The anticorrosion of surfactants toward L245 steel in acid corrosion solution: Experimental and theoretical calculation

•BTAH shows good synergistic inhibition effect with IQAS.•The charge transfer between the co-adsorbed inhibitor molecules was enhanced.•BTAH molecules adsorbed on metal surface through physicochemical action.•IM molecules and the inhibitor mixture (IM and BTAH) adsorbed on metal surface through chemical adsorption.