Nitrogen and phosphorus co-doped porous carbon framework with superior electrochemical activity for naphthol isomers sensing

Abstract

Heteroatom-doped carbon has emerged as one of the most important electrode materials for electrochemical analysis. Thus, designing and synthesizing novel heteroatom-doped carbon material with superior electrochemical activity is highly desired. Herein, we report a simple and effective pyrolysis-activation strategy to synthesize nitrogen and phosphorus co-doped porous carbon (N, P–C) framework by using zeolitic imidazolate framework-67 (ZIF-67) as the precursor and phytic acid as the phosphorus source. It is found that the surface defect level, electrochemical active area and electrode reaction kinetics of N, P–C framework is greatly boosted compared with ZIF-67 derived N-doped porous carbon (N–C) framework. These features endow N, P–C framework with outstanding electrochemical activity for the oxidation of highly toxic environmental pollutants 1-naphthol and 2-naphthol. The oxidation peak currents of 1-naphthol and 2-naphthol increase linearly in the range from 25 nM to 2 μM. Besides, the limits of detection are estimated to be about 8.0 nM and 7.2 nM (three signal-to-noise ratio) for 1-naphthol and 2-naphthol with sensitivity of 87.3 μA μM−1 cm−2 and 84.6 μA μM−1 cm−2, respectively.