Rationally designed flower like NiO/NiCo₂O₄ dual-phase composite for ultrasensitive detection of roxarsone sensor

This work reports a fine-grained flower like NiO/NiCo₂O₄ dual-phase composite derived from bimetallic LDH for ultra-sensitive and trace level detection of roxarsone (ROX) sensor. The flower like NiO/NiCo₂O₄ dual-phase composite was prepared via a novel single-step approach that can simultaneously control NiO morphology and dual-phase formation of mixed metal oxide with NiCo₂O₄. Various characterization techniques are utilized to characterize the crystallinity and morphological properties of the NiO/NiCo₂O₄ composite. The high surface area and efficient electron transfer properties of NiO/NiCo₂O₄ composite can improve the sensor's sensitivity towards the detection of ROX, achieving fast response even in low concentrations. The experimental results emphasize notable variation in the peak current changes via electrochemical impedance spectroscopy and cyclic voltammetry. Preliminary findings of this ROX sensor using NiO/NiCo₂O₄ composite imply a wide linear range of 0.01-314.1 μM, alongside a promising limit of detection (LOD) of 2.3 nM with a higher sensitivity of 2.22 μA μM^-1 cm². In addition, the proposed ROX sensor offered more reliable in chicken and water samples for real-time analysis combined with appropriate recovery ranges of 98.15-99.83 %. Furthermore, the electrochemical results emphasized the excellent electrochemical stability including its reproducibility, repeatability, and fast response towards ROX. This study opens new era for fabricating highly effective NiO/NiCo₂O₄ composite, which holds potential for a wide range of future applications with effectively detecting contaminated food products.