The Raman spectra of TiO2/Graphene nanocomposite show the RGO with D band located at about 1340 cm-1 and G band at about1581 cm-1. G band shows the in plane vibration of sp2 bonded carbon atoms, the D band was the presence of sp3 bond and other sp3 defects in graphene. The 2D band at around 2780 cm-1.
I know the positions of the bands and the reasons very well..Sir but i have asked Why these bands are not there..What will be the possible reasons for that?
Tio2/Graphene nanocomposites were made by direct mixing in mortar pastle (grinding) 2 hours using distl.water and then the paste was coated by doctor blade method on ITO. these films are then annealed in furnanace at 450C for 1/2 hr.
To make sure there are no effects of graphene amount, grinding, and annealing (of course graphene is stable under the applied temperature) I would repeat the same experiments without TiO2 as well as without grinding (TiO2/Graphene) using the doctor blade and ITO. Then, I would try using the same Raman measurement conditions for all 3 samples after adjusting Si peak.
We have checked several references, but in all G and D bands should be present. Basically carbon based materials can with stand more than 450C. So may be the mixing ratio is quite low for graphene than TiO2, which leading to disturb the carbon structure of graphene. So we suggest to repeat the experiments by changing/increasing the graphene Wt%. In addition, we suggest please use mineral oil instead DD water to make Graphene/TiO2 paste by using doctor blade method. Please suggest to take as reference of our group's paper in solar cells for making carbon paste by doctor blade method. Thanks.
Thanks Sir for the paper. Which mineral oil you have used? And how to seal the DSSC while taking I-V characteristics? Can we use scotch tape for this? IS area illuminated can affects the efficiency?