01529nas a2200205 4500008004100000022001400041245005600055210005600111260010500167300001200272490000700284520083400291653001301125653002001138653001701158100002201175700002001197700002001217856008601237 2014 eng d a2083-133100aCVD synthesis of graphene nanoplates on MgO support0 aCVD synthesis of graphene nanoplates on MgO support aWYBRZEZE WYSPIANSKIEGO 27, 50-370 WROCLAW, POLANDbOFICYNA WYDAWNICZA POLITECHNIKI WROCLAWSKIEJcJUN a243-2460 v323 a

Synthesis of graphene directly on MgO has been carried out and the structural properties of the obtained material have been investigated. Few-layered graphene was produced by simple thermal decomposition of methane over MgO powder at 950 A degrees C in a CVD reactor. The samples were purified by 10 N HNO3 treatment, and studied by TEM, Raman spectroscopy, EDAX and SEM. TEM clearly indicated the formation of graphene. EDAX showed that the purified sample contained only carbon and no traces of MgO. The characteristic Raman features of graphene were also seen as D-band at 1316 cm(-1), G-band at 1602 cm(-1), and a small 2D-band at 2700 cm(-1) in the Raman spectra. The strong D-band suggests that the graphene possess large number of boundary defects. The small 2D-band indicates the formation of few-layered graphene.

10agraphene10amagnesium oxide10ananographene1 aJugade, Ravin, M.1 aSharma, Shalini1 aGokhale, Suresh uhttp://library.ncl.res.in/content/cvd-synthesis-graphene-nanoplates-mgo-support-002617nas a2200253 4500008004100000022001400041245008400055210007000139260000800209490000700217520178600224653001202010653001302022653001902035653001702054653003102071100001802102700002502120700002402145700002002169700003002189700003002219856011402249 2023 eng d a1433-785100aIsomer effect on energy storage of π-extended S-shaped double[6]heterohelicene0 aIsomer effect on energy storage of πextended Sshaped double6hete cNOV0 v623 a

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

10aBattery10agraphene10aLi-ion battery10ananographene10aOrganic Electrode Material1 aKumar, Viksit1 aBharathkumar, H., J.1 aDongre, Sangram, D.1 aGonnade, Rajesh1 aKrishnamoorthy, Kothandam1 aBabu, Sukumaran, Santhosh uhttp://library.ncl.res.in/content/isomer-effect-energy-storage-%CF%80-extended-s-shaped-double6heterohelicene02426nas 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-thermally