Hydrazine Energy Storage: Displacing N₂H₄ from the Metal Coordination Sphere

Abstract

Hydrogen carriers, such as hydrazine (N2H4), may facilitate long duration energy storage, a vital component for resilient grids by enabling more renewable energy generation. Lanthanide coordination chemistry with N2H4 as well as efforts to displace N2H4 from the metal coordination sphere to develop an efficient catalytic production cycle were detailed. Modeling the equilibrium of different ligand coordination, it was predicted that strong sigma donor molecules would be required to displace N2H4. Monitoring competition experiments with nuclear magnetic resonance confirmed that trimethyl phosphine oxide, dimethylformamide, and dimethyl sulfoxide displaced N2H4 in large or small lanthanide complexes.

Ultrawide Hydrazine Concentration Monitoring Sensor Comprising Ir−Ni Nanoparticles Decorated with Multi‐Walled Carbon Nanotubes in On‐Site Alkaline Fuel Cell Operation

“…Hydrazine (N 2 H 4 ) is a flammable, toxic, colorless, basic, and water‐soluble molecule that has been widely used as a reducing agent in synthesis, intermediates for pharmaceuticals, insecticides, explosives, and as oxygen scavengers in water boilers [1–3] . Nowadays, hydrazine is increasingly exploited as an energy source in fuel cells, and in particular in alkaline fuel cells, owing to its high hydrogen content and environmentally‐friendly oxidation by‐products, mainly in the alkaline environment [4–6] . For example, hydrazine fuel cells (HzFCs) offer the advantages of low theoretical potentials (−0.33 V vs. RHE, reversible hydrogen electrode) and the possibility of using cost‐effective transition group metals as electrode materials, thereby minimizing the dependence on the costly and scarce platinum group metals [7–10] .…”

“…[1][2][3] Nowadays, hydrazine is increasingly exploited as an energy source in fuel cells, and in particular in alkaline fuel cells, owing to its high hydrogen content and environmentally-friendly oxidation by-products, mainly in the alkaline environment. [4][5][6] For example, hydrazine fuel cells (HzFCs) offer the advantages of low theoretical potentials (À 0.33 V vs. RHE, reversible hydro-gen electrode) and the possibility of using cost-effective transition group metals as electrode materials, thereby minimizing the dependence on the costly and scarce platinum group metals. [7][8][9][10] To fabricate commercially viable HzFCs, it is critical to monitor the residual concentration of hydrazine in the fuel tank on-site and use it as a criterion for adjusting fuel recycling and minimizing the introduction of toxic and mutagenic hydrazine into ecosystems.…”