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

This work reports a fine-grained flower like NiO/NiCo 2 O 4 dual-phase composite derived from bimetallic LDH for ultra-sensitive and trace level detection of roxarsone (ROX) sensor. The flower like NiO/NiCo 2 O 4 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 NiCo 2 O 4 . Various characterization techniques are utilized to characterize the crystallinity and morphological properties of the NiO/NiCo 2 O 4 composite. The high surface area and efficient electron transfer properties of NiO/NiCo 2 O 4 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/NiCo 2 O 4 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 cm 2 . 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/NiCo 2 O 4 composite, which holds potential for a wide range of future applications with effectively detecting contaminated food products. • Fine-grained flower-like NiO/NiCo 2 O 4 dual-phase composite was derived from LDH. • The NiO/NiCo 2 O 4 offers a wide linear range with an LOD of 2.3 nM for ROX detection. • ROX sensor by NiO/NiCo 2 O 4 achieved good selectivity, stability, and reproducibility. • The real-time applicability of NiO/NiCo 2 O 4 retains good recovery in chicken and water samples.