Facile SrO nanorods: an efficient and alternate detection approach for the selective removal of 4-aminophenol towards environmental safety

Abstract

Herein, a selective 4-aminophenol (4-AP) sensor developed using a glassy carbon electrode (GCE) decorated with wet-chemically (precipitation) prepared SrO nanorods (NRs) is investigated. The synthesized NRs were characterized by X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). To fabricate the working electrode for the desired 4-AP sensor, the GCE was coated with thin layer of SrO NRs, and stabilized with few drops of Nafion (5% suspension in ethanol) adhesive. For the calibration of this 4-AP sensor, a calibration curve was established from the linear relation of current versus concentration of 4-AP over the concentration range of 0.1 nM to 0.01 mM known as the linear dynamic range (LDR) and well fitted with the equation y = 0.6808x + 32.735 (slope = 0.6808 μA μM⁻¹). The sensor sensitivity (21.5443 μA μM⁻¹ cm⁻²) was calculated from the slope of LDR and surface area of the GCE (0.0316 cm²). The lower limit (95.76 ± 4.79 pM) for 4-AP detection was obtained at a signal-to-noise ratio of 3. The analytical parameters of the sensor such as reproducibility, response time and long-time stability are appreciable. It also shows reliability in analyses of various environmental samples.