Selenium Nanoneedles Deposited on a Pencil Graphite Electrode for Hydrazine Sensing
Sumaya Ishtiaq, Manzar Sohail, Shahid Rasul, Abdul Wasy Zia, Lidija Šiller, Ghayoor Abbas Chotana, M. Sharif, Ayman Nafady
Abstract
The low toxicity of Se nanoparticles (NPs) makes it a suitable candidate for biomedical and sensing applications. Herein, we, for the first time, report the modification of a pencil graphite electrode with Se nanostructures (Se/PGE) by a facile chemical bath deposition (CBD) method. Hydrazine, a routine chemical in various industries, is toxic even in trace amounts and poses a serious threat due to its carcinogenic and mutagenic nature. Therefore, it is crucial to detect its presence in aqueous media. The Se/PGE exhibited outstanding, reproducible, and selective electrocatalytic activity for hydrazine determination. The Se/PGE displayed a stable amperometric response with a wide linear concentration range of 1 μM–50 mM, a LOQ of 90 nM, a very low LOD of 45 nM, and a sensitivity of 0.813 μA·μM–1·cm–2. Moreover, Se/PGE showed a negligible response toward common interferences like NO3–1, CH3COO–1, phenol, and DMF at the selected applied potential. Applying the as-fabricated sensor for hydrazine detection in real-life samples (drinking water) showed satisfactory results with a recovery percentage of 96.9%. Further, our methodology paves the way to fabricate modified pencil graphite electrodes (PGEs) through a convenient CBD method.