The overpotentials of water oxidation and reduction on GC electrode are very high and therefore you have a wide electrochemical window. Pt is the worst. Graphite is often contaminated with catalytically active  transition metals. In addition, graphite is rather fragile and falls apart at high potentials. The reproducible data are very difficult to obtain on graphite electrode. Nevertheless a graphite is commonly used in carbon paste electrodes

The overpotentials of water oxidation and reduction on GC electrode are very high and therefore you have a wide electrochemical window. Pt is the worst. Graphite is often contaminated with catalytically active  transition metals. In addition, graphite is rather fragile and falls apart at high potentials. The reproducible data are very difficult to obtain on graphite electrode. Nevertheless a graphite is commonly used in carbon paste electrodes

Yurii has offered some nice points. In addition, GCE is also quite cheap and is easily refreshed with the electrode surface. But for the scale-up R&D, graphite could be more practical.

Thanks for all of you for your response

But do you think if i used graphite electrode as a working electrode in the range of 0.2 to 1.5 v (Vs Ag/AgCl) will affect on the generated current at a given potential in the result cyclic voltagram??

Thanks for your cooperation

Glassy carbon electrode is cheap and may be the small overpotential required for oxidation of water on Glassy carbon electrode than platinum

I'm afraid I'm no expert on graphene... I have read enough to know that its electrochemical properties are heavily debated... It seems that the pre-treatment you do what atmosphere you keep it in prior to experiments can have a significant effect on the voltammetric behaviour you can then obtain with it. There is a lot of literature on it from authors such as Compton, Unwin, Dryfe, etc.

Dear Mosaad, please read my answer: "The overpotentials of water oxidation and reduction on GC electrode are very high and therefore you have a wide electrochemical window. Pt is the worst" Please, disprove either my or your claim.