A very rare fluorescent chemosensor of zinc(II) exhibiting AIEE, ESIPT and TICT: Spectroscopic, crystallographic and theoretical exploration.

The basic systems in this study are HL (1; 1:2 condensation product of 2,6-diformyl-4-ethylphenol and o-anisidine) and its ZnII and CdII complexes of composition [ZnII(LH)Cl2]·CH3OH (2) and [CdII(LH)Cl2] (3), all of which are synthesized and characterized by CHN elemental analyses, single crystal X-ray crystallography, powder X-ray diffraction (PXRD) and fourier transform infrared (FT-IR) spectrum. It has been established from the following experimental and theoretical studies that 1 is a fluorescent turn on sensor of ZnII ion and it exhibits all of excited state intramolecular proton transfer (ESIPT), photoinduced electron transfer (PET), twisted intramolecular charge transfer (TICT) and aggregation induced enhanced emission (AIEE): (i) Detailed absorption and emission (steady state / time resolved) studies in various single solvents, in solvent mixtures, with pH variation, with various single metal ions, with mixtures of metal ions, on varying temperature and on varying viscosity; (ii) dynamic light scattering (DLS) and scanning electron microscopy (SEM) in solvent mixtures; (iii) density functional theory (DFT) and time dependent density functional theory (TD-DFT) calculations in ground and excites states of 1-3. It is shown that 1 can be efficaciously applied in inkless writing with the "write - erase - write" facility. The mechanisms/reasons of the observed properties have been addressed. The difference in fluorescence of ZnII and CdII complexes, unusual case of crystal structures of probe and complexes with ZnII and CdII, unusual features in the structures of 2 and 3 as well as a structure-property correlation have been discussed.

Enabling Ultrahigh Surface Area of Covalently-linked Organic Framework for Boosted CO2 Capture: An Air Liquid Interfacial Plasma as Post-furnishing Protocol.

The cognitive intent of a highly ordered and robust adsorbent is extremely sensible and, in this context, Covalent Organic Framework (COF) materials have significantly burgeoned their scope in diverse applications. Herein, a simple time-competent hydrothermal procedure is presented to construct a covalent framework with an ultrahigh surface area of 1428 m2 /g that shows active adsorption of carbon dioxide (CO2 ) at variable temperature ranges. Moreover, a facile scalably controlled post-synthetic air liquid interfacial plasma (ALIP) induced protocol is substantiated that explicitly amplifies the surface area of the pristine framework even to a higher value of 2051 m2 /g. The post-synthetic plasma approach presented here led to the rapid enhancement of the surface area of the pristine COF by 43 %, which concurrently advances the CO2 uptake up to 67 %. Hence, the current study may open up a new frontier in the design as well as fine-tune the properties of the covalent framework that unfolds the advanced outlook in addressing the challenges of CO2 capture.