“…A wide range of coatings on Mg and Mg alloys have been developed to increase the corrosion resistance, such as conversion coatings (micro arc oxidation (MAO) surface [9][10][11][12] , plasma ion implantation surface [13] , chemical conversion surface [14][15][16][17][18][19] , hydrothermal conversion technique [20] etc. ), deposited coatings (calcium phosphate coating [21][22][23] , TiO 2 coating [24,25] , polymer coating [26,27] etc.)…”