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Aluminum (Al) and lithium borohydride (LiBH 4 , LB for short) are highly promising candidates for chemical hydrogen storage. However, the direct utilization of Al–H 2 O reaction faces significant challenges due to the inherent issue of surface passivation, which prevents the ongoing reaction between Al and H 2 O. Additionally, the hydrolysis of LB is constrained to temperatures exceeding 0 °C, and the development of cost-effective catalysts that enable efficient hydrogen release from LB hydrolysis remains a bottleneck in realizing its practical application. Herein, we present an efficient noncatalytic hydrogen generation system utilizing Al and LB mixtures, enabling H 2 production over a broad temperature range using methanol, ethanol, or their mixtures as reaction solvents. Our results demonstrate that the H 2 generation kinetics of Al-LB composites can be precisely tailored by adjusting various parameters, such as LB content, ball-milling time, reaction temperature, and solution composition. In comparison with the traditional Al and its alloy systems, Al-LB composites exhibit remarkable performance in both hydrogen capacity and H 2 kinetics. For instance, the Al-50 % LB composite achieves a hydrogen yield of 2322 mL g−1 H 2 within 5 min (∼80 % fuel conversion). Specifically, with a 70 % LB content, the composite generates over 3100 mL g−1 H 2 within the same time, realizing nearly 90 % fuel conversion. Notably, the apparent activation energy of the Al-30 % LB and Al-50 % LB composites is determined to be 29.1 kJ mol−1 and 13.9 kJ mol−1, much lower than that of Al-based hydrolyzable materials. These findings hold significant importance for the advancement of practical Al-based hydrogen generation systems designed for mobile or portable applications. • An efficient H 2 generation system employing Al-LB mixtures is developed. • The Al-70 % LB composite releases >3100 mL g−1 H 2 in 5 min with ∼90 % fuel yield. • The apparent activation energy of the Al-50 % LB composites is 13.9 kJ mol−1. • The Al-50 % LB composite shows considerable H 2 production even at 263 K. [ABSTRACT FROM AUTHOR]

Currently, economic hydrogen production is the key issue preventing the application of the hydrogen as the energy carrier for global low-carbon and ever-increasing energy challenges. Hydrogen generation by spontaneous hydrolysis reaction of light metal-based materials including Mg, Al and NaBH 4 , is a promising method integrating safe storage and effective supply of hydrogen. However, these hydrolytic materials are still plagued by sluggish hydrogen kinetics and low H 2 yield, owing to the formation of the surface passivation layers. While numerous strategies such as refining material's structure, compositing with other materials, alloying and modifying aqueous solutions, have been proposed to enhance hydrogen generation performance, the high cost caused by irreversibility hinders the large-scale application. Therefore, low cost regeneration of materials from hydrolytic byproduct is essential for hydrogen generation via hydrolysis. Herein, this review presents the recent research progress on above topics as well as their application in fuel cells. The future challenges and opportunities in this area are also described. [Display omitted] • A overview in hydrogen generation from the hydrolysis of light metal-based materials is introduced systematically. • The effective regeneration technologies of light metal-based materials from their hydrolytic byproducts are delivered in detail. • The application of hydrolytic hydrogen production systems in fuel cells is discussed briefly. • The challenges and opportunities associated with hydrogen generation from light metal-based materials are described. [ABSTRACT FROM AUTHOR]