Good job. But Origin already has a great built-in fitting tool. Yes, it does not give x-intercept directly. But for this purpose one can create his/her own linear fit function by adding x-intercept as DERIVED PARAMETER. In linear fitting, the curve is y=ax+b, then associated bandgap is x-intercept: E_g=-b/a.
Thankyou so much for the video!! fastastic. is there other methods to confirm about the band gap of the compound? if so please highlight. thankyou in advance
hello. for the indirect part, the starting point of y axis is not equals to 0. but for the direct part, you mentioned in the video we need to always keep the starting point of y axis zero. so is the starting point 0 matter for the indirect part?
Thank you for the effort but i 'd like to draw your attention to the fact that the Taux plot of certain materials could present the linear part and the y-axis strats from "0" for both direct and indirect transitions. What would you pick in this situation ?!
it is good for solar cells having increased band gap because it allows more absorption of charges while in batteries low band gap materials are preferable
Thanks for sharing, how can i get the UV Absorbance/Wavelength data of TiO2 or TiO2/ZnO hybrid nanoparticle, can i just dissolve/disperse it in water and scan using the UV or i have to make a Solid Sample, Thank you
I wanted to aske that first we need to put both value in tauc"s formula and then find out from nature of graph that our material has either direct or indirect BAND GAP? BTW your tutorial are useful for my research work. Thank you
I wonder why it can identify the direct or indirect bandgap just from the n value, what's the theory behind it? and sometimes, I can see straight line part both from n=2 and 1/2, confuse me:D
Hi. I have a question. Can a material have both direct and indirect bandgap? Is it possible let's say the nature of the material is direct but the indirect comes from defects? TIA!
The energy gap of 3.2 eV for TiO2 suggests the presence of Anatase wich has indirect band gap while Rutile with Eg=3.0 eV can have direct band gap alignment. I expect some dopants can modify the band alignment of Anatase otherwise i don't understand the results. Any help on clarifying this issue?
X-ray absorption near-edge structure (XANES) from an X-ray absorption spectrum can tell you this by looking at the pre-edge peak position and intensity. X-ray photoelectron spectroscopy (XPS) can also tell you oxidation state of all elements present on the surface of your material.
If I want get absorbance as a function of wavelength. For preparing the samples, what is the suitable thickness of Tio2, MnO2, SiN or a-Si ... they should be thicker than a certain amount?
Thanks for all help. i really appreciate your videos. There is a way to obtain data on the chemical states of the elements in a semiconductor or a nanoparticulate composite by origin?
Yes they do, only If the concentration is too low or too high. In these causes, the material will not obey the Beer lambert's law and as a result will give you wrong value of the bandgap energy.
Hi! You did a mistake in the lecture. n = 1/2 for direct allowed transitions and n = 2 for indirect allowed transitions. In the video, you wrote it vice versa.
This option is visible in all the latest versions of OriginLab including 9.0 and above. However, in versions below 9.0, you can access this option by clicking on any column and then goes to Input column values option
Hello, thanks for an informative video. Can you also explain how can we measure the energy band gap from the specular reflectance data collected from UV-VIS? I have a formula alpha = (1-R)^2/(2R). Using the reflectance data, we can calculate alpha without the need of thickness and plot (alpha h v)^2 vs (hv). This is basically for the diffuse reflectance data but I am not sure if it is applicable for specular reflectance. Also, From the tauc plot (alpha h v)2 vs (hv), how can we measure the energy band gap if we have multiple peaks? I mean it’s difficult to choose a point to extrapolate if we have multiple peaks. So, how can we decide?
Amazing sir learn lots of thing from this video. Even now i dont need to discuss with this thing with ny supervisor. Great job highly appreciated
Glad it was helpful!
Good job. But Origin already has a great built-in fitting tool. Yes, it does not give x-intercept directly. But for this purpose one can create his/her own linear fit function by adding x-intercept as DERIVED PARAMETER. In linear fitting, the curve is y=ax+b, then associated bandgap is x-intercept: E_g=-b/a.
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Sir put up the video Vickers microhardness testing.how I calculated work hardening coefficient or Meyer index value
Very informative video and nice BGM. Keep it up and make more videos.
Thankyou so much for the video!! fastastic. is there other methods to confirm about the band gap of the compound? if so please highlight. thankyou in advance
hello. for the indirect part, the starting point of y axis is not equals to 0. but for the direct part, you mentioned in the video we need to always keep the starting point of y axis zero. so is the starting point 0 matter for the indirect part?
Consice and clear explanation sir, thanks for the video
Glad you liked it
Thank you for the effort but i 'd like to draw your attention to the fact that the Taux plot of certain materials could present the linear part and the y-axis strats from "0" for both direct and indirect transitions. What would you pick in this situation ?!
Thanks for wonderful explanation
Please how I calculate absorbance coefficient if I used solution samples to testing UV-visible absorbance?????
Sir I have a question, for thin films solar cells is increasing badgap good or decreasing?
it is good for solar cells having increased band gap because it allows more absorption of charges while in batteries low band gap materials are preferable
excellent video
well done bro u have solved my big problem. Really nice explain.
Thanks for sharing, how can i get the UV Absorbance/Wavelength data of TiO2 or TiO2/ZnO hybrid nanoparticle, can i just dissolve/disperse it in water and scan using the UV or i have to make a Solid Sample, Thank you
Very nicely done
I wanted to aske that first we need to put both value in tauc"s formula and then find out from nature of graph that our material has either direct or indirect BAND GAP? BTW your tutorial are useful for my research work. Thank you
I wonder why it can identify the direct or indirect bandgap just from the n value, what's the theory behind it?
and sometimes, I can see straight line part both from n=2 and 1/2, confuse me:D
Hay sir, many thanks for your video. My sample is liquid, do yo know how to get the thickness ?
Very nice video
Thanks
Very helpful. Thank you. Keep up the good work.
Glad it was helpful!
Thanks a lot sir
Nice and helpful.
Hi. I have a question. Can a material have both direct and indirect bandgap? Is it possible let's say the nature of the material is direct but the indirect comes from defects? TIA!
The energy gap of 3.2 eV for TiO2 suggests the presence of Anatase wich has indirect band gap while Rutile with Eg=3.0 eV can have direct band gap alignment. I expect some dopants can modify the band alignment of Anatase otherwise i don't understand the results. Any help on clarifying this issue?
in which calculation should i put my smoke thickness?
How to draw tauc plote for thin film
How can we find out the nature of metal ion, the oxidation state of the metal ion, and its coordination? Please help me to know that
X-ray absorption near-edge structure (XANES) from an X-ray absorption spectrum can tell you this by looking at the pre-edge peak position and intensity. X-ray photoelectron spectroscopy (XPS) can also tell you oxidation state of all elements present on the surface of your material.
If I want get absorbance as a function of wavelength. For preparing the samples, what is the suitable thickness of Tio2, MnO2, SiN or a-Si ... they should be thicker than a certain amount?
YOU HAVE WEONGLY FITTED THE CURVE
Thank You
Thanks for all help. i really appreciate your videos.
There is a way to obtain data on the chemical states of the elements in a semiconductor or a nanoparticulate composite by origin?
how to calculate the absorption coefficient(m^-1) and refractive index spectrum from the absorbance (au) spectrum.
many thanks
hi, thanks so much for the videos, does the concentration effect on the calculation and the bandgap values? Mnay thanks
Yes they do, only If the concentration is too low or too high. In these causes, the material will not obey the Beer lambert's law and as a result will give you wrong value of the bandgap energy.
thank you bro
Welcome
Kindly post bandgap of BeO nanoparticles
Hi!
You did a mistake in the lecture.
n = 1/2 for direct allowed transitions and
n = 2 for indirect allowed transitions. In the video, you wrote it vice versa.
Sorry. it is my mistake). You wrote n, not 1/n)
THANK YOU VERY WELL
THNKU SIR
You are welcome
Good Informative video...this is really helpful for me.
can you tell me how you add the "F(x)=" in you origin?
This option is visible in all the latest versions of OriginLab including 9.0 and above. However, in versions below 9.0, you can access this option by clicking on any column and then goes to Input column values option
@@nanoworld6122 I am doing exactly what you said bt. i want it to be visible in front also. I am using OriginPro 9.0.0 SR2
sorry, I don't know about SR2 version.
Hello, thanks for an informative video. Can you also explain how can we measure the energy band gap from the specular reflectance data collected from UV-VIS? I have a formula alpha = (1-R)^2/(2R). Using the reflectance data, we can calculate alpha without the need of thickness and plot (alpha h v)^2 vs (hv). This is basically for the diffuse reflectance data but I am not sure if it is applicable for specular reflectance. Also,
From the tauc plot (alpha h v)2 vs (hv), how can we measure the energy band gap if we have multiple peaks? I mean it’s difficult to choose a point to extrapolate if we have multiple peaks. So, how can we decide?
Please respond
tthank you
You're welcome
For me i obtained the linear part in direct and indirect plots. I find the same results in the litterature.
Yes, sometimes researcher report both.
It is a powder sample equation
2.303 means wat
Please watch this video
ua-cam.com/video/tbyJjCMkDtc/v-deo.html