Active release of diatomite-MgAl-layered double hydroxide nanostructures on corrosive inhibitors to effectively suppresses corrosion of LA51 alloy

Abstract

Two-dimensional (2D) materials have been potentially applicable for the corrosive resistance of alloys in corrosive media. Nevertheless, a challenge remains in adapting the 2D nanomaterial layered double hydroxide (LDH) with diatomaceous earth (DE) as two inorganic nanocontainers homogeneously combined and loaded with controlled release corrosion inhibitors. In this research, the high-efficiency anti-corrosion nanofiller for LA51 alloy protection was obtained by integrating MgAl-LDH with Sodium phosphate (SP) utilizing the unique hollow porous structure of DE as a template. As a result, the incorporation of DE-LDH-P provides a 3-order of magnitude enhancement in coating immersion in 3.5 wt% NaCl solution for 40 days compared to pure epoxy. Furthermore, two nanocontainers of DE and LDH with corrosion inhibitor loading up to 15 wt% still demonstrated excellent corrosive protection after 120 h of salt spray. The key to its protective performance is promoting controlled corrosion inhibitor release through a scientific approach that fully utilizes the slow-release properties of DE and LDH. This strategy offers a straightforward and effective approach for formulating anti-corrosion additives tailored for use in corrosive settings, with potential applications across various industrial sectors. Specifically, we advocate for the utilization of maritime instrumentation, underwater armaments, and seawater-based power sources within the domains of ship construction and marine engineering.