High nitrogen-doped carbon nanosheets for electrochemical sensing of malachite green

The facile fabrication of doped carbon materials with multiple functions has been a challenging issue in materials science. Herein, nitrogen-doped carbon nanosheets with high doping level (32.05 wt%) were obtained by one-step calcination with urea and polyaniline as precursors. The presence of abundant edges and crimp, and the increase of the proportion of pyrrolic and graphitic nitrogen promote the exposure of the active site of the doped nanosheets. These structural advantages result in a favourable electrochemical response to organic pollutant malachite green. The linear range of detection of malachite green is 1 ∼ 10 μmol/L and the limit of detection is 13.2 nmol/L by differential pulse voltammetry electrochemical sensor constructed with high nitrogen- doped carbon nanosheets. The electrochemical sensor showed a satisfactory recovery rate for malachite green detection in actual tap water sample. This work offers a constructive solution for the facile fabrication and chemical sensor application of doped two-dimensional carbon-based materials.