New pyrazole compounds as a corrosion inhibitor of stainless steel in 2.0 M H2SO4 medium: Electrochemical and theoretical insights

•Py-1 and Py-2 act as effective inhibitors for stainless steel in acidic solution and their effectiveness increases with their concentration.•Polarization results showed that all compounds displayed anodic-type behavior. Inhibition efficiencies of Py-1 and Py-2 followed the order: 90.9% (Py-2) < 96.7% (Py-1).•Adsorption of both studied pyrazole obeys Langmuir adsorption isotherm.•Adsorption of the examined compounds on metallic surface was reinforced with SEM-EDAX studies.•DFT results suggested that Py-1 and Py-2 molecules have strong ability to transfer their electrons into d-orbitals of surface metallic atoms.