Synthesis of a Nanosized Carbon-Supported Ni Composite and Its Remarkable Catalysis for Hydrogen Desorption from the LiBH4–2LiNH2 System

A nanosized Ni@C composite (Ni particles: < 10 nm) was successfully synthesized by casting a Ni-based metal–organic framework MOF-74(Ni) filled with furfuryl alcohol at 700 °C. The resulting Ni@C composite exhibits remarkable catalytic activity for reducing the operating temperature of hydrogen release from the LiBH4–2LiNH2 system. The LiBH4–2LiNH2–10 wt % Ni@C sample releases approximately 10 wt % of hydrogen at 135–250 °C, and the end temperature for hydrogen release is reduced by 110 °C in comparison to that of the pristine sample. During dehydrogenation, nanosized Ni remains almost unchanged and only works as a catalyst to reduce kinetic barriers of hydrogen release from the LiBH4–2LiNH2 system, which is responsible for lowered dehydrogenation temperatures of the Ni@C-containing sample. More importantly, the dehydrogenated Ni@C-containing sample presents a loose porous morphology that slightly improves its rehydrogenation properties.