Carbon Quantum Dots: Hydrothermal Synthesis and characterization
Вставка
- Опубліковано 22 кві 2020
- In this video, you will see how to make Carbon Quantum Dots (CQDs) using Hydrothermal Method using organic ingredients such as orange juice. You will also see how we can use Transmission Electron Microscopy (TEM) to see the super tiny CQDs particles and measure the size of the particles.
#carbon #carbondots #quantum #quantumdot #biosensing #bioimaging #drugdelivery #postdoctoralresearch #phdlife #research #biomedical_engineering #fluorescent #nanomaterials #nanomedicine #researchscholar #researchpublication
This made my day. Thank you.
Incredible video, thanks
Thanks for your efforts
Thank you for your insights
It helped me a lot with my assignment 🌷
Great video. Thanks for showing everything in detail!
Let me know if you have any questions.
@@NanoAustralia Thanks, I may take you up on that offer.
This video is very helpful and effective for beginners like me to understand well about synthesis and characterization of CQDs, please keep going and share your knowledge with us. Thank you 😊
Hi Anam, Thank you so much for your beautiful comments. I'm glad to hear such amazing feedback! Please let me know if you have any questions regarding the CQDs. Also please watch the other video I posted for using CQDs for biosensing applications. Cheers.
The video was extremely helpful and easily understandable. Thank you sir.
Thanks so much for the comment Sumon!
Great 👌🏻Thanks a lot for providing useful information 🌺
Please let me know if you have any questions!
thank you so much for giving this knowledge ...keep uploading like this... and also explain like this about pyrolysis
Thanks for your feedback!
Thank you so much sir😊
It was a wonderful video!!!
Im glad it helps :)
Thank you sir
thank you Dr
. this really helpful since i need to synthesis CQDs .
let me know if you have any question :)
👌👌
Thank you
thank you so much sir, Very nice explaination, easy to understand. i like video. well done sir.
Thanks!
Hi very well made videos and i'm curious to know how you extracted ascorbic acid from orange juice
We purchased the extracted Ascorbic Acid from Sigma as we wanted to have the highest purity for the synthesis.
I just learned about CQD, I have a few questions to ask. Really thank you if you answer them:
- The PL emission spectra of CQDs are not separate like semiconductor QDs, but they overlap and only change the strength and weakness of the emission peak. Why is this?
- What effect does a wide particle size distribution such as 9-23 nm versus a narrow size distribution of 3-7 nm have on PL emission properties?
- For doped CQDs, if the doping concentration is too little or too much, the luminescence intensity is usually not as strong as doping with an intermediate concentration. Why is that ?
- The PL emission spectra of CQDs in solvents with different polarities are also different. How does the solvent affect the emission spectrum of CQD?
The overlapping emission spectra of CQDs compared to SQDs typically stem from CQDs' heterogeneous sizes, diverse surface states, and varying compositions, leading to a wide range of energy levels and emissive transitions, resulting in broad, overlapping emission peaks. Narrowing down the particle size is a way to avoid the overlapping.
Thanks for providing an informative video of methodology. It makes me easier to practically understand how the process is carried on. Btw Im doing my Research Project with a Title " Synthesis Carbon Dots from Biomass(Orange Peels)"
That's great. Let me know if you have any questions.
best Demostration.
Thank you
Thank you very much for your clear explanation! This video was really really helpful :)
But i have a question, is there any difference in synthesizing carbon dots in closed drying oven(your method) or hot oil bath?
Synthesis methods and synthesis parameters can significantly influence the physicochemical, photophysical and biological properties of CDs. I’ve discussed this here: pubs.rsc.org/en/content/articlelanding/2021/nr/d1nr01389k/unauth
Big thank for this really good video, could You make a video about cristallisation with hydrothermal synthesis methods please
Thanks for your comment. Yes, sure, I am currently working on it :)
Hi this is Manju Nath Mishra
I liked you video alot❤
glad you enjoyed watching it!
Hello Sir!
This is informative and quite useful video. I request you to make a tutorial on how to measure Quantum Yield by reference method.
Thanks Pratibha for the nice comment and feedback. Sure, I am working on it.
Enjoyed the video. Looking forward to seeing future posts! I received my supply of Ascorbic Acid today and plan to create a batch of QD via Hydrothermal tonight. I've also been looking into doped-varieties of QDs.
For example, Citric Acid for the carbon source, and adding l-cysteine for the nitrogen creating N-doped QDs. According to the research paper, this combination yields a strong violet-blue reaction.
Also looked into other carbon sources like sugar that's been dehydrated by sulfuric acid. It's fun to try these different variations. However, not having such a complex lab (essentially doing this from home) i tend to only yield blue or green dots. Would love to get some red ones eventually.
thanks for your comment, Richard. Before anything please make sure you are following the safety protocol while you are making them especially if its happening in the house!
Sound like an amazing idea, there is a couple of research based on the dopant effect on the optical properties of the CDs. However, it is not very much in details and not many dopants were examined.
for the red CDs, it is very challenging to do so! as long as you find the proper dopant and optimize synthesis protocol, then you would be able to make them!
I have finally could make one after 2 years of effort haha.
anyway, good luck with your experiments and please let me know if I can be any help :)
@@NanoAustralia thank you for your reply Pooria. Today i produced my latest batch of QDs - However, mine are reflecting green rather than blue. Could it be i needed more time for particles to break down further (longer autoclave), or i somehow got some contaminate in it.
It's strange, because every method I've tried so far, and with all different types of materials, i seem to be producing green QDs. At this point i'm wondering if they're actually QDs or not - maybe something else. I know certain fluids with the same colour (in normal light) give a green reflection under UV (urine, green tea, etc). I've got in contact with my local university to see if i can hire a grad + TEM for half a day.
Another area i'm interested is the thermal conductivity/transfer of QDs. Considering it's potential as a fluid for thermal energy harvesting.
Excellent video. I would like to know what is the best grid to observe the CQDs in TEM?
If possible I would like to know what index of refraction I use for CQDs to do an analysis using DLS. I did not find these data in the literature. Thanks and congratulations for the class helped me a lot.
Thanks for your comment :). I personally use SPI Supplies® Silicon Oxide Coated TEM Grids 400 Mesh Gold Pack of 50. It's great for fluorescent materials.
In terms of IR for DLS, it depends on the solvent you've dispersed your CQDs. I use water so the RI is 1.330
@@NanoAustralia thanks! Helped me a lot. A big hug and congratulations for the class.😉👍
Thank you so much for this valuable video. I am working on synthesizing quantum dots having the best optical properties for gas sensing applications. Your suggestions would be highly important to me. Please!
Hi Dilini, Thanks for your beautiful comment! Im actually developin these NPs for biological applications. So if you can give me more information on what you are exactly expecting for your CQDs optical properties, that would be helpful.
Materials required for the Synthesis of Carbon Quantum Dots, Graphene Quantum Dots by Hydro Thermal Method( or other easy methods). Thank you sir
you can basically use any materials having C, O, and H in their structure + having a proper solvent that the starting material has good solubility in it.
@@NanoAustralia Thank you sir 🙏
Are you still active on the channel mate? I've got a few questions... As I've made about 400 batches of CDs in the last week... And for the life of me... I cannot get yellow or red 🤦♂️
@@RghnutritionAus method for red quantum dot
Please tell
فدایی داری پوریا
مخلص
Such a good video for beginners! But I have a question, you said that ions such as manganese (Mn2+) in water can change the properties of carbon quantum dots, so what properties that you referred to? Thank you. Actually I'm currently doing my research about carbon quantum dots too, and wish me luck :D
*magnesium (Mg2+)
Hi Katty, Thanks so much for your comment. The presence of any other elements besides Carbon, Oxygen, and Hydrogen can change the CQDs structure and therefore its optical properties. Addition of other elements (dopant) into the structure of CQDs causes change in graphitization degree of the core and also the surface defects distribution. It can either make a red-shift or blue-shift in absorption, excitation, and emission wavelength of your CQDs. Please let me know if you have more questions. Cheers!
عالی بود
Thanks 😊
Thank you for this video. I have a question, though, should the filter be enough to purify the CDots solution or would dialysis be a better option? Thank you
That’s a good question! If you want to further use your CDs for biological applications, you definitely need to do further purification. Like you mentioned, using dialysis bag or membrane tubes is the best option. You just need to use the correct dialysis size… have a look at this paper: pubs.rsc.org/en/content/articlelanding/2021/nr/d1nr01389k/unauth
It's an effective and good presentation for beginners like me to understand well abt the topic and experimental setup. Sir keep going. It's good.
Nithya S George thanks for your comment! Im happy it could help you understanding this content! Pleas let me know if you have any further questions
If it possible,I'm interested in knowing more abt the other synthesis methods like sputtering,Sol gel method ,green synthesis and also about the characterisation techniques ..This visual presentation is very much effective and understandable..Keep going sir.Good luck
Nithya S George such an amazing suggestions! Yeah! Actually im working on making a new video which would compare different synthesis method of CQDs and its effect on their optical properties! You can also find more information on the particle size effect on optical properties of CQD in our recent publication:
pubs.acs.org/doi/abs/10.1021/acsami.0c05217
I have also uploaded other video in my channel which is about the CQDs application in biosensing !
Sure sir. I will share the videos to my friends too.
@@NanoAustralia thanks for the article! And I really enjoyed your video.
This video is very helpful. However, can you explain for me what temperature carbon quantum dots preservation ?. Thank you !!
Thanks for your amazing comment! The temperature I used was 180 centigrade. Need to mention, the temperature is highly dependent on the ingredients you’re using (e.g. boiling temperature). Let me know if you need more information.
do we need to control the pressure? and also nice video!
Thanks, Seiya for your comment :).
Yes that can be a synthesis parameter that you can change for different synthesis. If you like to do so, you need to install a pressure gauge (you can find on eBay) on top of your reactor and monitor the pressure during the synthesis. How to change pressure? => change the filling factor. I mean every time you add different volume of solvent into the teflon => you'd get different pressure inside.
Thank you so much sir such informative video, it really helps those students who actually don't find the proper handling for synthesis.
I am doing PhD in South Korea and I want to use c dot in polymer to make water filtration membrane. But I wonder how to incorporate c dots into polymer.
thank you for your comment :). I have been using CDs incorporated with Hydrogels. While mixing them, during the polymerization, the presence of functional groups on the surface of CDs can significantly affect the polymerization. It can somehow improve the stiffness of the final hydrogel product.
Thanks for the video! How much water did you use to dilute the orange solution to yellow? Will the orange solution fluoresce under UV light without dilution?
It really depends on the amount of precursor initially used. Having said that, if the solution is too concentrated, you will receive low or no fluoresce. It is always good to have a fairly diluted solution (max 1 mg/mL), especially for UV-Vis spectroscopy. hope it is helpful.
Hi. It was so nice and helpful for me. Do you have any idea how we could purify this solution from impurities and dry them in an efficient way?
You can purify them using syringe filter, dialysis bag and centrifuge.
Best way to dry them: rotary evaporator or freeze dryer
Hie, Thanks for the informative video. do you have a document about this protocol that I can use as a reference?
Hey Obby. sure, please use my recent published paper as reference: pubs.rsc.org/en/content/articlehtml/2021/nr/d1nr01389k?casa_token=9x_YnplqCwcAAAAA:iOzcQu9Nc7Nk2K40IGKrVjL3hIWmnHJY6swTUm0cOAvrCNY22kEcc62mhRuaieGpd6mK7zmU5zYQL5Y
Very fruitful video. can you tell me the process how can we convert carbon quantum dots into solid form?
Thanks gormyour comment! Best is to either use a freeze dryer or a rotary evaporator to dry the sample. Other alternative is to add the solution of CQDs into a beaker, have a magnetic stirrer in the beaker, put the beaker on a hot plate with max temperature of 80-100C. Note, monitor this process consistently.
@@NanoAustralia Thanks
Hello sir, this video helped me a lot and i would like to know how can i make CQDs for heavy metals, i mean, is there any easy way to dope heavy metal with CQDs? Thank you
It’s just a matter of your precursor choices. Use the same method used in the video with precursors containing heavy metal in their structure.
Thank you very much sir. Your video is definitely very informative. I just want to know how to use the cdot solution for characterization under SEM (SEM analysis usually requires a powder form). How to obtain powder form of cdot?
I am unsure if you can image CDs using SEM, as a high magnification is required. I suggest using TEM and DLS for particle size measurement.
Use a rotary evaporator or freeze dryer to get CDs in powder form.
@@NanoAustralia Thank you very much
Hey I synthesized the CQDs using the same procedure, instead I used a 12micron filter paper to remove the contaminants. I am still a junior year student and I really am confused on how to characterize the sample. We do not have a TEM in our University, please guide me on how to make a sample from the liquid solution for XRD Analaysis, and UV spectrophotometer analysis. Moreover could you please let me know how should I prepare a sample from the liquid solution for the SEM analysis.
Hi Muhammad. 12um filter is relatively very large, so the contaminants and overreacted particles remain. I suggest using a 0.22 um syringe filter and then purifying further using dialysis bags with a size in the range of 1-3 kDa. You can dry the sample using a rotary evaporator or freeze dryer for XRD/SEM. UV-vis, you can use the liquid sample, but make sure to use low concentration. I don't think you can see the particles using SEM. You need to use TEM. Most DLSs cannot measure the CD's size.
After synthesis and filtration we can directly go for TEM or we need DLS as supporting information before so that my mone
y should not be wasted. I have synthesized QDs showing very good fluorescence in 365 UV lamp. . My QDs in DLS showing 300nm hydrodynamic diameter, Can I proceed for TEM. Please suggest
You don’t necessary need to do DLS before TEM. The common available DLS machines are not able to accurately measure the hydrodynamic size of CDs as they are smaller than their detection limit.
@@NanoAustralia thanks
Where do you store the prepared quantum dots? At room temp or in refrigerator?
Best to keep it at 4C. ☺️
sir how u extracted the ascorbic anhydrous from the orange juice i didnt get it as i m a beginner kindly suggest me the process
Hi, extracting AA from organic sources requires specialised knowledge and equipment. Ordering it from a chemical supplier, such as Sigma, might be easier.
Did you just used ascorbic acid?, where I can find the paper?
For this demonstration yes. But if you like to learn the CQDs synthesis in detail here is the paper: pubs.rsc.org/en/content/articlelanding/2021/nr/d1nr01389k
a mixture of ascorbic acid and arginine used as precursor. Let me know if you have difficulty with downloading the paper
Hello, thank you for kind video. Could you explain the mechanism of synthesis of CQDs? i can not understand how to fabricate it
Hi,
Would you please elaborate more on your question? Do you need more information on how to make CQDs or whats is the formation mechanism of CQDs?
@@NanoAustralia i wanna know the formation mechanism
@@user-nq1uy9je1k im gonna upload a new video on that very soon. Maybe I do it now
@@NanoAustralia really u r so kind thanks
@@user-nq1uy9je1k done, Just uploaded
How the colour of the solution from brownish at 7:06 turn in to clear yellowish colour at 7:11 ?
That's just the diluted samples in a cuvette under white light.
I observed my QDs in fluorescent microscope and SEM . It was showing large sized particles. is that are quantum dos? OR only way to observe QDs is TEM without any other preliminary observations
While it may be theoretically feasible to observe CDs through SEM, the visualization of individual CDs using basic fluorescence microscopes remains challenging. To gain a better understanding of the particle size, I recommend conducting TEM analysis. Additionally, performing XPS and FTIR experiments would be beneficial in characterizing the composition and properties of the material you have produced. Please keep me updated on your progress.
thank you
@@NanoAustralia
Did you ever work on InSb or InAs quantum dots?
unfortunately not yet.
سلام ممنونم از ویدئو مفیدتون سوالی که برام پیش اومده این هست که آیا این روش سنتز شما نیازی به دیالیز نداره؟
Hey. It really depends on the application of your CDs. If you want to use them for biological applications, I would suggest dialysis. Otherwise, syringe filter + centrifuge should be enough.
can we separate QDs from solution? like in powder form ?
you can use either a rotary evaporator or freeze dryer after the synthesis.
Thank you sir for this video. I will try this experiment producing CQDs using Hydrothermal Method and vary the temperature using organic ingredients. 😊
Thanks Mario. Sure, let me know if you have any questions.
I also recommend you to have a look at this paper
pubs.rsc.org/en/content/articlehtml/2021/nr/d1nr01389k
This paper is about the influence of synthesis parameters on the optical & biological properties of CDs.
Have you manage to produce red emmiting QD?
Yes, It is still under process. there is an issue with the stability of red emissive CQDs.
how much concentration should be used to make solutions is it ok to make 200 to 300mM solutions to increase the yield?
it really depends on the application you want to use CQDs for. For biological applications such as cell labelling, you can 100-1000 ug/mL CQDs, GENERALLY. If you mean quantum yield (QY), the CQDs' QY is independent from its concentration.
Can I use 0.22 micron membrane filter for purification ?
I would suggest use that and then use a dialysis tubing (below 30 KDa) to purify CQDs especially if you are using them for biological application. You can find more details in my recent publication: pubs.acs.org/doi/abs/10.1021/acsami.0c05217. Please let me know if you have issue getting access to this or if you need any further information.
how do you extract ascorbic acid from the fruit peels?
Hi Jasmine, sorry for late response. I probably miss your question. We have collaborators for this purpose (I have not done myself). However, fruit extracted ascorbic acid can be purchased from Sigma/Merk or other suppliers.
Sir how to make them solid, and may I know other properties like chemical surface modification and solubilities of c dots?
You can use either a freeze dryer or a rotary evaporator to make them solid.
the solubility of CDs depends on the starting material and the solvent you use for the synthesis. In most cases, you will end up having water-soluble CDs as you usually get hydroxyl and carboxyl groups on the surface of CDs.
For surce modifications have a look at the below papers. I performed two different surface modication methods:
www.sciencedirect.com/science/article/pii/S1385894721052426
pubs.acs.org/doi/full/10.1021/acsami.0c05217
Sir i am working on carbon nano dots
Please i have many questions
feel free to post your questions here. It might be the question of others too
sir we can make graphene quantum dots like this method
Yes, GQDs can be synthesised using hydrothermal method.
Sorry for asking, may I know any research paper related to this😢
You can find synthesis protocol here: pubs.rsc.org/en/content/articlehtml/2021/nr/d1nr01389k?casa_token=wD5148hJIq4AAAAA:pTqnkzDe_SQ7pNvSFIfaqs3Axy2v8grKXKAlJLXxNWmFc4CCOrrsFge7QFRahwtrDT5lz9OD2n4nToFs
Let me know if you can't access it
I can't access this review
Nice video. However, I have to point out that you need to wear safety goggles in lab.
yes!!!! that's completely right! safety first :)
What is the model of HRtem and it resolution
JEM-2100
سلام خیلی خوشحال شدم که ویدئو یه ایرانی رو دیدم در باره کربن دات ها، من دانشجو دکتری امیر کبیر هستم و دارم به تازگی کار روی کربن دات ها رو شروع میکنم . میخواستم ببینم محفظه رآکتور حداکثر چقدرش باید پر بشه و اینکه لامپ UV ای که استفاده کردی چه طول موجی بود؟ ممنون
Hi Azin, happy to have this beautiful feedback from you. The filling factor of the reactor is one of the main parameters which can directly affect the carbon dots properties (specially optical). I usually use 50 or 60% filling factor. UV Transilluminator use 320 nm excitation wavelengh. Im happy to discuss more with you regarding these dots and any further assistance, if you like! let me know :)
@@NanoAustralia Dear pooria thanks for your kind reply and the tips. I'm really interested in discussing more of our projects. I'll give you my email address, feel free to contact me. thanks
azin.rostami@gmail.com
What's the difference between carbon dot and quantum dot
Amorphous quasi-spherical nanodots which lack quantum confinement are referred to in papers as carbon nanoclusters, polymer dots or even carbon dots or C-dots; thus, “Carbon Dots” (CDs) is a more suitable name proposed in the literature. When the nanodots present quantum confinement and crystalline structure, we can distinguish between the spherical quantum dots referred to as “Carbon Quantum Dots” (CQDs) and the π-conjugated single sheet referred to as “Graphene Quantum Dots” (GQDs). Interestingly, evidence to distinguish both lies in the precursors used for their synthesis. In the case of GQDs (i.e. a disk of graphene in a size range of 2-20 nm), the precursors are mainly graphene-based materials, whereas CQDs can be prepared from other carbon nanomaterials with a crystalline structure, such as carbon nanotubes, or by pyrolysis of organic molecules subjected to high temperatures. read more here: doi.org/10.1039/C5CC07754K
@@NanoAustralia Thank you so much 🙂
Are you still active on the channel mate? I've got a few questions... As I've made about 400 batches of CDs in the last week... And for the life of me... I cannot get yellow or red 🤦♂️
400 batches?! that's a lot! Gimme more details on the following items. Synthesis method, solvent, synthetic parameter (time, temp, etc..), ingredient used for the synthesis and their molecular structure. I might be able to help you after.
@@NanoAustralia for some reason my reply isn't showing up, might have gone over the character limit 😅
Let's see if this one does
The end goal is to have something that works well with in photovoltaic applications, so trying to keep a Aquarius based solution if possible that's a similar base structure to what it would originally be if it was a due (hence the organic options)
I've filter some of my solutions with a .22 uM filter and I can't seem to get:
A. A clear solution
B. Different coloured solutions
It always ends up being green or blue...
Apparently orange or red doesn't want to work for me 😅
Part 2
Citric acid, urea and deionized water for the most, but I then started to just throw shit at the wall to see what stuck...
Which ranges from glucose and water, ascorbic acid and water, citric acid urea and red iron oxide, sweet potato, green tea leafs...
Actually part 2 😅🙄
For some reason I can't post the actual most important part of the message 🙄
Is there any publication on this video?
If yes then please send me paper name or DIO number
I want to cite it
Here are the papers:
- DOI doi.org/10.1039/D1NR01389K
- doi.org/10.1021/acsami.0c05217
hi pooriaaa
Hi hi 😂 thanks for watching this