Synthesis of NaBH4 as a hydrogen carrier from hydrated borax using a Mg–Al alloy

In this work, we reported an energy-saving and cost-efficient process for the (re)generation of NaBH4 by ball milling hydrated borax (Na2B4O7·10H2O) with a Mg–Al alloy under ambient conditions. The introduction of abundant and readily available Al can increase air stability of the reducing agent. A high yield up to 85.2% could be achieved by using Mg17Al12 because of its hardness and brittleness.