A tetraphenylcyclopentadiene based multifunctional, solution processable, fluorescent, ultramicroporous polymer exhibiting high hydrogen uptake was employed for encapsulation of dyes to obtain enhanced white light emission in solution, nanoparticles, gel and transparent thin film. Hybrid nanoparticles showed a quantum yield of 35% with a high color rendering index.

White light emitting (WLE) materials are of increasing interesto wing to their promising applicationsi na rtificial lighting, display devices, molecular sensors, and switches.I n this context,o rganic WLE materials cater to the interesto f the scientific community owing to their promising features like color purity,l ong-term stability,s olutionp rocessability, cost-effectiveness,a nd low toxicity.T he typical methodf or the generation of white light is to combine three primary (red, green, and blue) or the two complementary (e.g., yellow and blue or red and cyan) emissive units covering the whole visible spectralw indow (400-800 nm). The judicious choice of molecular buildingb locks and connecting them through either strong covalentb onds or assembling through weakn oncovalent interactions are the key to achieve enhanced emissions panning the entire visible region.In the present review article, moleculare ngineering approaches for the development of all-organic WLE materials are analyzed in view of different photophysical processes like fluorescencer esonance energy transfer (FRET), excitedstate intramolecular protont ransfer (ESIPT), charget ransfer (CT), monomer-excimer emission, triplet-state harvesting, etc. The key aspect of tuning the molecular fluorescence under the influence of pH, heat, and host-guest interactions is also discussed. The white light emission obtained from small organic molecules to supramolecular assemblies is presented,i ncluding polymers, micelles,a nd also employing covalent organic frameworks. The state-of-the-art knowledge in the field of organic WLE materials, challenges, and future scope are delineated.

The excited-state intramolecular proton transfer (ESIPT)-based molecular probes have drawn significant attention owing to their environment-sensitive fluorescence properties, large Stokes shift, and emerged as building blocks for the development of molecular sensors and switches. However, most of the ESIPT-based fluorophores exhibit weak emission in the solid state limiting the scope of real-time applications. Addressing such issues, herein, we presented a C 3 symmetric-like molecular architecture employing a simple one-step Schiff base condensation between triaminoguanidinium chloride and 3,5-di-tert-butyl-2-hydroxybenzaldehyde (TGHB). The temperature-dependent fluorescence studies including at 77 K indicated the strong emission from the keto tautomer compared to that of the enol tautomer. The facile ESIPT in TGHB in the solid-state led to a remarkable enhancement of fluorescence quantum yield of 1600 times compared to that of the solution (λ em = 545 nm) by restricting the intramolecular rotation and subsequently suppressing the nonradiative deactivation. The excited-state processes were further elucidated through time-resolved fluorescence measurements. TGHB exhibited turn on−off fluorescence upon exposure to acid/base vapor in the form of a powder as well as a transparent, freestanding thin film. A rewritable and erasable fluorescent platform was demonstrated using TGHB as molecular ink, which offers a potential testbed for performing "write-erase-write" cycles multiple times. In addition, TGHB, possessing multiple binding sites (O and N donors) involving the central core of the triaminoguanidinium cation displayed selective turn-on fluorescence with Zn 2+ . The structure−property relationship revealed in the present study provides insight into the development of novel cost-effective multifunctional materials, which are promising for stimuli-responsive molecular switches.

Tetraphenyl-5,5-dioctylcyclopentadiene based porous organic polymers were fabricated in the form of powder, soluble in organic solvents and nanoparticles and were explored for gas adsorption and chemosensing.