The existence of Hydrogen sulfide (H2S) during the petroleum production and its high risks is the main reason to develop a smart, cheap and flexible device for H2S monitoring. This article is focusing on developing electrochemical sensors, which seems to have a promising potential. Polypyrrole (Ppy) and its two composites were prepared; Ppy doped with Cupper oxide (CuO) nanoparticles (Ppy/CuO) and...