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I am trying to make graphene oxide but failing miserably. The XRD peak is at 24 (2θ) instead of being near 10. Raman shows correct g and d peaks but are not very sharp. The colour of the end product is not yellow but grayish.

I have followed all the steps of Tour's and Hummers's methods.

But I am confused about should I add Graphite powder/flakes to $\ce{H2SO4}$ or $\ce{H2SO4}$ to the powder. And when should I add NaNO3 and how?

What I have tried is adding the $\ce{NaNO3}$ and graphite powder and mixing them and then added this mixture to the $\ce{H2SO4}$ and followed the rest of the process. Dried it at 60°C for over two days.

Also it will be helpful to know if the stirring rpm matters.

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    $\begingroup$ There have been dozens of other papers on the subject of refining Hummers´ method. Read more! ;) And make sure you wash the end product free of alkali before drying, especially if you want to produce larger amounts!! $\endgroup$ – Karl May 20 '20 at 7:04
  • $\begingroup$ @Karl I used HCl and ethanol for the washing process. Should have mentioned it (^--^) (Forgot!!)..About the papers, I have gone through a few of them and they all usually use an oxidizing agent like K2FeSO4 instead of NaNO3 or even pre-oxidized graphite. Still I am curious about the Tour's and Hummers's method. There was a correction to Tour's method about the order of adding chemicals. So I wanted to know if I am doing something wrong in the order of adding the chemicals. So far I could not get my hands on a paper that dealt with it. Any advice please... Does it affect the final product? $\endgroup$ – New learner May 20 '20 at 7:36
  • $\begingroup$ 10.1021/acsnano.8b00128 This is the correction paper. But it did not discuss the effects of the order of other chemicals. $\endgroup$ – New learner May 20 '20 at 7:39
  • $\begingroup$ There shoud be a number of papers from Tölle and Mülhaupt, early 2010s. $\endgroup$ – Karl May 20 '20 at 8:08

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