Abstract
•The NiFe-LDH/Mo2C nanocomposite is successfully synthesized by hydrothermal method.•The NiFe-LDH /Mo2C based sensor owns excellent electrocatalytic activity for NO2–.•Excellent performance includes ultralow LOD, high sensitivity and good selectivity.•The proposed sensor is successfully used for NO2– detection in the actual samples.
We fabricate a novel hierarchical system of NiFe-layered double hydroxide (LDH)/Mo2C nanocomposite through environmentally friendly deep eutectic solvents (DESs) by the solvothermal method and utilize it as an electrochemical platform for NO2– detection. The NiFe-LDH/Mo2C modified glassy carbon electrode (GCE) demonstrates a low oxidation potential of +0.82 V (vs Ag/AgCl (Sat. KCl)) in the phosphate-buffered electrolyte of pH 7.0, suggesting superior performance compared to un-modified and other modified GCEs. The proposed nitrite sensor exhibits a wide working range from 0.005 to 260 μM with a low limit of detection of 0.0017 μM and sensitivity of 3.6 µA µM−1 cm−2, demonstrating almost the most remarkable performance enhancement compared to those reported in the literatures. Importantly, the obtained performance is well below the guideline level of NO2– set by the World Health Organization. Furthermore, the proposed electrochemical sensor exhibits good selectivity, stability, reproducibility, and excellent suitability for the real samples towards NO2– detection. This approach may hold the promise for the construction of DESs derived 2D interfacial nanocomposite for electrochemical applications.