02552nas a2200169 4500008004100000022001400041245012900055210006900184260011000253300001600363490000700379520179700386100001802183700002302201700003002224856012802254 2014 eng d a1463-907600aOrganic soluble and uniform film forming oligoethylene glycol substituted BODIPY small molecules with improved hole mobility0 aOrganic soluble and uniform film forming oligoethylene glycol su aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcMAY a13376-133820 v163 a

Judiciously chosen side chains of conjugated molecules have a positive impact on charge transport properties when used as the active material in organic electronic devices. Amongst the side chains, oligoethylene glycols (OEGs) have been relatively unexplored due to their hydrophilic nature. OEGs also affect the smooth film formation of conjugated molecules, which preclude device fabrication. However, X-ray diffraction studies have shown that OEGs facilitate intermolecular contact, which is a desirable property for the fabrication of organic electronic devices. Thus the challenge is to design and synthesize organic solvent soluble and uniform film forming conjugated molecules with OEG side chains. We have designed and synthesized conjugated small molecules (CSMs) comprising BODIPY as acceptor and triphenylamine as donor with an OEG side chain. This molecule forms smooth films when processed from organic solvents. In order to understand the impact of the OEG side chain, we have also synthesized alkyl chain analogs. All the molecules exhibit exactly the same HOMO and LUMO energy levels, but the packing in the solid state is different. CSM with methyl side chains exhibit an inter planar distance of 4.15 A. Contrary to this, the OEG side chain containing CSM showed an inter planar spacing of 4.30 A, which is 0.2 A less than the alkyl side chain comprising CSMs. Please note that the length of the hydrophobic and hydrophilic side chains is the same. Interestingly, the OEG side chain comprising CSM showed two orders of higher hole carrier mobilities compared to all the other derivatives. The same molecule also showed an extremely low threshold voltage of -0.27 V indicating the OEG side chains' favourable interaction between substrate as well as between molecules.

1 aSingh, Saumya1 aVenugopalan, Vijay1 aKrishnamoorthy, Kothandam uhttps://library.ncl.res.in/content/organic-soluble-and-uniform-film-forming-oligoethylene-glycol-substituted-bodipy-small-002298nas a2200241 4500008004100000245013900041210006900180260000800249300001400257490000600271520142600277653002201703653001101725653002801736653001501764653002501779653002001804100002101824700003401845700002301879700003001902856012401932 2023 eng d00aOrganic field effect transistors comprising copolymers synthesized without structure-directing moieties with enhanced carrier mobility0 aOrganic field effect transistors comprising copolymers synthesiz cAPR a2338-23440 v53 a

Conjugated materials are synthesized by C-C bond formation reactions. Trimethyltin and boronic acid are two widely used structure-directing moieties. While using the ethynyl moiety as a part of the monomer, additional structure-directing moieties are not needed. However, ethynylene will be part of the conjugated material. Often, the polymers with an ethynylene moiety negatively impact the polymers' properties. However, the ethynylene moiety could minimize the dihedral angle if the monomer has steric functionalities. For example, BODIPY is an attractive monomer due to its high molar extinction coefficient, partial quinoidal character, and high quantum yield. However, materials based on BODIPY exhibited poor charge carrier mobility due to steric hindrance generated by four methyl groups. Herein, we copolymerize BODIPY with ethynylene comprising i-indigo and thieno-i-indigo. The copolymer with thieno-i-indigo showed increased molecular weight and significantly reduced band gap compared to the copolymer with i-indigo. The copolymer with i-indigo showed immeasurably low hole transport mobility. On the other hand, the copolymer with thieno-i-indigo exhibited 0.003 cm2V(-1) s(-1). These measurements were made using field effect transistors. We also measured the charge carrier mobility using the space charge-limited current method. Both copolymers exhibited a mobility of 10(-3) cm(2) V-1 s(-1).

10aacetylene linkage10aBODIPY10afield effect transistor10aiso-indigo10aSonogashira coupling10athienoisoindigo1 aSwain, Gitanjali1 aJavaregowda, Bharathkumar, H.1 aDambhare, Neha, V.1 aKrishnamoorthy, Kothandam uhttps://library.ncl.res.in/content/organic-field-effect-transistors-comprising-copolymers-synthesized-without-structure02195nas a2200265 4500008004100000022001400041245011700055210006900172260000800241490000700249520126700256653001201523653000801535653002401543653001801567653001401585100002901599700003401628700002901662700002001691700002601711700003001737700003001767856013201797 2026 eng d a1613-681000aOrthogonally Engineered Redox-Active Polyimide-Carbon Nanotube Hybrids for Long-Life Lithium-Ion Battery Cathode0 aOrthogonally Engineered RedoxActive PolyimideCarbon Nanotube Hyb cJAN0 v223 a

The diverse structural tunability and engineered electronic properties of organic polymers have sparked significant interest in their use as cathode materials for lithium-ion storage. Recent advances suggest that organic cathodes can serve as promising alternatives to conventional metal oxide counterparts due to their elemental abundance, safety, and high theoretical capacity. However, developing cathode materials that simultaneously exhibit high specific capacity, long cycle life, and excellent rate performance remains a critical challenge. In this study, the synthesis and application of a redox-active polyimide based on orthogonally positioned, active site-rich mellitic trianhydride (MTA) and naphthalene diimide (NDI), integrated with multi-walled carbon nanotubes (MWCNTs), referred to as MTA-NDI@CNT are reported. The pristine MTA-NDI polymer demonstrates a specific capacity of 60 mAh g-1 at a current density of 200 mA g-1 and exhibits remarkable cycling stability over 20 000 cycles. Upon hybridisation with CNT (10 wt.%), the composite (MTA-NDI@CNT) delivers a nearly threefold enhancement in specific capacity, reaching 170 mAh g-1 at 500 mA g-1, along with stable cycling performance over 1300 cycles and 60.5% capacity retention.

10acathode10aCNT10alithium-ion battery10aorthogonality10aPolyimide1 aThanasekar, Chandragopal1 aJavaregowda, Bharathkumar, H.1 aVeer, Sairam, Dnyaneshwa1 aDevasia, George1 aKrishnamurty, Sailaja1 aKrishnamoorthy, Kothandam1 aBabu, Sukumaran, Santhosh uhttps://library.ncl.res.in/content/orthogonally-engineered-redox-active-polyimide-carbon-nanotube-hybrids-long-life-lithium-ion