Silver cluster decorated graphene nanoflakes for selective and accurate detection of nitroaniline isomers; DFT calculations

Abstract

DFT study is carried out to explore silver cluster decorated graphene sensors for the selective and accurate detection of poor biodegradable and highly toxic nitroaniline isomers. In current study the most stable structures are evaluated through interaction energies (Eint), NBO charge transfer (QNBO), HOMO-LUMO gap, UV–Visible, NCI and CDA analyses. The stability order of nitroaniline complexes is analyte@Ag6-coronene > analyte@Ag6 > analyte@coronene > analyte@coronene-Ag6. The higher stability of analyte@Ag6-coronene complexes is due to dominating Ag⋯O electrostatic interactions. The higher NBO charge transfer from analyte towards substrate is observed in the complexes where analyte directly interacts with Ag6 surface. Highest QNBO transferred (−1.369 e−) and highest interaction energy (−172.42 kJ/mol) are observed in meta-Nitroaniline@Ag6-coronene complex. DOS spectra reveal that both analyte and Ag6 mainly contribute to energy of highest occupied molecular orbitals. NCI results advocate the presence of electrostatic and van der Waals interactions besides steric clashes in analyte@silver-coronene complexes. The evaluated results authenticate the excellent sensing ability of silver-graphene composites for the selective and accurate detection of nitroaniline isomers. The upshot of the current findings and its prospects will be a smart choice for sensor development in near future.