02131nas a2200301 4500008004100000022001400041245011400055210006900169260000900238490000700247520111200254653001601366653002001382653000901402653002001411653000901431100002901440700001801469700002901487700002401516700002901540700002501569700001801594700002501612700003101637700003001668856013101698 2023 eng d a1861-472800aThermally activated delayed fluorescent solvent-free organic liquid hybrids for tunable emission applications0 aThermally activated delayed fluorescent solventfree organic liqu cJUL 0 v183 a

The synthetic feasibility and excellent luminescence features of organic molecules attracted much attention and were eventually found useful in lighting applications. In this context, a solvent-free organic liquid having attractive thermally activated delayed fluorescence features in bulk along with high processability has prime importance. Herein, we report a series of naphthalene monoimide-based solvent-free organic liquids exhibiting cyan to red thermally activated delayed fluorescence with luminescence quantum yields up to 80% and lifetimes between 10 to 45 mu s. An effective approach explored energy transfer between liquid donors with various emitters exhibiting tunable emission colors, including white. The high processability of liquid emitters improved the compatibility with polylactic acid and was used for developing multicolor emissive objects using 3D printing. Our demonstration of the thermally activated delayed fluorescence liquid will be much appreciated as a processable alternate emissive material suitable for large-area lighting, display, and related applications.

10a3D printing10aEnergy Transfer10aOLED10aOrganic Liquids10aTADF1 aNidhankar, Aakash, D. D.1 aGoudappagouda1 aKothavade, Premkumar, D.1 aDongre, Sangram, D.1 aVeer, Sairam, Dnyaneshwa1 aDash, Soumya, Ranjan1 aRajeev, Kavya1 aUnni, K., N. Narayan1 aShanmuganathan, Kadhiravan1 aBabu, Sukumaran, Santhosh uhttp://library.ncl.res.in/content/thermally-activated-delayed-fluorescent-solvent-free-organic-liquid-hybrids-tunable-emission02426nas a2200277 4500008004100000022001400041245012800055210007000183260000900253490000700262520147600269653003801745653001001783653001801793653001701811653000901828100002201837700001801859700003001877700002401907700002001931700002001951700001801971700003001989856012902019 2024 eng d a0947-653900aBoron- and oxygen-doped π-extended helical nanographene with circularly polarised thermally activated delayed fluorescence0 aBoron and oxygendoped πextended helical nanographene with circul cAPR 0 v303 a

Helical nanographenes have garnered substantial attention owing to their finely adjustable optical and semiconducting properties. The strategic integration of both helicity and heteroatoms into the nanographene structure, facilitated by a boron-oxygen-based multiple resonance (MR) thermally activated delayed fluorescence (TADF), elevates its photophysical and chiroptical features. This signifies the introduction of an elegant category of helical nanographene that combines optical (TADF) and chiroptical (CPL) features. In this direction, we report the synthesis, optical, and chiroptical properties of boron, oxygen-doped pi-extended helical nanographene. The pi-extension induces distortion in the DOBNA-incorporated nanographene, endowing a pair of helicenes, (P)-B2NG, and (M)-B2NG exhibiting circularly polarized luminescence with glum of -2.3x10-3 and +2.5x10-3, respectively. B2NG exhibited MR-TADF with a lifetime below 5 mu s, and a reasonably high fluorescence quantum yield (50 %). Our molecular design enriches the optical and chiroptical properties of nanographenes and opens up new opportunities in multidisciplinary fields. B, O-doped pi-extended helical nanographene has been explored for its optical and chiroptical properties. The presence of helical and nanographene segments stabilize the helicity and imparts tunable optical properties. Helical nanographene display circularly polarized thermally activated delayed fluorescence. image

10acircularly polarized luminescence10aDOBNA10adual emission10ananographene10aTADF1 aVenugopal, Geethu1 aKumar, Viksit1 aJadhav, Ashok, Badrinaray1 aDongre, Sangram, D.1 aKhan, Abujunaid1 aGonnade, Rajesh1 aKumar, Jatish1 aBabu, Sukumaran, Santhosh uhttp://library.ncl.res.in/content/boron-and-oxygen-doped-%CF%80-extended-helical-nanographene-circularly-polarised-thermally02406nas a2200313 4500008004100000245008500041210007000126260000800196300001500204490000700219520144500226653001401671653000801685653001401693653001701707653002001724653000901744100001801753700002201771700003001793700002401823700002001847700001801867700001901885700001901904700002101923700003001944856011801974 2025 eng d00aRegioisomeric π-extended nanographene with long-lived phosphorescence afterglow0 aRegioisomeric πextended nanographene with longlived phosphoresce cFEB ae2024221250 v643 a

The cutouts of graphene sheets, particularly those with a nonplanar topology, present vast opportunities for advancement. Even a slight deviation from the planar structure can lead to intriguing (chiro)optical features for helically twisted nanographenes. In this context, we introduce two regioisomeric pi-extended nanographenes that exhibit distinct excited-state characteristics. The helicene structure and the photophysical features can be easily tuned by changing the connecting position of the nanographene to the carbazole core (2,7- and 3,6-). Single-crystal X-ray diffraction analysis confirmed the formation of nanographenes with bent and helical conformations. Both derivatives exhibited thermally activated delayed fluorescence at room temperature and phosphorescence at low temperatures. Notably, the nanographene with the bent structure displayed an impressive red afterglow lasting over 30seconds, in contrast to the very weak afterglow observed in the helical structure. DFT calculations revealed the existence of an isoenergetic higher triplet state (T-8) and comparatively weak spin-orbit coupling (T-1-S-0), thereby enabling the bent nanographene to exhibit a long-lived component and strong afterglow. Our findings highlight the significance of regioisomeric nanographenes with exceptional optical properties and offer a deeper understanding of the structure-property relationship in nonplanar nanographenes.

10aAfterglow10aCPL10aHelicenes10ananographene10aPhosphorescence10aTADF1 aKumar, Viksit1 aVenugopal, Geethu1 aJadhav, Ashok, Badrinaray1 aDongre, Sangram, D.1 aGonnade, Rajesh1 aKumar, Jatish1 aRuer, Paul, C.1 aHupp, Benjamin1 aSteffen, Andreas1 aBabu, Sukumaran, Santhosh uhttp://library.ncl.res.in/content/regioisomeric-%CF%80-extended-nanographene-long-lived-phosphorescence-afterglow