In situ formation of LDH-based nanocontainers on the surface of AZ91 magnesium alloy and detailed investigation of their crystal structure

In the presented work, the possibility of direct synthesis of LDH (layered double hydroxide) on the AZ91 surface in the presence of a chelating agent (diethylenetriaminepentaacetic acid - DTPA) is reported. Conversion layer of LDH nanocontainers were formed under ambient pressure conditions without carbonate addition in the electrolyte. The obtained LDH was characterized using experimental (SEM, XRD, TGA, XPS, Raman, etc.) and computational methods (thermodynamic calculation, modeling of possible LDH crystal structures). A comparison of three possible LDHs (LDH-OH, -NO3 and -CO3) was performed. Based on the experimental results and crystal simulation approach, it was confirmed, that the mixed LDH-OH/CO3 is grown on the surface in the presence of DTPA pentasodium salt. (C) 2021 Chongqing University. Publishing services provided by Elsevier B.V. on behalf of KeAi Communications Co. Ltd.

Automated summary

This study reports the possibility of directly synthesizing layered double hydroxide (LDH) on AZ91 surface in the presence of chelating agent DTPA. The obtained LDH was characterized using experimental and computational methods, and a comparison of three possible LDHs was performed. The results confirmed the growth of mixed LDH-OH/CO3 on the surface in the presence of DTPA pentasodium salt.