SELENIUM MODIFIED PENCIL GRAPHITE ELECTRODE FOR EFFICIENT HYDRAZINE SENSING IN WATER

Abstract

Hydrazine, a routine chemical in various industries, is regarded as a toxic chemical even in trace amounts as it poses a serious threat to human beings owing to its carcinogenic and mutagenic nature. Therefore, it is crucial to detect its presence in aqueous media. Herein, we reported modifying a pencil graphite electrode with Se nanostructures (Se / PGE) by a facile chemical bath deposition (CBD) method for the first time. The Se / PGE exhibited outstanding, reproducible, and selective electrocatalytic activity for hydrazine determination. Modifying PGE with Se nanostructures significantly improved the electrochemical active surface area and electron transfer kinetics for hydrazine oxidation. The Se / PGE displayed a stable amperometric response with a linear concentration range of 1 μM-50 mM, the limit of quantification (LOQ) of 90 nM, and the limit of detection (LOD) 45 nM, and the sensitivity of 0.813 μA.μM−1.cm-2. Moreover, Se / PGE showed a negligible response towards common interferences like NO3 2-, CH3COO-1, phenol, and DMF at the selected applied potential. Applying the as-fabricated sensor to detect hydrazine in real samples showed satisfactory results with a recovery percentage of 96.8%. Thus, Se / PGE was successfully utilized for environmentally friendly, economical, and efficient sensing of hydrazine in water bodies. Further, our methodology paves the way for the fabrication of modified pencil graphite electrodes through the CBD method.