Zirconium ions integrated in 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) as a metalorganic-like complex coating on biodegradable magnesium for corrosion control

In this study, a coating of ionic Zr integrated in 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) metalorganic-like complexes was applied on Mg for corrosion control. HEDP was first immobilized on alkaline pretreated Mg followed by an alternating dip-coating process of Zr ions and HEDP to build a complex coating on Mg. This coating was demonstrated to be homogeneous, compact and with a metalorganic-like framework firmly anchored on Mg. This coating led to reduced corrosion current densities and remarkably suppressed long-term in vitro degradation of Mg in phosphate buffer saline (PBS). This complex coating showed promise for surface modification of Mg in biodegradable applications.