Abstract: In one aspect, the present invention provides a method of protecting a metal vessel susceptible to corrosion by hydrogen sulfide, the method comprising: (a) applying a coating composition comprising a metal oxide precursor material, a solid metal oxide, and a solvent to a surface of the metal vessel to be protected; (b) converting at least a portion of the metal oxide precursor material to a metal oxide, and removing at least a portion of the solvent to provide a metal oxide layer disposed on the surface of the metal vessel; and (c) converting at least a portion of the metal oxide layer to a corresponding metal sulfide layer or a metal oxysulfide layer.