Synergistic on engineering layered N-doped carbon/MXene heterostructure: A potential scaffold for simultaneous electrochemical detection of Cu2+ and Hg2+ ions

Abstract

The presence of heavy metal ions (HMIs) like Cu2+ and Hg2+ in natural water and foods is a major health and environmental concern. Thus advanced electrochemical sensors are required to monitor these ions. Herein, we introduce a nitrogen-rich carbon-MXene composite (layered N-doped carbon/MXene) as an electrochemical sensor suitable for the simultaneous detection of Cu2+ and Hg2+. Synthesizing 2D/2D heterostructure interfaces using controlled thermal decomposition conditions with the incorporation of quaternary nitrogen from choline chloride and the formation of hydrogen bonds of urea within the MXene (Ti3C2Tx) provided active surfaces area that is suitable for the detection of Cu2+ and Hg2+. The intermediate structure of layered N-doped carbon/MXene, had a nitrogen content of similar to 6 %, maximized sensitivity for Cu2+ and Hg2+. The layered N-doped carbon/MXene composite exhibited excellent electrochemical sensing for Cu2+ and Hg2+ in 0.1 M acetate buffer at low sensing potentials. The limits of detection (LODs) of layered N-doped carbon/MXene were 0.019 and 0.056 mu M with a sensitivity of 114.54 and 64.317 mu A mu M-1 cm(-2) for Cu2+ and Hg2+, respectively. Furthermore, the layered N-doped carbon/MXene heterostructure exhibited high selectivity for Cu2+ and Hg2+ in the presence of potentially interfering common metal ions. This study introduces a promising advanced material for rapid Cu2+ and Hg2+ detection in food and environmental applications.