Do you mean homogeneous or heterogeneous? I think starting with just Copper metal is good. If you have a carbon electrode, you could electrodeposit Cu(0) from copper salts on it too.
Kyle A. Grice Thank you for your answer professor! I meant heterogeneous. Yes, I used Cu NP 40-60nm size for testing and it working fine. I have also tested some Cu electrodeposited samples in my flow cell.