Novel highly active electrocatalysts for hydrazine hydrate fuel cell application were developed, synthesized and integrated into an operation vehicle prototype. The materials show in both rotating disc electrode (RDE) and membrane electrode assembly (MEA) tests the world highest activity with peak current density of 16,000 A g(-1) (RDE) and 450 mW cm(-2) operated in air (MEA).

Novel highly active electrocatalysts for hydrazine hydrate fuel cell application were developed, synthesized and integrated into an operation vehicle prototype. The materials show in both rotating disc electrode (RDE) and membrane electrode assembly (MEA) tests the world highest activity with peak current density of 16 000 A g À1 (RDE) and 450 mW cm À2 operated in air (MEA).The automotive world will be changed in 2015, when leading manufacturers will publicly introduce their first generation of commercial fuel cell vehicles. It should be noticed, however, that these automobiles were developed with proton exchange membrane (PEM) technology and membrane electrode assemblies (MEAs) in fuel stacks containing platinum catalysts for both hydrogen oxidation and oxygen reduction.There are several drawbacks of PEM-based technology, including: the high cost of fuel cell membranes, the extremely high cost of platinum, and the absence of a developed hydrogen infrastructure. Further, the use of hydrogen requires a high-pressure tank, which requires a full redesign of the automobile frame. These factors result in a high-cost commercial vehicle with a low driving range and safety issues.In contrast to PEM hydrogen fueled vehicles development, researchers from Daihatsu Motor Co. have introduced the idea of anion-exchange membrane fuel cell with liquid fuels. [1][2][3][4][5][6][7][8][9][10][11] Switching from acidic proton exchange to alkaline, anion-exchange membranes has many benefits, including: 1) fast fuel oxidation and oxygen reduction and 2) possible use of cheaper non-platinum group metal catalysts as anode and cathode material for both sides of the MEA. The liquid fuel of choice was hydrazine hydrate, which has no carbon atoms and thus will not contribute to increased CO 2 levels, the theoretical electromotive force is 1.56 Vand it can be oxidized by number of cheap catalysts. [12] To meet the power output requirements of a stack with limited size, the anode material should provide the highest power density, be stable, and selective toward the production of water and nitrogen with no ammonia (NH 3 ) generation. Up to now, catalysts reported had a low activity with operation in air (real vehicles operation conditions).Herein we report the synthesis of novel Ni-based supported catalysts by a completely solvent-free method. The method is based on a mechanochemical approach and is scalable to hundreds of kilograms of catalyst and can be considered a "green" synthesis method compared with conventional synthesis, which requires the use of solvents. These catalysts show high activity in both rotating disc electrode (RDE) and MEA tests, with real vehicles operation conditions. The effects of catalysts loading and carbon addition on hydrazine electrooxidation were studied on nickel-based materials for the first time.These electrocatalysts for hydrazine electrooxidation were synthesized by solvent-free impregnation of nickel and zinc precursors by using a high-energy mechanochemical approach. The synthesized materials were compreh...

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Alkaline or hydroxide exchange membrane water electrolysis (HEMWE) is a promising technology for green hydrogen production using platinum group metal-free catalysts and stainless steel, an advantage of alkaline water electrolysis (AWE), and a gas impermeable membrane, a parallel to proton exchange membrane electrolysis (PEMWE). However, the HEMWE requires supporting electrolytes and there is minimal understanding of their role on the respective reactions. Without SELs, HEMWE performance and durability is worse than PEMWE systems. Herein, consistently feeding potassium hydroxide anolyte, we systematically study the effects of catholyte SELs in HEMWEs including dry vs wet operation, cation effects, anion effects, and cation/OH ratios on cell potential and stability. We report that (i) hydration of the cathode improves high current density operation by preventing dehydration of the hydroxide exchange membrane (HEM), (ii) there was no correlation between cation type and cell potential, (iii) cell potential and high frequency resistance did not correlate with SEL conductivity, (iv) cathodic carbonate SEL had a significant negative effect on cell performance, (v) increased cation/OH ratio also caused increased cell potentials. Overall, this study concludes that feeding water or potassium hydroxide solution is desirable to improve the AEMWE performance.

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