Microwave aided synthesis of samarium hafnate pyrochlore-sulphur doped reduced graphene oxide for electrochemical detection of bendiocarb

Abstract

The current study reports the synthesis of pyrochlore type Sm2Hf2O7 (SHO) and its nanocomposite with sulfur-doped reduced graphene oxide (SR). SHO/SR nanocomposite was synthesized using a simple hydrothermal method followed by a microwave-aided synthetic method. Morphological investigations indicate that long SHO particles are well-aggregated in the wrinkled two-dimensional SR. Modified the glassy carbon electrodes (GCE) using SHO, SR and SHO/SR and evaluated for the electrochemical detection of an insecticide, bendiocarb (BDC). Enhanced electrochemical performance was observed in SHO/SR@GCE compared to SHO and SR. Superior electrochemical performance in SHO/SR could be attributed to enhanced conductivity, surface area and stability. Differential pulse voltammetry (DPV) technique showed good sensitivity, and the observed range is 0.05 to 300 μM with a 0.671 μM limit of detection (LOD). In addition, DPV technique is used for the detection of BDC in tomatoes and cabbage, finding a good percentage recovery (97.12 to 99.47 %) with less than 2.65 % relative standard deviation (RSD). The stability of the SHO/SR@GCE was good, and the current response retention was found to be 88.6 ± 1.93 % even after twenty days. SHO/SR's versatile structure, stability, conductivity, and surface area make it an ideal material for developing pyrochlore-based materials for electrochemical and energy applications.