The trace detection of energetic materials (EMs) is a challenge due to the very low vapor pressure possessed by these compounds. Polyaniline (PAni) possesses variable oxidation and reduction states, which makes it strike different from other conducting polymers in understanding the mechanism of fluorophore‐analyte interaction leads to the designing of selectivity and sensitivity of analytes; also, fluorophore as a sensing device. The present work is aimed at trace detection of some very prominent EMs; nitroarenes viz., 1,3,5‐trinitroperhydro‐1,3,5‐triazine (RDX), trinitrotoluene (TNT); nitramines viz., hexanitrohexaazaisowurtzitane (CL‐20) and nitro ester viz., pentaerithroltetraniterate (PETN) employing para‐toluenesulfonic acid as a dopant for PAni nanofibers (P‐PAni). The P‐PAni helps overcome the dual difficulties of PAni, i.e., solubility and removal of π stacking when dimethylformamide (DMF) is used as a solvent. P‐PAni showed good quenching response and selectivity towards EMs, with the LOD being the best for CL‐20 (0.717 μM·L–1). The sensing studies further collaborated with the Cyclic Voltammetry, FTIR and Raman Spectroscopy studies gave a detailed understanding of the bipolaron‐polaron transition mechanism accompanying the electron transfer process in the fluorescence quenching study.

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The Fluorescence sensing technique for trace detection of High Energy Materials (HEMs) has gained more attention in recent times. In the present paper, the interaction between the fluorophore and HEMs is studied using spectroscopic and electrochemical techniques. The fluorophore polyaniline (PANI) was functionalised by doping it with benzenesulfonic acid (BSA) to increase the processability, and mobility of p-electrons along with decreased p-stacking. It is observed that upon doping the solubility of BSA-PANI is increased, facilitating a higher quenching by commercial explosives, i.e., RDX, CL-20, CL-20:RDX cocrystal. The interaction studies undertaken though fluorescence quenching, FTIR and Resonance Raman studies shows that the benzenoid unit, polaron and bipolaron nitrogen in BSA-PANI interact with nitro groups of HEMs and form a charge-transfer complex between HEMs and BSA-PANI undergoing predominantly a PET mechanism. LOD value is found to be least for Cocrystal (1.876 9 10 -5 M) when compared to other HEMs 3.191 9 10 -5 M (CL-20), 5.904 9 10 -5 M (RDX), 3.734 9 10 -5 M (PETN) indicating that cocrystal can be detected in trace level. The collaborative study between cyclic voltammetry and