Nanocatalysts for hydrogen generation from hydrazine

Abstract

Hydrogen is an key future fuel of interest because it is considered as an efficient energy carrier, like electricity, releasing only water when combining with oxygen (e.g. in a fuel cell) and therefore has no negative impact on the environment. Unfortunately we are not yet able to clear the economical and engineering hurdles to store hydrogen safely and efficiently. To overcome this, onboard hydrogen generation by hydrogen storage materials comes out to be an attractive and effective approach. Therefore, the concept of onboard hydrogen generation and use based on our requirements are gaining interest, reflected by a huge number of hydrogen storage materials with high hydrogen contents. Among them, hydrous hydrazine, which is a liquid and has a hydrogen content for hydrogen release as high as 8.0 wt%, proves to be a strong candidate for onboard hydrogen generation at ambient conditions. Nanoparticle catalysts (nanocatalysts) play a significant role to control the selective generation of hydrogen from catalytic decomposition of hydrous hydrazine. Nanocatalysts based on monometallic or two-component alloy catalysts involving noble (Ru, Rh, Pt, Pd, Ir) and non-noble metals (Fe, Co, Ni, Cu) and various non-metals have been extensively studied. Screening of a vast range of nanocatalysts thus provides a library of active and selective catalysts. The structure and activity of nanocatalysts are discussed focusing on the structure–activity relationship for selective hydrogen generation from hydrous hydrazine.