MnCo2O4 decorated (2D/2D) rGO/g-C3N4-based Non-Enzymatic sensor for highly selective and sensitive detection of Chlorpyrifos in water and food samples

Abstract

An effective and accurate detection of Chlorpyrifos (CPS), a well-known organophosphorus pesticide became essential in our modern world to control environmental pollution. Analytical detection of CPS is recommended for appropriate environmental supervision and to elude all health-related problems in smoke-stock spheres. To achieve this goal, an ecofriendly and one step combustion route for the synthesis of reduced graphene oxide-graphitic carbon nitride (rGO/g-C 3 N 4 ) 2D/2D modified manganese cobaltite (MnCo 2 O 4 ) nanocomposite was designed in this study. With the combination of properties like relatively larger surface area of rGO/g-C 3 N 4 and excellent conductivity and good biocompatibility of rGO along with MnCo 2 O 4 nanoparticles, a highly sensitive CPS sensor was aimed. The nanocomposite was identified using Powder x-ray diffraction (PXRD), Field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), Raman Spectroscopy and BET analysis. In the TEM image, a distinct surface of the g-C 3 N 4 can be seen which acts as a bridge between rGO layers and MnCo 2 O 4 nanoparticles. Highest conductivity of the nanocomposite was showcased using the electronic impedance spectroscopy (EIS) technique that supported the idea of being a potential sensor material. Under optimum environment, the designed non-enzymatic electrochemical sensor was able to sense CPS at lower detection limit (LOD) of 0.14 × 10 −12 M (0.322 × 10 −6 μg/ml) with a wider range of 20 μM to 30 pM at room temperature. Furthermore, the present sensor showed desirable selectivity and superior stability with good reproducibility indicating its effective sensing capability for environmentally toxic CPS pesticide.