Graphene-based Nanomaterials for Electrochemical Sensing of Hydrazine: A Short Review

Background: Hydrazine is a well-known hepatotoxic, mutagen, and carcinogen. It adversely affects not only the liver, DNA, and kidney but the central nervous system also. As per the record of the Environmental Protection Agency (EPA), the United States, the optimum concentration of it has been permitted in sewage and industrial and agricultural effluents is 0.1 ppm. Therefore, monitoring hydrazine concentration is essential at the trace level. This review focuses on the preparation, characterization, and application of graphene-based nanomaterials for the development of electrochemical sensors for hydrazine sensing. Methods: Several literature reports over the last decade, i.e., 2010 to 2021, have been tried to summarize the development of different electrochemical sensors using graphene-based nanomaterials for the detection of hydrazine in water and other environmental samples. The performance of several reported modified electrodes has been reviewed in terms of limit of detection, linear range, selectivity, etc. Results: Graphene-based nanomaterials/nanocomposites offer a new path toward the development of high-performance electrochemical sensors due to their greater active surface area and good electron transference property. Furthermore, these nanostructures have defects in edges, and they can be expected to show more reactivity towards chemical species compared to pristine graphene. However, these novel graphene nanostructures have been scantily explored in the development of electrochemical sensors. Conclusion: The review presents that graphene-based nanomaterials offer excellent electrocatalytic and electrochemical behavior toward hydrazine detection. The performance of fabricated electrochemical sensors has been compared in terms of linear range, limit of detection, stability, and sensitivity. Still, no commercialized electrochemical sensor is available and there is enough scope to synthesize an efficient graphene-based nanomaterial to develop a portable and on-site electrochemical sensor for hydrazine detection.