title: Anion-Exchange Induced Strong π-π Interactions in Single Crystalline Naphthalene Diimide for Nitroexplosive Sensing: An Electronic Prototype for Visual on-Site Detection.
abstract: A new derivative of naphthalene diimide (NDMI) was synthesized that displayed optical, electrical, and visual changes exclusively for the most widespread nitroexplosive and highly water-soluble toxicant picric acid (PA) due to strong π-π interactions, dipole-charge interaction, and a favorable ground state electron transfer process facilitated by Coulombic attraction. The sensing mechanism and interaction between NDMI with PA is demonstrated via X-ray diffraction analysis, (1)H NMR studies, cyclic voltammetry, UV-visible/fluorescence spectroscopy, and lifetime measurements. Single crystal X-ray structure of NDMI revealed the formation of self-assembled crystalline network assisted by noncovalent C-H···I interactions that get disrupted upon introducing PA as a result of anion exchange and strong π-π stacking between NDMI and PA. Morphological studies of NDMI displayed large numbers of single crystalline microrods along with some three-dimensional (3D) daisy-like structures which were fabricated on Al-coated glass substrate to construct a low-cost two terminal sensor device for realizing vapor mode detection of PA at room temperature and under ambient conditions. Furthermore, an economical and portable electronic prototype was developed for visual and on-site detection of PA vapors under exceptionally realistic conditions.
authors: Center for Nanotechnology and ‡Department of Chemistry, Indian Institute of Technology , Guwahati-781039, Assam, India.
authors: Anamika
authors: A
authors: Kalita
authors: Center for Nanotechnology and ‡Department of Chemistry, Indian Institute of Technology , Guwahati-781039, Assam, India.
authors: Sameer
authors: S
authors: Hussain
authors: Center for Nanotechnology and ‡Department of Chemistry, Indian Institute of Technology , Guwahati-781039, Assam, India.
authors: Akhtar Hussain
authors: AH
authors: Malik
authors: Center for Nanotechnology and ‡Department of Chemistry, Indian Institute of Technology , Guwahati-781039, Assam, India.
authors: Ujjwol
authors: U
authors: Barman
authors: Center for Nanotechnology and ‡Department of Chemistry, Indian Institute of Technology , Guwahati-781039, Assam, India.
authors: Namami
authors: N
authors: Goswami
authors: Center for Nanotechnology and ‡Department of Chemistry, Indian Institute of Technology , Guwahati-781039, Assam, India.
authors: Parameswar Krishnan
authors: PK
authors: Iyer
keywords: electronic prototype; nitroexplosives; sensing; single crystalline naphthalene diimide; vapor-mode; π−π interactions