Defect-rich hexagonal boron nitride for the simultaneous determination of 4-aminophenol and phenol

Abstract A new electrochemical sensor has been developed for the simultaneous determination of 4-aminophenol (4-AP) and phenol (Ph) based on the defect-rich hexagonal boron nitride (D-h-BN). The D-h-BN was prepared via one-step calcination route using a single-source precursor. The obtained D-h-BN was structurally characterized by X-ray diffraction (XRD), fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM). Photoluminescent (PL) result suggested that the as-synthesized h-BN was highly defective. More interestingly, such D-h-BN exhibited favorable electrocatalytic activity in the redox reaction of Ph and 4-AP, which was confirmed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) measurements. The enhanced electrocatalytic activity of D-h-BN was attributed to its large surface-active sites and fast electron transfer mediated by defect structure. Thus, D-h-BN was employed to modify glassy carbon electrode (GCE) without any binder agents and the as-fabricated sensor showed good electrochemical performances in the simultaneous determination of 4-AP and Ph. By using DPV method, the linear detection ranges between concentrations and current intensities for 4-AP and Ph were 0.01-30 and 0.1-30 µM, respectively, and their detection limits (S/N = 3) were estimated to be 0.003 and 0.035 µM. Moreover, the desirable selectivity and reproducibility make the proposed method successfully applied for real sample assay.