Fabrication of Highly Sensitive Phenyl Hydrazine Chemical Sensor based on as-grown ZnO-Fe2O3 Microwires

As-grown ZnO-Fe2O3 microwires were prepared by a wet-chemical process using reducing agents in alkaline medium and characterized by UV/vis., FT-IR, Raman, electron-dispersive (EDS) spectroscopy, powder X-ray diffraction (XRD), and field-emission scanning electron microscopy (FESEM). They were deposited on a gold electrode (AuE, surface area, 0.0216 cm2) to fabricate a chemi-sensor with a fast response towards toxic phenyl hydrazine (PhHyd) chemical in phosphate buffer solution (PBS). The chemi-sensor was also exhibited higher sensitivity and long-term stability, 2 and enhanced electrochemical response towards toxic PhHyd. The calibration plot was linear (r2 = 0.9389) over the 1.0 nM to 10.0 mM PhHyd concentration ranges. The sensitivity and detection limit were calculated about 8.33 μAcm-2mM-1 and 0.67 ± 0.05 nM (signal-to-noise ratio, at a SNR of 3) respectively. Here the possible future prospective uses of the ZnO-Fe2O3 microwires in terms of chemical sensing are discussed.