Replacing Oxygen Evolution with Hydrazine Oxidation at the Anode for Energy‐Saving Electrolytic Hydrogen Production

Abstract

We report the development of a cobalt phosphide nanoarray as an efficient and stable catalyst for the hydrazine oxidation reaction (HzOR) in alkaline media. Its high hydrogen evolution reaction (HER) activity enables it to be used as a bifunctional catalyst for less energy‐intensive electrolytic hydrogen generation by replacing the sluggish oxygen evolution reaction with HzOR. The corresponding two‐electrode electrolyzer using such a nanoarray as both the anode for HzOR and the cathode for HER only needs a cell voltage of 0.2 V to drive 10 mA cm−2 in 1.0 M KOH with 100 mM hydrazine, which is 1.45 V less than that for pure water splitting. This electrolyzer also shows strong long‐term electrochemical durability with nearly 100 % faradic efficiency for hydrogen evolution.

Fe3N‐Co2N Nanowires Array: A Non‐Noble‐Metal Bifunctional Catalyst Electrode for High‐Performance Glucose Oxidation and H2O2 Reduction toward Non‐Enzymatic Sensing Applications

“…As an electrochemical non‐enzymatic glucose and H 2 O 2 sensor, this nanoarray electrode shows a low detection limit and a high sensitivity with superior selectivity, specificity, and reproducibility, and its application for real sample analysis is demonstrated. This study not only provides an attractive, low‐cost, and active catalyst electrode for glucose and H 2 O 2 determination, but opens up a new avenue for designing and developing transition‐metal nitride (TMN) nanoarrays as superb catalysts for oxidation and sensing of small molecules …”

Highly Active Ternary Nickel–Iron oxide as Bifunctional Catalyst for Electrochemical Water Splitting

“…As of now the superlative materials which shows the highest activity are the noble metals like Pt, Ir, and Ru based materials but these lacks supremacy because of less abundance and more cost . Consequently, alternative catalysts which are effective in terms of cost and efficiency is required for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) . For more than decades, a range of transition metal based electrocatalysts have been synthesized which efficiently catalyze both HER and/or OER .…”

Recent Advances in Electrochemical Hydrogen Production from Water Assisted by Alternative Oxidation Reactions

“…On the one hand, as a carbon-free chemical, electrooxidation of hydrazine only releases nitrogen and water without greenhouse gas (CO 2 ) or catalyst-poisoning species (CO). [93][94][95] On the other hand, the strong reducing property of hydrazine lowers the oxidation potential, making HzOR thermodynamically more favorable than OER. [96][97][98] All of these features enable HzOR to be an alternative anodic reaction to couple with the HER for lowering the overall voltage of electrolysis.…”