Selective detection and removal of picric acid by C2N surface from a mixture of nitro-explosives

Abstract

Nitro-explosives are a severe threat to the environment; therefore, detection and removal of nitro-explosives is the need of time. Herein, we illustrate the application of a newly discovered C₂N surface for electrochemical detection and removal of nitro-explosives: namely, picric acid (PA), ethyleneglycoldinitrate (EGDN), and dimethyldinitrobutane (DMNB). Among the studied analytes, the highest adsorption energy of −25.12 kcal mol⁻¹ (BSSE = −18.48 kcal mol⁻¹) was observed for the PA@C₂N complex. The nature of interactions was further quantified by SAPT0, NCI and QTAIM analyses, while the electronic properties were studied through EDD, NBO and FMO analyses. The SAPT0 analysis reveal that the dispersion factor remained dominant (60–64%) for stabilization of analyte@C₂N complexes. The highest charge transfer was observed for PA@C₂N (0.01e⁻), whereas the least amount of charge transfer was calculated for DMNB@C₂N (−0.004e⁻). A more pronounced change in the E_H–L gap was observed for PA@C₂N (3.07 eV) compared to the DMNB@C₂N (3.66 eV) and EGDN@C₂N complexes (3.68 eV). It was noticed that a potential decrease in the E_H–L gaps can be observed when the electronic transition occurs from the analyte to the C₂N surface. The recovery time of PA is 35 s (298 K), which shows that the sensor can be easily recovered under ambient conditions. The results of various parameters reveal that C₂N is more selective towards PA than toward the other studied analytes.