02117nas a2200277 4500008004100000022001400041245011800055210006900173260000900242300001400251490000600265520115800271653001501429653001901444653001901463653002101482653001901503100002501522700002801547700002601575700003201601700002701633700002601660700002401686856012901710 2020 eng d a2574-096200aHexaaminobenzene derived two-dimensional polymer supercapacitor with high specific capacitance and energy density0 aHexaaminobenzene derived twodimensional polymer supercapacitor w cJUL  a6352-63590 v33 a

Recent research interest has been shifted toward energy storage devices, especially supercapacitors, which provide high specific power and long cycle life. In this context, two-dimensional organic polymers are a class of versatile materials found to be useful in energy storage applications. However, the performance is not promising due to the low capacitance, energy density, and cyclic stability. Here, we report a two-dimensional polymer derived from hexaaminobenzene and pyromellitic dianhydride and its excellent supercapacitor performance. The specific capacitance of the two-dimensional polymer is found to be 805 F g(-1) at 0.5 A g(-1) current density in galvanostatic charge-discharge, which is the highest among the organic twodimensional polymer and most of the carbon-based materials. The superior performance of the 2D-polymer compared to a model derivative (350 F g(-1) at 0.5 A g(-1) current density) points to the critical role of a 2D-platform to excel. The high energy density, excellent cyclic stability, and low self-discharge rate support the 2D-polymer supercapacitor as a promising candidate for futuristic applications.

10a2D-polymer10aenergy density10aEnergy storage10ahexaaminobenzene10asupercapacitor1 aWakchaure, Vivek, C.1 aKottaichamy, Alagar, R.1 aNidhankar, Aakash, D.1 aRanjeesh, Kayaramkodath, C.1 aNazrulla, Mohammed, A.1 aThotiyl, Musthafa, O.1 aBabu, Sukumaran, S. uhttps://library.ncl.res.in/content/hexaaminobenzene-derived-two-dimensional-polymer-supercapacitor-high-specific-capacitance02111nas a2200301 4500008004100000022001400041245007700055210006900132260000800201300001600209490000700225520116400232653001401396653001301410653002001423653003001443653001601473100002601489700001801515700002901533700003101562700001801593700002401611700002401635700002301659700003001682856009701712 2020 eng d a1433-785100aSelf-assembled helical arrays for the stabilization of the triplet state0 aSelfassembled helical arrays for the stabilization of the triple cJUL a13079-130850 v593 a

Room-temperature phosphorescence of metal and heavy atom-free organic molecules has emerged as an area of great potential in recent years. A rational design played a critical role in controlling the molecular ordering to impart efficient intersystem crossing and stabilize the triplet state to achieve room-temperature ultralong phosphorescence. However, in most cases, the strategies to strengthen phosphorescence efficiency have resulted in a reduced lifetime, and the available nearly degenerate singlet-triplet energy levels impart a natural competition between delayed fluorescence and phosphorescence, with the former one having the advantage. Herein, an organic helical assembly supports the exhibition of an ultralong phosphorescence lifetime. In contrary to other molecules, 3,6-phenylmethanone functionalized 9-hexylcarbazole exhibits a remarkable improvement in phosphorescence lifetime (>4.1 s) and quantum yield (11 %) owing to an efficient molecular packing in the crystal state. A right-handed helical molecular array act as a trap and exhibits triplet exciton migration to support the exceptionally longer phosphorescence lifetime.

10acarbazole10ahelicity10aphenylmethanone10aultralong phosphorescence10awaveguiding1 aNidhankar, Aakash, D.1 aGoudappagouda1 aKumari, Divya, S. Mohana1 aChaubey, Shailendra, Kumar1 aNayak, Rashmi1 aGonnade, Rajesh, G.1 aKumar, G., V. Pavan1 aKrishnan, Retheesh1 aBabu, Sukumaran, Santhosh uhttps://library.ncl.res.in/content/self-assembled-helical-arrays-stabilization-triplet-state01590nas a2200181 4500008004100000022001400041245007400055210006900129260000900198300001400207490000700221520098100228100001801209700002601227700002201253700003001275856010301305 2021 eng d a1477-052000aAggregation-induced phosphorescence of an anthraquinone based emitter0 aAggregationinduced phosphorescence of an anthraquinone based emi cFEB  a1004-10080 v193 a

Room temperature phosphorescence (RTP) of metal-free organic molecules is a hot topic of current research interest. RTP can be enhanced through aggregation, crystallization, and the support of polymers and host-guest assemblies. The characteristics of highly phosphorescent aggregates formed from conventional chromophores make them ideal candidates for many potential applications. In this direction, we focused on the aggregation-induced phosphorescence of an anthraquinone derivative AqC6 in solution and in crystal state. The weakly emissive dilute solution exhibits a tunable emission with enhanced intensity and room temperature phosphorescence by increasing the concentration and solvent-antisolvent combination. The enhanced phosphorescence of crystals has been recreated in the solution by making use of aggregation. Interestingly, the support of PMMA enabled AqC6 to achieve enhanced processability, phosphorescence lifetime (174 ms) and quantum yield (5%).

1 aGoudappagouda1 aNidhankar, Aakash, D.1 aNayak, Rashmi, A.1 aBabu, Sukumaran, Santhosh uhttps://library.ncl.res.in/content/aggregation-induced-phosphorescence-anthraquinone-based-emitter02006nas a2200181 4500008004100000022001400041245006000055210005900115260000800174300001400182490000700196520142700203100002601630700001801656700002501674700003001699856009501729 2021 eng d a2041-652000aEfficient metal-free organic room temperature phosphors0 aEfficient metalfree organic room temperature phosphors cMAR a4216-42360 v123 a

An innovative transformation of organic luminescent materials in recent years has realised the exciting research area of ultralong room-temperature phosphorescence. Here the credit for the advancements goes to the rational design of new organic phosphors. The continuous effort in the area has yielded wide varieties of metal-free organic systems capable of extending the lifetime to several seconds under ambient conditions with high quantum yield and attractive afterglow properties. The various strategies adopted in the past decade to manipulate the fate of triplet excitons suggest a bright future for this class of materials. To analyze the underlying processes in detail, we have chosen high performing organic triplet emitters that utilized the best possible ways to achieve a lifetime above one second along with impressive quantum yield and afterglow properties. Such a case study describing different classes of metal-free organic phosphors and strategies adopted for the efficient management of triplet excitons will stimulate the development of better candidates for futuristic applications. This Perspective discusses the phosphorescence features of single- and multi-component crystalline assemblies, host-guest assemblies, polymers, and polymer-based systems under various classes of molecules. The various applications of the organic phosphors, along with future perspectives, are also highlighted.

1 aNidhankar, Aakash, D.1 aGoudappagouda1 aWakchaure, Vivek, C.1 aBabu, Sukumaran, Santhosh uhttps://library.ncl.res.in/content/efficient-metal-free-organic-room-temperature-phosphors01605nas a2200229 4500008004100000022001400041245012100055210006900176260000900245300001400254490000700268520078700275100003301062700002101095700002601116700001801142700001801160700001801178700002601196700003001222856012301252 2022 eng d a1359-734500aDonor-acceptor based solvent-free organic liquid hybrids with exciplex emission and room temperature phosphorescence0 aDonoracceptor based solventfree organic liquid hybrids with exci cFEB  a1998-20010 v583 aSolvent-free organic liquids are well-known for their excellent luminescence features. Hence, the recent developments in this area have marked them as potential emitters with high quantum yield and enhanced processability. The support of an available liquid matrix enables doping to deliver hybrid liquids with intriguing luminescence features. In this direction, we report solvent-free liquid donor-acceptor pairs with exciplex emission and room temperature phosphorescence at very low acceptor loading. The underlying weak intermolecular interactions have been revealed by 2D NMR techniques and theoretical calculations. The formation of large-area thin films by exciplex and phosphorescent liquid hybrids will encourage the development of scalable lighting and display materials.1 aWakchaure, Vivek, Chandrakan1 aVeer, Sairam, D.1 aNidhankar, Aakash, D.1 aGoudappagouda1 aNayak, Rashmi1 aAsokan, Kiran1 aRavindranathan, Sapna1 aBabu, Sukumaran, Santhosh uhttps://library.ncl.res.in/content/donor-acceptor-based-solvent-free-organic-liquid-hybrids-exciplex-emission-and-room02309nas a2200313 4500008004100000022001400041245009600055210006900151260000800220300001400228490000700242520130500249653001601554653001401570653001701584653001801601653002201619653001401641100003101655700002001686700002601706700001701732700002301749700001901772700002001791700002901811700003101840856012401871 2023 eng d a0032-388800aLuminescent 3D printed poly(lactic acid) nanocomposites with enhanced mechanical properties0 aLuminescent 3D printed polylactic acid nanocomposites with enhan cJUL a2059-20720 v633 a

The three-dimensional (3D) printing of functional composite materials has gained tremendous interest in recent years. Nevertheless, research on 3D printing of luminescent composite materials is very limited, and the mechanical properties of such 3D-printed composites are poor. Herein, we report the preparation and characterization of a poly(lactic acid) (PLA) composite that, when 3D printed, exhibits enhanced toughness and high solid-state fluorescence quantum yield. Incorporation of only 1 wt% pyrene butyric acid modified cellulose nanofibers (PBA-m-CNF) and l0 wt% thermoplastic polyurethane (TPU) into PLA led to 223% increase in toughness and 21% increase in tensile modulus of PLA. Scanning electron microscopy (SEM) and X-ray microcomputed tomography (mu-CT) analysis of the fractured cross-sections of 3D printed composites revealed a ductile failure mode. The PLA/PBA-m-CNF1/TPU10 3D printed composite also exhibited a high solid-state fluorescence quantum yield of 38.35%. To the best of our knowledge, this is the first report to show both enhanced mechanical properties and high solid-state fluorescence emission for 3D printable PLA. Such functional PLA composites could have potential applications in the fabrication of complex-shaped sensors, optical light pipes, etc.

10a3D printing10aComposite10afluorescence10aNanocellulose10apoly(lactic acid)10atoughness1 aKothavade, Premkumar, Anil1 aYadav, Prashant1 aNidhankar, Aakash, D.1 aTorris, Arun1 aPol, Harshawardhan1 aKafi, Abdullah1 aBateman, Stuart1 aSukumaran, Santosh, Babu1 aShanmuganathan, Kadhiravan uhttps://library.ncl.res.in/content/luminescent-3d-printed-polylactic-acid-nanocomposites-enhanced-mechanical-properties02177nas a2200253 4500008004100000022001400041245011800055210006900173260000800242490000700250520127800257653002001535653001901555653003301574653001401607653001601621100003301637700002901670700002601699700001801725700002201743700003001765856012801795 2023 eng d a1433-785100aPolymerizable solvent-free organic liquids: a new approach for large area flexible and foldable luminescent films0 aPolymerizable solventfree organic liquids a new approach for lar cAUG0 v623 a

The high demand for light-emitting and display devices made luminescent organic materials as attractive candidates. Solvent-free organic liquids are one of the promising emitters among them due to the salient features. However, the inherent limitations of forming sticky and noncurable surfaces must be addressed to become an alternate emitter for large-area device applications. Herein, we functionalized solvent-free organic liquids having monomeric emission in bulk with polymerizable groups to improve the processability. The polymerizable group on carbazole, naphthalene monoimide, and diketopyrrolopyrrole-based solvent-free liquid emitters enabled on-surface polymerization. These emitters alone and in combinations can be directly coated on a glass substrate without the help of solvents. Subsequent photo or thermal polymerization leads to stable, non-sticky, flexible, foldable, and free-standing large-area films with reasonably high quantum yield. Our demonstration of the tunable and white light-emitting films using polymerizable solvent-free liquids might be a potential candidate in flexible/foldable/stretchable electronics. The new concept of polymerizable liquid can be extended to other functional features suitable for futuristic applications.

10aEnergy Transfer10apolymerization10aSolvent-Free Organic Liquids10aThin-Film10aWhite Light1 aWakchaure, Vivek, Chandrakan1 aVeer, Sairam, Dnyaneshwa1 aNidhankar, Aakash, D.1 aKumar, Viksit1 aNarayanan, Aswini1 aBabu, Sukumaran, Santhosh uhttps://library.ncl.res.in/content/polymerizable-solvent-free-organic-liquids-new-approach-large-area-flexible-and-foldable