A novel nanoporous Mg-Li material for efficient hydrogen generation

Abstract

• Nanoporous Mg-Li material is successfully prepared for the first time. • This material can deliver 962 ml g −1 H 2 in 15 min at 0 °C and in 3 min at 50 °C. • The advances come from the nanoporous structure and the addition of li element. • The growth mechanism of the nanoporous Mg-Li material is proposed. Hydrogen generation material is a new kind of energy material that can supply hydrogen by reacting with water and is drawing more and more attention with the development of hydrogen economy. In this study, a novel nanoporous magnesium-lithium material prepared by a physical vapor deposition method exhibits an excellent hydrogen generation property. It generates hydrogen efficiently and quickly with saltwater, reaching a hydrogen generation amount of 962 mL g −1 and hydrogen generation rates of 60 mL g −1 min −1 , 109 mL g −1 min −1 , 256 mL g −1 min −1 and 367 mL g −1 min −1 at 0 °C, 25 °C, 35 °C and 50 °C, respectively. The nanoporous magnesium-lithium material is composed of a solid solution phase with a magnesium-lithium atomic ratio of 17:3. By synchrotron radiation analysis, the sizes of the nanopores are in the range of 100 nm ∼ 600 nm with an average size of 280 nm, and the porosity is calculated to be ∼42.4%. The improved hydrogen generation property is attributed to the nanoporous structure with a high specific surface area, and the addition of lithium element which acts as active sites in hydrogen generation process.