@article {46831, title = {Dual mode selective detection and differentiation of TNT from other nitroaromatic compounds}, journal = {Journal of Materials Chemistry A}, volume = {8}, year = {2020}, month = {JUN }, pages = {10767-10771}, type = {Article}, abstract = {

Selective detection of explosives, especially TNT, is a highly desirable area of research and various explosives detection devices including fluorescent sensors are already in place. However, multi-mode sensors will be more useful and reliable than conventional fluorescent {\textquoteleft}{\textquoteleft}Turn Off{\textquoteright}{\textquoteright} sensors. One of the challenges is the development of selective sensors to prevent illegal transport of commonly used explosive TNT through on-the-spot analysis. In this context, we report a fluorescent polymer-based selective detection of TNT using both fluorometric and colorimetric signals. In addition, colorimetric differentiation of TNT from other nitroaromatic compounds is made possible by complexing with various amines. Even though many other sensors are available for TNT, the current demonstration is unique in terms of selectivity, sensitivity, reliability, portability, and rapidity of results. The as-developed explosive detection kit can be useful in both civilian and military operations to trace the illegal transport of TNT as well as for post-explosion analysis.

}, issn = {2050-7488}, doi = {10.1039/d0ta02091e}, author = {Patil, Goudappagouda and Dongre, Sangram D. and Das, Tamal and Babu, Sukumaran Santhosh} } @article {48939, title = {Isomer effect on energy storage of π-extended S-shaped double[6]heterohelicene}, journal = { Angewandte chemie-international edition}, volume = {62}, year = {2023}, month = {NOV}, type = {Article}, abstract = {

Recently, chiral and nonplanar cutouts of graphene have been the favorites due to their unique optical, electronic, and redox properties and high solubility compared with their planar counterparts. Despite the remarkable progress in helicenes, pi-extended heterohelicenes have not been widely explored. As an anode in a lithium-ion battery, the racemic mixture of pi-extended double heterohelical nanographene containing thienothiophene core exhibited a high lithium storage capability, attaining a specific capacity of 424 mAh g-1 at 0.1 A g-1 with excellent rate capability and superior long-term cycling performance over 6000 cycles with negligible fade. As a first report, the pi-extended helicene isomer (PP and MM), with the more interlayer distance that helps faster diffusion of ions, has exhibited a high capacity of 300 mAh g-1 at 2 A g-1 with long-term cycling performance over 1500 cycles compared to the less performing MP and PM isomer and racemic mixture (150 mAh g-1 at 2 A g-1). As supported by single-crystal X-ray analysis, a unique molecular design of nanographenes with a fixed (helical) molecular geometry, avoiding restacking of the layers, renders better performance as an anode in lithium-ion batteries. Interestingly, the recycled nanographene anode material displayed comparable performance. A pi-extended double heterohelical nanographene of thienothiophene core fused with two hexabenzocoronene units exhibits excellent performance as an anode in a lithium-ion battery. The isomer (PP and MM) with more interlayer distance exhibited a high lithium storage capability compared to the other isomer and racemic mixture. Helical nanographene anodes display excellent rate capability, superior long-term cycling performance, and recyclability.image

}, keywords = {Battery, graphene, Li-ion battery, nanographene, Organic Electrode Material}, issn = {1433-7851}, doi = {10.1002/anie.202311657}, author = {Kumar, Viksit and Bharathkumar, H. J. and Dongre, Sangram D. and Gonnade, Rajesh and Krishnamoorthy, Kothandam and Babu, Sukumaran Santhosh} } @article {48758, title = {Thermally activated delayed fluorescent solvent-free organic liquid hybrids for tunable emission applications}, journal = {Chemistry-An Asian Journal}, volume = {18}, year = {2023}, month = {JUL }, type = {Article}, abstract = {

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.

}, keywords = {3D printing, Energy Transfer, OLED, Organic Liquids, TADF}, issn = {1861-4728}, doi = {10.1002/asia.202300276}, author = {Nidhankar, Aakash D. D. and Goudappagouda and Kothavade, Premkumar D. and Dongre, Sangram D. and Veer, Sairam Dnyaneshwar and Dash, Soumya Ranjan and Rajeev, Kavya and Unni, K. N. Narayanan and Shanmuganathan, Kadhiravan and Babu, Sukumaran Santhosh} } @article {49100, title = {Boron- and oxygen-doped π-extended helical nanographene with circularly polarised thermally activated delayed fluorescence}, journal = {Chemistry-A European Journal}, volume = {30}, year = {2024}, month = {APR }, type = {Article}, abstract = {

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

}, keywords = {circularly polarized luminescence, DOBNA, dual emission, nanographene, TADF}, issn = {0947-6539}, doi = {10.1002/chem.202304169}, author = {Venugopal, Geethu and Kumar, Viksit and Jadhav, Ashok Badrinarayan and Dongre, Sangram D. and Khan, Abujunaid and Gonnade, Rajesh and Kumar, Jatish and Santhosh Babu, Sukumaran} } @article {49318, title = {Tailoring helical ends of π-extended [6]heterohelicenes to control optical, and electrochemical features}, journal = {Chemical Communications}, volume = {60}, year = {2024}, month = {OCT }, pages = {11944-11947}, type = {Article}, abstract = {

The inherent helical chirality and improved pi-stacking capabilities endow helicenes with fascinating photophysical characteristics when decorated with lateral pi-extensions. Here, we report the synthesis and physicochemical characterization of expanded hetero[6]helicenes fused with thiadiazole and selenadiazole rings at the helical ends. Comparing these heterohelicenes revealed the impact of the heteroatom-embedded aromatic rings on the excited state and redox features. A small structural variation of the terminal rings from thiadiazole to selenadiazole caused a striking change in the heterohelical nanographenes. The inherent helical chirality and improved pi-stacking capabilities endow helicenes with fascinating photophysical characteristics when decorated with heteroatoms.

}, issn = {1359-7345}, doi = {10.1039/d4cc03707c}, author = {Kumar, Viksit and Dongre, Sangram D. and Venugopal, Geethu and Narayanan, Aswini and Babu, Sukumaran Santhosh} }