Electrooxidation of Hydrazine Utilizing High-Entropy Alloys: Assisting the Oxygen Evolution Reaction at the Thermodynamic Voltage

Citations Over TimeTop 10% of 2021 papers

Abstract

Hydrazine electrooxidation is an important reaction as it assists in decreasing the OER overvoltage. Herein, we report the utilization of a high-entropy nanocatalyst alloy for the electrooxidation of hydrazine. The high-entropy nanocatalyst comprising five elements (Ag, Au, Pt, Pd, Cu) shows profound activity toward this molecule at a low overvoltage. An intriguingly high-entropy nanocatalyst prepared by the casting-cum-cryomilling method is endowed with the unique catalytic activity for the HzOR. A detailed analysis of gaseous product points to the formation of nitrogen as well as oxygen as the oxidation product, a sign of accompanying the oxygen evolution reaction (OER). Interestingly, a significant amount of oxygen is detected at 1.13 V (reversible hydrogen electrode (RHE)) in a neutral buffered medium, confirming that the OER is functional at a voltage near the thermodynamic voltage of 1.23 V (RHE). The quantitative contribution of each hydrazine and OER is ascertained, which explains a vital insight into this reaction. Density functional theory calculations showed that both HzOR and OER assist each other where the electron-donating effect of H2O to the surface can reduce the endothermicity of the HzOR. However, the electron acceptance of *NHNH2 helps in a favorable overlap of the HEA Fermi level and vacant states with the HOMO of H2O.

Related Papers

• → Catalytic Decomposition of Hydrazine and Hydrazine Derivatives to Produce Hydrogen-Containing Gas Mixtures: A Review(2022)21 cited
• → Pyrimidine reactions. Part XVIII. The conversion of 4-methoxy-5-nitropyrimidine into 3-amino-4-nitropyrazole by hydrazine(1968)18 cited
• → Studies on Hydrazine: The Heat of Formation of Hydrazine and of Hydrazine Hydrate(1939)11 cited
• → Determination of Hydrazine in Pharmaceuticals IV: Hydrazine and Benzylhydrazine in lsocarboxazid(1985)8 cited
• Gelation of Hydrazine Nitrate-hydrazine Hydrate Double Components(2005)