I have synthesized GO using a modified Hummer's method as follows: 0.125 g of graphite fine powder and 0.125 g of sodium nitrate were mixed followed by the addition of 5.75 ml of concentrated sulphuric acid under constant stirring for 10 min (in an ice bath). After that, 0.775 g of potassium permanganate was added gradually to the mixture (in an ice bath) and stirred for 10 min - the mixture color turned to dark green. Then, the reaction mixture was transferred to a pre-heated oil bath and stirred at 35 °C for 1 h. The obtained mixture was diluted by the addition of 10 ml of DI water, then heated up to 90 °C for 30 min. Again 25 ml of DI water was added. Last, 1 ml H2O2 was added to terminate the reaction -the mixture turned to earthy yellow. I washed the product with distilled water and dried it at oven 60 °C for 24 h -the resulting product is a little bit sticky black solid.
You are prepared graphene not graphene oxide ,becouse graphene has abroud band aruond 25 degree,while graphite has the same band ,but has asharp peak
A sharp peak around 24-26 corresponds to stacked graphene . But if broadening is there, it means exfoliation of graphene has taken place, which is also known as reduced graphene oxide. Around 9-12 peak stands for graphene oxide. In your case you are giving high temperature ( 90 degree), avoid the temperature because it may lead to reduction of oxygen. KMnO4 is a oxidising agent. It adds oxygen groups on graphene's plane or on its edges. After oxidation, there is no need of temperature. Your rest procedure seems okay.
you are not giving enough time for stirring 10 minutes are not enough.
give at least 8 to 10 hours for stirring.
Hi..
The absence of a peak at 11 degrees in your XRD results for graphene oxide (GO) and the presence of a broad peak at around 25 degrees could be due to structural changes caused by the modified synthesis process you used.In your synthesis method, the use of strong oxidizing agents like potassium permanganate and sulfuric acid can introduce defects and oxygen-containing functional groups into the graphene layers, disrupting the regular graphene lattice. This leads to a more disordered structure, which is reflected in the XRD pattern with a broad peak at a higher angle.To obtain a sharp peak at 11 degrees, you would typically need to reduce the graphene oxide back to graphene or use a different synthesis method that maintains a more ordered structure.
Ahmed T. Mosleh Ghada Ayad Ritesh Kumar Rimjhim Yadav Thank you for your answer. Last week, I successfully got the peak at 11 degrees after I repeated the same synthesis route that I mentioned but I lowered the drying temperature to 40 °C.
I found a paper that mentioned within the range of 50-120 °C the GO can be decomposed due to decarboxylation, that's why the 40 °C works.
Why I got two peak for graphene oxide one at 11.2 degree and one at 12 degree
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