Direct synthesis of MgH2 nanofibers from waste Mg

In this paper, we present a new route for recycling waste Mg with the production of MgH2 nanofiber, which is a promising candidate for energy storage and conversion used in Li-ion batteries and H2 storing technologies. Highly pure MgH2 nanofibers were successfully manufactured from Mg-alloy swarfs (AM60B and AZ91D) via the hydriding chemical vapor deposition (HCVD) process. The possibility of recycling all types of Mg scraps using the HCVD process was demonstrated, which requires only a pretreatment of obtaining a dried raw material. The HCVD method shows many advantages over other methods in the synthesis of MgH2: it can produce MgH2 at low cost using waste Mg as the raw material, requires less energy, offers a high-purity product, and enables control over the growth of nanosized structures.

► Highly pure MgH2 nanofibers were prepared from waste Mg using a HCVD process.
► The HCVD process enables control over the growth of nanosized-MgH2 directly.
► The new process can produce MgH2 at a low-cost using waste Mg as raw material, which shows the possibility to recycle all types of Mg scraps.
► The as-prepared nanofibers are expected with excellent performance for use in H2 storage and Li-ion batteries.