One-pot hydrothermal synthesis of parkerite-type nickel bismuth selenide (Ni₃Bi₂Se₂) nanogranules for selective enzyme-free urea sensing

The investigation of electrode materials for urea level determination (non-enzymatic) is advantageous to monitor patient’s clinical health and prevention of milk adulteration. Chalcogenides have prospective applications in electrocatalysis because of their fast charge transfer and large specific surface area in terms of non-enzymatic sensing via redox reactions, which is of great significance. However, despite their tremendous relevance, they continue to present significant problems. To address this issue, a new parkerite-type compound, Ni₃Bi₂Se₂, was synthesized using the capping agent sodium laurel sulfate through a hydrothermal process. The physical characterization of the ternary chalcogenide Ni₃Bi₂Se₂ was done by X-ray photoelectron spectroscopy, scanning electron microscopy, powder X-ray diffraction, and photoluminescence. The analytical performances of the suggested sensor electrode, including sensitivity, the limit of detection (LOD), limit of quantification (LOQ), stability, and durability, were obtained by various electrochemical techniques. The lower limit of detection (LOD-6.05 µM), sensitivity (10.9 mA µM⁻¹ cm⁻²) and lower limit of quantification (LOQ-18.35 µM) were derived using the calibration curve. Moreover, it provides accurate results when detecting urea in human urine samples. The prepared electrode shows outstanding sensitivity, selectivity, superior reproducibility, and long-term stability.