Mg-Al-Layered double hydroxide nanostructures for sustainable highly active hydrogen production via sodium borohydride methanolysis

Abstract

Developing low-cost and high-performance catalysts is essential for practical hydrogen generation from chemical hydrides. In this study, a magnesium-aluminum layered double hydroxide catalyst was successfully prepared through a urea-assisted hydrothermal co-precipitation route and applied for hydrogen production via sodium borohydride methanolysis. Structural analyses confirmed the formation of a crystalline layered framework with homogeneously dispersed nano-sized particles and a porous surface architecture. Under the selected reaction conditions (0.125 g NaBH4, 10 mL methanol, 0.01 g Mg-Al LDH catalyst, and 30 degrees C), the catalyst achieved a hydrogen generation rate (HGR) of 18,674 mL min(-)1 g(-)1 and the catalyst generated 330 mL of hydrogen within 4.5 min, indicating rapid catalytic kinetics. The enhanced activity was associated with the cooperative interaction between magnesium and aluminum active centers, which promoted surface basicity and accelerated borohydride activation. Furthermore, the catalyst preserved its structural integrity and catalytic efficiency during five consecutive reuse cycles with only minor performance loss. These findings demonstrate that magnesium-aluminum layered double hydroxide is a promising catalyst for efficient and sustainable on-demand hydrogen production in future portable clean energy conversion and storage systems.