Barium-nickel-doped aluminum oxide (Al₂O₃) nanocomposite for enhanced detection of 4-nitrophenol

The release of harmful organic pollutants, including nitrophenols, from industrial waste poses significant environmental and health hazardous. This study describes the design, development and characterization of a highly sensitive and selective electrochemical sensor for the detection of 4-nitrophenol. The sensor’s working electrode is based on a novel ternary composite material consisting of barium, nickel, and aluminum, which was comprehensively characterized using a multi-technique approach, including electron microscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR), Electrochemical evaluations revealed the sensor’s excellent electrocatalytic performance, with a sensitivity of 0.90 μM/12.64 μM cm⁻², a detection limit of 7.81 μM, and a low limit of quantification (LOQ) of 2.39 μM, making it a desirable option for the sensitive and precise detection of 4-nitrophenol. Furthermore, the sensor demonstrated high stability, durability, and precision, rendering it a reliable analytical tool for detecting nitroaromatic compounds in environmental matrices. This research provides a novel framework for the development of highly sensitive and accurate sensors for environmental monitoring applications.