Graphene–calcium carbonate coating to improve the degradation resistance and mechanical integrity of a biodegradable implant.

• Ultrathin reduced graphene oxide (RGO)-calcium carbonate (CaCO 3) coating was developed on a magnesium alloy. • RGO-CaCO 3 coating improves the corrosion resistance and mechanical integrity of a magnesium alloy. • RGO-CaCO 3 coatings introduce a new family of composite coating for temporary implants. Biodegradable implants are critical for regenerative orthopaedic procedures, but they may suffer from too fast corrosion in human-body environment. This necessitates the synthesis of a suitable coating that may improve the corrosion resistance of these implants without compromising their mechanical integrity. In this study, an AZ91 magnesium alloy, as a representative for a biodegradable Mg implant material, was modified with a thin reduced graphene oxide (RGO)-calcium carbonate (CaCO 3) composite coating. Detailed analytical and in-vitro electrochemical characterization reveals that this coating significantly improves the corrosion resistance and mechanical integrity, and thus has the potential to greatly extend the related application field. [ABSTRACT FROM AUTHOR]