Study on synergistic hydrogen generation from aluminum-based composites in different forms of water

Abstract

The environmental suitability of hydrogen storage materials is significantly influenced by the way aluminum reacts synchronously with water, ice, and water steam. The straightforward ball milling process was used to synthesize Al-based composite materials with carbon nanotubes (CNTs) or graphene oxide (GO). The reactivity of the composites in various types of water was investigated. The Al/Bi/CNT and Al/Bi/GO composites may react in liquid water, low-temperature ice, and high-temperature steam. The hydrolysis promotion of Al-based composites by CNTs is superior to that of GO, whether in liquid water at 20 °C or ice at −20 °C. The maximum hydrogen generation rate of Al/Bi/CNT composites can reach 34.6 mL g⁻¹ s⁻¹ at 20 °C. The hydrogen generation volume of Al/Bi/CNT can reach 700 mL g⁻¹ in 15 min on ice at −20 °C. Moreover, the ignition temperature and ignition delay time of Al/Bi/CNT are shorter than those of Al/Bi/GO in high-temperature steam. The hydrogen generation volume from Al/Bi/CNT at 200 °C can reach 853 mL g⁻¹. These may originate from the unique one-dimensional nanostructure of CNTs, which provides more surface area or reaction sites during the hydrolysis of the composite.