Hydrogen storage properties of MgH2 + Mg2NiH4–Co/C ternary nanocomposite

The application of ternary nanocomposite synergetic catalysis has proven to be an effective modification strategy for enhancing MgH2 hydrogen storage performance. The ternary magnesium-based hydrogen storage alloy, composed of MgH2+Mg2NiH4–Co/C, is successfully prepared and characterized. Through the optimized preparation process and the optimal ratio, it is observed that the catalyst Mg2NiH4–Co/C significantly reduces the reaction activation energy, resulting in a the initial hydrogen desorption temperature is approximately 60 °C lower than that of pure MgH2. The enhanced hydrogen storage properties are attributed to the synergistic catalytic effect of carbon (C) combined with the formation of Mg2Ni and Mg2Co facilitated by Ni and Co elements. Furthermore, the reversible phase transitions of Mg2Co/Mg2CoH5 and Mg2Ni/Mg2NiH4 serve as "hydrogen pumps" further aiding in hydrogen storage. This study extends the investigation of the synergistic catalytic effect of ternary nanocomposites to enhance the hydrogen storage performance of alloys.