Dust cloud explosion characteristics and mechanisms in MgH 2 ‐based hydrogen storage materials

The mechanisms involved in premixed magnesium and hydrogen hybrid and synthetic MgH 2 dust cloud explosions were investigated. The results revealed that trace amounts of H 2 in Mg explosions can markedly increase explosion severity. Furthermore, H 2 addition can weaken the influence of oxygen deficiency on Mg explosion. Moreover, the explosion intensity of synthetic MgH 2 was far stronger than that of premixed Mg/H 2 mixture or Mg alone because the vacancy defects in Mg and H atoms can form after dehydrogenation of MgH 2 , which caused that Mg and H 2 are prone to oxidation and nitrification in air atmosphere at a low temperature, thereby promoting the explosion. This demonstrates that the explosion risk of MgH 2 (even other H 2 storage materials) is related to its H 2 storage capacity and dehydrogenation temperature. Therefore, for H 2 storage materials, the better H 2 storage performances can exhibit higher explosion risks.