I am doing Research on tin and tin oxide nanoparticles using laser ablation method in different liquids. I have varied the energy and fixed the time and wavelength. The XRD result shows different planes appear when i increased energy from 30 mJ to 60 mJ. The intensity is also varying. My EDX result shows that oxide ratio increases and tin ratio decreases with the increase of laser energy. However my XRD result shows opposite relation. I am uploading my result for samples prepared in ethanol....Please help me in understanding this result
To start with I would repeat your XRD and obtain better data. These diffractograms appear to have poor signal/noise; your peaks of interest are barely above the background level. It may help us also if we can see your EDX results.
Maybe the difference is caused by different origin of EDS and XRD signal? If your particles are not crystalline, they will appear in EDS but not in XRD. But it could be also because of small size of the particles, interferring with your results (both XRD and EDS could be problematic for non-experienced user due to large interaction voluem in EDS and strong background in XRD)...
To start with I would repeat your XRD and obtain better data. These diffractograms appear to have poor signal/noise; your peaks of interest are barely above the background level. It may help us also if we can see your EDX results.
I see than both diffraction patterns are quasi identicals; the sample at 30 mJ is a little more crystalline (stronger and weel defined peaks). The difference between XRD and EDX could be that tin oxide is in higher amount but their crystallinity is poor. No contradictions in my opinion.
Best regards,
Pedro
Your XRD diffractograms do not fulfill statistically the standard data. The relative intensity is too low. For obtaining higher intensity you must double the holding time at least 2 s for every step size. The XRD data showed poor crystallinity. Logically when laser energy is lower the result phase should be dominated by SnO because the melting point of SnO (1080C) is lower than SnO2 (1630C). In your case it looks like contradiction. But in my opinion concerning the quality of your data, both diffraction patterns are the same. It is not easy to analyze the different of both data.
The laser beam high energy source which are Directly proportionall to frequency or Inversely Proportional to wavelength, when it applied on the material the crystal lattice will be changed with respect its value. In radiometry, radiant intensity is the radiant flux emitted, reflected, transmitted or received, per unit solid angle, and spectral intensity is the radiant intensity per unit frequency or wavelength, depending on whether the spectrum is taken as a function of frequency or of wavelength. These are directional quantities. Hence XRD shows different plane of different intensity for samples prepared using LA. I hope you satified with my answer.
How about slow your scan speed and compare again your results? It seems the noise is very heavy and covered the differences.
Sample texure, densit, composition and particle morphology will not be the same by different methods. Add to this the noise factor in XRD. Reduced noise, slower scan rate will improve the situation.
- Badges
- Science method
- Similar topics
- Methodology
- Crystallography
- X-ray Diffraction