Highly efficient metal-free ethylenediamine-functionalized fullerene (EDA@C) electrocatalytic system for enhanced hydrogen generation from hydrazine hydrate

A synthesized non-precious metal-free electrocatalyst is demonstrated using the hydrazine hydrate oxidation reaction as a model reaction of hydrogen production. The C 60 nanocomposite functionalized with ethylenediamine (EDA@C 60 ) was fabricated using a simple chemical approach. The EDA@C 60 composites were characterized using field emission scanning electron microscopy, energy dispersive analysis of X-rays, Fourier-transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, and electrochemical techniques. In this study, the nitrogen lone pairs from the ethylenediamine surface-functionalized on C 60 are responsible for the further enhancement of electrocatalytic activity towards the hydrazine oxidation reaction. Comparative electrochemical studies with acid-treated C 60 , i.e. , O-C 60 , and the further-functionalized ethylenediamine catalysts (EDA@C 60 ) demonstrated high performance, which was ascribed to their inferior onset potential and better stability. The electrochemical measurements indicate that the EDA@C 60 composites demonstrate twice the current density (20 mA cm −2 ) and a better onset potential (0.2 V vs. SCE) than O-C 60 for hydrazine oxidation. The electrocatalytic hydrogen evolution reaction (HER) performance of the O-C 60 and EDA@C 60 electrocatalysts indicate onset potentials of 0.37 V vs. SCE and 0.20 V vs. SCE, respectively. The experimental and analytical studies found that the nanocomposites with ethylenediamine, i.e. , EDA@C 60 , not only extend the surface area compared to that of O-C 60 , but also promote the self-decomposition of hydrazine molecules. Ethylenediamine functionalized C 60 (EDA@C 60 ) based electrocatalyst demonstrated for hydrazine oxidation and it shows more than double current density i.e . 20 mA cm −2 at an ultralow onset potential of 0.2 V vs . SCE with better stability over oxidized C 60 .