Electrochemical sensor based on $\hbox {Na}^{+}$-doped $\hbox {g-C}_{3}\hbox {N}_{4}$ for detection of phenol

Abstract

In this work, a novel and enhanced electrochemical sensor based on $\hbox {Na}^{+}$-doped $\hbox {g-C}_{3}\hbox {N}_{4}$ was constructed for the detection of phenol. First, the $\hbox {g-C}_{3}\hbox {N}_{4}$ was formed through polymerizing melamine under $520^{\circ }\hbox {C}$. And then the $\hbox {Na}^{+}$-doped $\hbox {g-C}_{3}\hbox {N}_{4}$ was fabricated by a simple wet chemical method. The electrochemical sensor was constructed by modifying the carbon paper with the resulting $\hbox {Na}^{+}$-doped $\hbox {g-C}_{3}\hbox {N}_{4}$. The morphology, chemical compositions and structure of $\hbox {Na}^{+}$-doped $\hbox {g-C}_{3}\hbox {N}_{4}$ were characterized by scanning electron microscopy, transmission electronic microscopy, energy-dispersive X-ray detector and X-ray diffraction. The $\hbox {Na}^{+}$-doped $\hbox {g-C}_{3}\hbox {N}_{4}$ electrode was used for the cyclic voltammetry and amperometric response detection of phenol in a 0.1 M phosphate buffer (pH 9.0). Under the optimal conditions, the prepared sensor displayed good performance for the electrochemical detection of phenol with a wide linear range of $1-110~\upmu \hbox {M}$, as well as low detection limit of $0.23~\upmu \hbox {M}$.