Construction of nickel cobalt-layered double hydroxide/functionalized–halloysite nanotubes composite for electrochemical detection of organophosphate insecticide

Abstract

• A novel electrochemical sensor based on NiCo-LDH/F-HNTs was proposed. • The proposed NiCo-LDH/F-HNTs sensor was used for determination of ethyl parathion. • Highly sensitive and selective determination of ethyl parathion with trace level LODs in nanomolar range. • This sensor was successful for determination of ethyl parathion in real samples. The development of electrode materials with swift response has always been a crucial need for the safety of many foods and environmental applications. Herein, we demonstrate a one-pot hydrothermal approach to synthesize a hybrid nickel cobalt-layered double hydroxide/ functionalized halloysite nanotubes (NiCo-LDH/F-HNTs) composite for the electrochemical detection of parathion (PT). The physicochemical and structural characterizations of the prepared NiCo-LDH/F-HNTs composites were meticulously investigated for detailed understanding. Experimental results confirm that the NiCo-LDH/F-HNTs modified electrode shows high electrochemical efficiency for the PT reduction compared to other electrodes. This enhanced activity is attributed to the synergistic effect, numerous active sites, high conductivity, large specific surface area, rapid electron transfer of NiCo-LDH/F-HNTs composite. After parameter optimization, the NiCo-LDH/F-HNTs based electrochemical sensor provides the superior performance, such as a wide linearity range from 0.01 to 33.4 µM, the limit of detection as low as 0.002 µM, the sensitivity as high as 13.0 µA µM −1 cm −2 , good selectivity and excellent reproducibility. Besides, the real-time detection of PT in environmental samples also shows satisfactory results. Overall, our work provides an approach for the design and development of electrochemical sensors for trace-level PT analysis with facile fabrication, high activity, and good reliability.