My problem is that I couldn't find the good temperature for reduction. It shows in XRD that we have additional peaks.
Dear Zahra Gohari
Graphene can be synthesized by different types of method. Without knowing the synthesis method , it is difficult to solve your problem.
Dear Karthikeyan Krishnamoorthy
Thank you for your answer
I used Staudenmaier method. I put my samples at 1050 C for 30 sec. I had one peak in XRD(it was OK). I changed it to Hummer method. for reduction, i test T and t like previous step but XRD showed that it was not enough for complete reduction than I put samples at 1000 c for 3 min but i have additional peaks in XRD. should I extend them to 10 min? or use chemical reduction?
Thanks again
You can increase the time for while. And also compare with the XRD of GO synthesized by Hummer's method since there is possibility for impurities (metal ions) in that.
it is not impurity. in XRD of GO we have one peak for (001).
Dear Zahra Gohari,
Generally graphene can be grown by chemical vapor deposition. In general in CVD, the copper as a substrate , it can act as a catalyst for the reaction,Hydrogen is used as reduction gas and methane is the carbon source, normally temparature can be 950 to 1000 C is the better conditions.
when you reduce the GO then why using such a high temperature, It will reduce again the functionalitieas on the surface of graphene sheet. Checked your reduced sample after drying at 100 degree compare your result with samples treated at high temperature. You will find the shift in the peak towards lower angle. For attachment of TiO2 on the surface of graphene sheet you can use EG, aqueous solution , Hydrazine depends on synthesis method.
Dear Kefayat ullah
I use thermal reduction. I should put GO at 1000 because at the end I need pure graphene without any functional groups. if I don't increase Temperature to 1000 how can I obtain graphene?
I read your articles about Pt/graphene-TiO2, you used GO (before microwave) not graphene but I want graphene.
I have another question about microwave:
I couldn't find suitable vessel for microwave. I test different ones but all of them broke for spark. do you use especial one?
Ok pure graphene is OK at this temperature. But for attachemnt u need graphene oxide and during the reaction time attachemnt of nanoparticles and reduction to graphene will be observed. Using some media,,,
No special vessel needed you need to control the temperaure. means you have to irradiate your sample with microwave for short interval of time,.,,
for example instead of 10 s, I should do it at two 5 s separately. before starting spark I should turn it off and start again. yes?
Yes try to irradiate first for 5S and then off the Oven for 5 S, trry out this for 300 sec,,,,,,also try your sample with different small time interval and fixed the irradaition time for your sample,,,
Dear Kefayat ullah
Thanks again for your answer
why you didn't use water instead of EG? Is it for microwave effect ( because EG is a better microwave absorber) or for your precursor?
Its because of EG is good absorber and hence provide maximum time for interaction as compare to water molecule.
Dear Kefayat ullah
for hydrothermal and sol -gel we need to solve salts in solution. TiO2 is insoluble in water. why did you write(in new article) TiO2 can grow on graphene sheets?
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