Review—Electrochemical Hydrazine Sensors Based on Graphene Supported Metal/Metal Oxide Nanomaterials

Abstract

Trace determination of hydrazine plays a key role in many agricultural as well as industrial applications. Electroanalytical techniques have become a desirable tool for tracing hydrazine levels due to their affordable cost and high performance. Several chemically modified electrodes have been devised and utilized to detect hydrazine, significantly enhancing the electron transfer rate and lower detection limits. Recently, the exceptional features of nanomaterials assembled of graphene–metal/metal oxide nanoparticles have been exploited to provide new strategies for highly sensitive and selective hydrazine sensors. Here we focus on the most recently developed nanostructured metal/metal oxide nanoparticles assembled with graphene (such as palladium, gold, bismuth, iron oxide, zinc oxide, cobalt oxide, and manganese dioxide) for hydrazine detection using electrochemical modality. In addition, the sensing mechanism, electrocatalytic oxidation, and the effect of pH values on the electrocatalytic activity of hydrazine at the surface of graphene–metal/metal oxide modified electrodes were also extensively reviewed.