2-Mercaptobenzothiazole doped chitosan/11-alkanethiolate acid composite coating: Dual function for copper protection

► A new composite coating with anticorrosion and antibacterial properties has been fabricated with a facile method. ► High protective efficiency was achieved with much less inhibitors. ► The prepared composite coating can provide protection in both aerated and hydrogen sulphide-containing sodium chloride solution. ► Even the dissolved chitosan macromolecule is still bactericidal active against sulphate reducing bacteria.