An Electrochemical Sensor Based on 3D Graphene‐Cyclodextrin Nanohybrid for Enhanced Sensitivity Detection of Nitroaromatic Compounds

This study presents an electrochemical sensor for sensitive detection of nitroaromatic compounds using a three‐dimensional (3D) porous graphene with polyoxypropylene supported reduced graphene oxide (PEA‐RGO) and embedded β‐cyclodextrins (β‐CD). First, PEA‐RGO was synthesized by the condensation reaction between graphene oxide (GO) and amino‐terminated polyoxypropylene (PEA), followed by hydrazine hydrate reduction. Then, β‐CD was embedded into the porous of the above 3D graphene to obtain PEA‐RGO/β‐CD nanohybrid. Various characterization techniques, such as microscopy imaging, infrared spectrometry, thermal analysis and electrochemical measurements, were employed to confirm the successful synthesis and unique 3D architecture structure of PEA‐RGO/β‐CD. Afterwards, the glassy carbon electrode (GCE) was modified by PEA‐RGO/β‐CD, and its electrochemical detection performances were investigated for detecting nitroaromatic compounds, including nitrobenzene (NB), 2‐nitroaniline (2‐NA), 2‐chloronitrobenzene (2‐NCB), and 2‐nitrophenol (2‐NP). The results of electrochemical measurements exhibited relative higher sensitivities (1.88 μA/μM/cm 2 for NB, 2.13 μA/μM/cm 2 for 2‐NA, 2.35 μA/μM/cm 2 for 2‐NP, 0.83 μA/μM/cm 2 for 2‐NCB, respectively) and lower limits of detection (LOD) (39.4 nM for NB, 44.6 nM for 2‐NA, 75.6 nM for 2‐NP, 69.6 nM for 2‐NCB, respectively). Additionally, the proposed sensor was also applied in detection in real samples with recovery range of 88.13%–109.52 %. The enhanced detecting performances can be attributed to the synergistic effect of the high conductivity from RGO, recognition capabilities from β‐CD, and excellent properties from 3D structure. The present work would provide a robust tool for environmental monitoring and the detection of nitroaromatic pollutants.