Supra Hydrolytic Catalysis of Ni3Fe/rGO for Hydrogen Generation

Abstract

Abstract Light metal hydrolysis for hydrogen supply is well suited for portable hydrogen fuel cells. The addition of catalysts can substantially aid Mg hydrolysis. However, there is a lack of clear catalytic mechanism to guide the design of efficient catalysts. In this work, the essential role of nanosized catalyst (Ni3Fe/rGO) in activating micro‐sized Mg with ultra‐rapid hydrolysis process is investigated for the first time. Here, an unprecedented content of 0.2 wt% Ni3Fe/rGO added Mg can release 812.4 mL g−1 hydrogen in just 60 s at 30 °C. Notably, an impressive performance with a hydrogen yield of 826.4 mL g−1 at 0 °C in only 30 s is achieved by the Mg‐2 wt% Ni3Fe/rGO, extending the temperature range for practical applications of hydrolysis. Moreover, the four catalysts (Ni3Fe/rGO, Ni3Fe, Ni/rGO, Fe/rGO) are designed to reveal the influence of composition, particle size, and dispersion on catalytic behavior. Theoretical studies corroborate that the addition of Ni3Fe/rGO accelerates the electron transfer and coupling processes and further provides a lower energy barrier diffusion path for hydrogen. Thus, a mechanism concerning the catalyst as migration relay is proposed. This work offers guidelines designing high‐performance catalysts especially for activating the hydrolysis of micro‐sized light weight metals.

Keywords

• catalyst
• hydrogen generation
• Mg hydrolysis
• migration relay