metal particles sizes are determined by X-ray line broadening, corrected for diffractometer angular divergence (Warren-corrected Sherrer s formula (5)). [Pg.832]


See other pages where Sherrer formula is mentioned: [Pg.315]    [Pg.379]    [Pg.1342]    [Pg.315]    [Pg.379]    [Pg.1342]    [Pg.243]    [Pg.399]    [Pg.658]   
See also in sourсe #XX -- [ Pg.406 ]

See also in sourсe #XX -- [ Pg.406 ]

See also in sourсe #XX -- [ Pg.406 ]




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