2-Nitrophenol sensor-based wet-chemically prepared binary doped Co 3 O 4 /Al 2 O 3 nanosheets by an electrochemical approach.

Herein, the wet-chemical process (co-precipitation) was used to prepare nanosheets (NSs) of Co 3 O 4 /Al 2 O 3 in an alkaline medium (pH ∼ 10.5). The synthesized NSs were totally characterized by Fourier-transform infrared spectroscopy (FTIR), ultraviolet visible spectroscopy (UV/vis), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and powder X-ray diffraction (XRD). The synthesized NSs were deposited onto a glassy carbon electrode (GCE) to prepare a very thin layer with a conducting binder for detecting 2-nitrophenol (2-NP) selectively by a reliable electrochemical method. The proposed chemical sensor exhibits good sensitivity (54.9842 μA μM -1 cm -2 ), long-term stability, and enhanced chemical response by electrochemical approaches. The resultant current is found to be linear over the concentration range (LDR) from 0.01 nM to 0.01 mM. The estimated detection limit (DL) is equal to 1.73 ± 0.02 pM. This study introduces a potential route for future sensitive sensor development with Co 3 O 4 /Al 2 O 3 NSs by an electrochemical approach for the selective detection of hazardous and carcinogenic chemicals in environmental and health care fields.