Green synthesis approach to produce TiO2/rGO nanocomposite as voltammetric sensor for monitoring trace level bisphenol-A

Abstract

The detection of trace level bisphenol-A (BPA) in plasticware has been successfully performed using a novel green-TiO2/rGO which was studied using electrochemical process. The green-TiO2/rGO was synthesized through green technique via one-pot synthesis using green-tea extract. The synthesized green-TiO2/rGO as sensors was characterized by fourier transform infra-Red (FTIR), X-ray Diffraction (XRD), electrochemical impedance spectroscopy (EIS), scanning electron microscope (SEM), and transmission electron microscopy (TEM). SEM image revealed that TiO2 successfully grew on rGO sheets in nanoscale (∼112 nm) with crystallite size of ∼7 nm from XRD diffractogram calculation. Then, the electrochemical activity was measured by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) in a 0.01 M [Fe(CN)6]3–/4– in 0.1 M NaCl. The composition, pH, and scan rate effects were investigated for the optimum electrochemical process. TiO2/rGO modified CPE showed good linearity, repeatability, and accuracy with the LOD of 0.08 µM and the linearity range of 1–200 µM. The performance of the voltammetry method was very excellent a resulting similar amount of BPA detection in the actual samples compared with HPLC technique with the recovery range (%) of 98.99 ± 0.52 to 102.95 ± 1.18.