For my sample, diffused rings are observed in SAED pattern which is due to the amorphous nature of the sample. In XRD also, amorphous nature is reflected by the presence of broad peaks. But, in TEM image, lattice fringes are observed in some places ( according to my knowledge, lattice fringes will be observed for crystalline materials) . Is it possible like this?
XRD ,SAED pattern and TEM images are attached below.
Sure it is possible. As Aladin Ullrich explained, you get the signal of all your iluminated field. So if your particles are small and thin, you will also get the amorphous rings. However, maby the acquire time is not long, to se some small reflects from those crystalyne particles. Therefore, the diffractions spots that should appear are now (under your conditions) in "shade) of amorphous part.
Well, yes, of course this is possible. In SAD, you get signals from the amorphous regions (including the substrate) and signals from the crystalline regions. Since you are transmitting your sample, also the amorphous substrate under or above your particles contributes to the pattern.
The crystalline regions (visible lattice fringes) should give you more or less sharp spots in the diffraction pattern, finally resulting in rings when enough particles are contributing to the pattern and the particels are oriented randomly.
Does the position of the diffuse ring in SAD correlate with the position of the broad peak in XRD? Check the substrate contribution in TEM and XRD by a reference measurement without particles to be sure that it orginates from your sample!
What kind of sample do you have?
This XRD peak is typical of graphitic carbon. They are usually turbostatic semi-crystalline materials and show HRTEM lattice frings similar to the the image you posted.
There is a wide spectrum of crystallinity for graphitic carbons. For instance carbon nanofibres and nanotubes are fully crystalline with very sharp peak at 25o while Vulcan and active carbons show quite a broad peak at the same angle.
Sure it is possible. As Aladin Ullrich explained, you get the signal of all your iluminated field. So if your particles are small and thin, you will also get the amorphous rings. However, maby the acquire time is not long, to se some small reflects from those crystalyne particles. Therefore, the diffractions spots that should appear are now (under your conditions) in "shade) of amorphous part.
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