Penetration into the inhibition performance of two piperazine derivatives as high-efficiency inhibitors for copper in sulfuric acid environment

•High efficiency CBP and BP molecule were discovered to retard the copper corrosion.•Molecular dynamics simulations show that CBP is more parallel to copper surface.•The inhibition efficiency of 5 mM CBP and BP for Cu in H2SO4 was more than 95%.•The presence of halogen Cl enhances the anti-corrosion efficiency of CBP.