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 π-extended nanographenes that exhibit distinct excited-state characteristics.
View Article and Find Full Text PDFThermoplastic polyimides (TPIs) are promising lightweight materials for replacing metal components in aerospace, rocketry, and automotive industries. Key TPI attributes include low density, thermal stability, mechanical strength, inherent flame retardancy, and intrinsic fluorescence under UV light. The application of advanced manufacturing techniques, especially 3D printing, could significantly broaden the use of TPIs; however, challenges in melt-processing this class of polymer represent a barrier.
View Article and Find Full Text PDFThe inherent helical chirality and improved π-stacking capabilities endow helicenes with fascinating photophysical characteristics when decorated with lateral π-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.
View Article and Find Full Text PDFConspectusThe invention of solvent-free organic liquids (SOLs) was serendipitous. However, the curiosity-driven research in the later stage delivered new soft materials with exciting optical, and optoelectronic properties along with appealing physical characteristics suitable for the futuristic applications. A slight change in the molecular design resulted in a drastic change in the physical state of molecules demonstrating monomer-like features in the bulk.
View Article and Find Full Text PDFRecently, 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, π-extended heterohelicenes have not been widely explored. As an anode in a lithium-ion battery, the racemic mixture of π-extended double heterohelical nanographene containing thienothiophene core exhibited a high lithium storage capability, attaining a specific capacity of 424 mAh g at 0.
View Article and Find Full Text PDFThe 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.
View Article and Find Full Text PDFSolvent-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.
View Article and Find Full Text PDFAn 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.
View Article and Find Full Text PDFRoom-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.
View Article and Find Full Text PDFBoron-embedded aromatic hydrocarbons are a class of molecules known for their distinct electronic and/or optoelectronic properties and are thus suitable for many potential applications. Among those, boronic ester and acid containing molecules have been widely used for sensing and molecular recognition applications, respectively. We compared the sensing and molecular recognition properties of two boron-containing pyrene derivatives for fluoride and glucose sensing applications.
View Article and Find Full Text PDFProton-exchange membrane fuel cells are promising energy devices for a sustainable future due to green features, high power density, and mild operating conditions. A facile proton-conducting membrane plays a pivotal role to boost the efficiency of fuel cells, and hence focused research in this area is highly desirable. Major issues associated with the successful example of Nafion resulted in the search for alternate proton conducting materials.
View Article and Find Full Text PDFCharge-transfer complexes have been an inspiration to develop many functional soft materials. However, most of those studies have focused on solution based assemblies wherein the explicit control of solvents and their polarity are crucial. In this context, we explore an efficient and stable charge transfer liquid using a solvent-free liquid dialkoxynaphthalene donor and a naphthalenediimide acceptor.
View Article and Find Full Text PDFCorrection for 'Conducting nanofibres of solvatofluorochromic cyclohexanetrione-dithiolylidene-based C3 symmetric molecule' by Kilingaru I. Shivakumar et al., Chem.
View Article and Find Full Text PDFCorrection for 'Cascade energy transfer and tunable emission from nanosheet hybrids: locating acceptor molecules through chiral doping' by Goudappagouda et al., Chem. Commun.
View Article and Find Full Text PDFEfficient water splitting photocatalysts are an energetically demanding and cost-effective method for generating renewable energy. Significant research has been reported to advance this approach. However, the use of organic photocatalysts and the presence of residual catalysts trapped in the porous frameworks present major concerns about the efficiency of this strategy.
View Article and Find Full Text PDFOrganic phosphors have been widely explored with an understanding that crystalline molecular ordering is a requisite for enhanced intersystem crossing. In this context, we explored the room-temperature phosphorescence features of a solvent-free organic liquid phosphor in air. While alkyl chain substitution varied the physical states of the bromonaphthalimides, the phosphorescence remained unaltered for the solvent-free liquid in air.
View Article and Find Full Text PDFStimuli responsive tunable luminescence is a promising field of research. Even though mechanofluorescence is widely studied, mechanophosphorescence remains unexplored. Here we report the mechano-driven fluorescence and phosphorescence variations of a pyrene tetraboronic ester derivative.
View Article and Find Full Text PDFOne-dimensional (1D) nanostructures of π-conjugated molecules exhibiting excellent charge carrier mobilities have attracted much interest for use in organic electronic devices. Although it is tedious to form such structures, the availability of highly delocalized electron and hole carriers in these donor (D)-acceptor (A) coassemblies realize ambipolar charge transport. Here we demonstrate the use of a simple solution casting method to create an ambipolar donor-acceptor single-crystalline assembly.
View Article and Find Full Text PDFWe report a novel set of easily tailorable C symmetric molecules with a π-extended core and adorned with different thioalkyl groups, exhibiting solvatofluorochromic and amphoteric redox behaviour. The nearly planar core exhibits intermolecular face-to-face π-stacking, SS and intramolecular SO interactions. Current-sensing atomic force microscopy studies revealed a high conductivity of ∼0.
View Article and Find Full Text PDFFerroelectric materials find extensive applications in the fabrication of compact memory devices and ultra-sensitive multifunctional detectors. Face-to-face alternate stacking of electron donors and acceptors effectuate long-range unidirectional ordering of charge-transfer (CT) dipoles, promising tunable ferroelectricity. Herein we report a new TTF-quinone system-an emerald green CT complex consisting pillar[5]quinone (P5Q) and tetrathiafulvalene (TTF).
View Article and Find Full Text PDFLight harvesting donor-acceptor assemblies are indispensable to efficiently tap photons. In an attempt to improve the light harvesting efficiency of an acceptor doped assembly, we design and synthesize a donor-acceptor-donor triad which exhibits an exceptional intramolecular energy transfer with excellent efficiency. Moreover, a facile cascade energy transfer (energy funnelling) is observed in the presence of a series of second acceptors (63-91% efficiency) with tunable emission colours.
View Article and Find Full Text PDFThe helical handedness in achiral self-assemblies is mostly complex due to spontaneous symmetry breaking or kinetically controlled random assembly formation. Here an attempt has been made to address this issue through chiral anion exchange. A new class of cationic achiral C3-symmetric gelator devoid of any conventional gelation assisting functional units is found to form both right- and left-handed helical structures.
View Article and Find Full Text PDFCharge transport features of organic semiconductor assemblies are of paramount importance. However, large-area extended supramolecular structures of donor-acceptor combinations with controlled self-assembly pathways are hardly accessible. In this context, as a representative example, seeded on-surface supramolecular growth of tetrathiafulvalene and tetracyano-p-quinodimethane (TTF-TCNQ) using active termini of solution-formed sheaves has been introduced to form an extended assembly.
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