Picric Acid sensing by Carbon Nanodots: Theoretical Validation of Selectivity

Abstract

Carbon nanodots (CNDs), known for their exceptional properties, have become a standout member among the nanostructured carbon materials. The most appreciated application of carbon nanodots is sensing, evoked through the reflex response of fluorescence in presence of specific analytes. Herein we unveil the mechanism of selective sensing of picric acid by carbon nanodots, among a group of analogous compounds. A solid explanation for the selectivity shown by the the system among the nitrocompounds is provided with the support of DFT studies. The computed Global reactive descriptors describe the reactivities of different nitroaromatics with each other and the associated DAM simultaneously classify them to electron donor and acceptor from best to worst. Along with this data, the detailed FMO analysis clarifies the selective sensing of picric acid by CNDs, which is in complete agreement with the experimental observations. It is envisioned that this attempt would initiate drives to design CND based systems of optimum energy levels, which can perform as promising sensors for analytes of significance.