Corrosion mitigation performance of pyrazole derivative on mild steel in acidic media: Electrochemical and theoretical approach

•The inhibition effect of 5-Acetyl-2H-pyrazole-3-carboxylic acid ethyl ester (APCE) molecule on the corrosion of mild steel in HCl medium was investigated.•Adsorption of APCE molecule on the metal obeying Langmuir isotherm.•Electrochemical measurement shows the inhibition efficiency around 91%.•SEM and AFM analysis further evidenced by protective film formation.•Structure-property and inhibitor metal interaction proved by DFT approach.