A5058737282- Luminescence and Fluorescent Materials
- Organic Light-Emitting Diodes Research
- Organic Electronics and Photovoltaics
- Advanced Semiconductor Detectors and Materials
- Chalcogenide Semiconductor Thin Films
- Semiconductor Quantum Structures and Devices
- X-ray Diffraction in Crystallography
- Molecular Junctions and Nanostructures
- Molecular Sensors and Ion Detection
- Crystallography and molecular interactions
- Crystallization and Solubility Studies
- Quantum Dots Synthesis And Properties
- Photochromic and Fluorescence Chemistry
- Advanced biosensing and bioanalysis techniques
- Synthesis and Characterization of Heterocyclic Compounds
- Photochemistry and Electron Transfer Studies
- Supramolecular Chemistry and Complexes
- Multiferroics and related materials
- Ferroelectric and Piezoelectric Materials
- Optical and Acousto-Optic Technologies
- Rare-earth and actinide compounds
- Spectroscopy and Laser Applications
- Thermal properties of materials
- Radical Photochemical Reactions
- Glass properties and applications
Solid State Physics Laboratory
1994-2024
University of St Andrews
2019-2024
Indian Institute of Science Bangalore
2012-2024
University of Delhi
1988-2024
Université Libre de Bruxelles
2023-2024
A novel fluoranthene based fluorescent chemosensor for the detection of picric acid (PA) at parts per billion (ppb) level was evaluated. Static fluorescence quenching dominant process by intercalative π–π interaction between (S1) and nitroaromatics.
Commonly, thermally activated delayed fluorescence (TADF) emitters present a twisted donor–acceptor structure. Here, electronic communication is mediated through-bond via π-conjugation between donor and acceptor groups. A second class of TADF are those where moieties through-space. In these through-space charge-transfer (TSCT) architectures, the groups disposed in pseudocofacial orientation linked bridging group that typically an arene (or heteroarene). most systems, there no direct evidence...
A series of fluoranthene derivatives (F1–F5) varied with nature and type substituents were synthesized via Diels–Alder reaction followed by in situ decarbonylation. The solid state structures have been established through single crystal X-ray diffraction (XRD). presence extended conjugation having two alkyloxy chains on phenyl rings induces flexibility to orient opposite each other interacts another unit weak π–π interactions show unique supramolecular arrangements. envisaged photophysical...
Abstract Herein we report a novel fluoranthene‐based fluorescent fluorophore 7,10‐bis(4‐bromophenyl)‐8,9‐bis[4‐(hexyloxy)phenyl]fluoranthene ( S 3 ) and its remarkable properties in applications of explosive detection. The sensitivity towards the detection nitroaromatics (NACs) was evaluated through fluorescence quenching solution, vapor, contact mode approaches. approach using thin‐layer silica chromatograp‐ hic plates exhibited femtogram (1.15 fg cm −2 limit for trinitrotoluene (TNT)...
In this study, we explore the impact of halogen functionalization on photophysical properties commonly used organic light-emitting diode (OLED) host material, 1,3-bis(N-carbazolyl)benzene (mCP). Derivatives with different numbers and types substituents mCP were synthesized. By measuring steady-state transient photoluminescence at 6 K, study type, number, position halogens intersystem crossing phosphorescence rates compounds. particular, 5 bromine atoms results in a significant increase rate...
We have successfully developed blue-emitting thermally activated delayed fluorescence (TADF) compounds derived from 2CzPN. They display novel electrochemiluminescence properties, these revealing correlations with measured Δ E ST values.
In this study, we report synthesis of symmetrically and non-symmetrically functionalized fluoranthene-based blue fluorescent molecular materials for non-doped electroluminescent devices.
The electrochemistry, electrochemiluminescence (ECL), and chemiluminescence (CL) properties of a thermally activated delayed fluorescence (TADF) emitter 4,4'-(1,2-dihydroacenaphthylene-5,6-diyl)bis(N,N-diphenylaniline) (TPA-ace-TRZ) three its analogues were investigated. TPA-ace-TRZ exhibits both (a) onset ECL (b) long-persistent luminescence, which we have attributed to the formation an aggregate excited state in excimer or exciplex form. evidence this was consistent across annihilation...
The design and synthesis is reported of 7-(9H-carbazol-9-yl)-4-methylcoumarin (Cz-Cm), comprising a carbazole donor moiety 4-methylcoumarin acceptor unit, for use in blue organic light-emitting diode. A detailed solid state, theoretical spectroscopic study was performed to understand the structure-property relationships. material exhibits deep-blue emission high photoluminescence quantum yield both solution doped matrix. electroluminescence at 430 nm, maximum brightness 292 cd m-2 an...
Herein we report the synthesis, characterization, and potential application of bis(4-(7,9,10-triphenylfluoranthen-8-yl)phenyl)sulfone (TPFDPSO2) 2,8-bis(7,9,10-triphenylfluoranthen-8-yl)dibenzo[b,d]thiophene 5,5-dioxide (TPFDBTO2) as electron transport well light-emitting materials. These fluoranthene derivatives were synthesized by oxidation their corresponding parent sulfide compounds, which prepared via Diels–Alder reaction. materials exhibit deep blue fluorescence emission in both...
Thiophene, a key building block for the construction of conjugated materials, has been scarcely studied in halogen bonding (XB)-driven self-assemblies. In present study, two thiophene derivatives modified at position 3 were (co-)crystallized using complementary XB donor/acceptor functional groups. Single-crystal X-ray diffraction analysis confirmed presence and chalcogen acting, most cases, concomitantly. While majority structures are governed by conventional N···I motif, additional S···N...
Fluoranthene-based thermally stable electron transport materials for organic light-emitting diodes were synthesized and their performance in devices was investigated.
Abstract Three D‐π‐A type linearly‐extended emitters, based on diphenylamine ( DPA ) as the donor and 2,4,6‐triphenyl‐1,3,5‐triazine TRZ acceptor, were synthesized their optoelectronic properties characterized. The introduction of an additional phenyl or phenylethynyl π‐spacer results in enhancement molar extinction coefficient a systematic bathochromic shift charge‐transfer transition absorption spectra. A mirrored photoluminescence spectra is also observed with increasing conjugation...
Abstract Zinc telluride (ZnTe) epitaxial layers were grown on gallium arsenide (GaAs) (211) substrate at different growth temperatures by molecular beam epitaxy. The fabricated interdigitated metal semiconductor configuration-based photodetector (PD) ZnTe exhibited a stable and excellent photo response in broad spectral range (250–550 nm) up to 125 °C. room temperature higher (125 °C) values of maximum current, responsivity detectivity an applied bias 5 V 550 nm wavelength 3.5 × 10 −8 A, 0.1...
Single-walled boron nitride nanotubes (BNNTs) have been explored for various applications, ranging from water desalination to osmotic power harvesting. However, no simulation work so far has modeled the changes in partial charge distribution when a flat sheet is rolled into tube, hindering ability perform accurate molecular dynamics (MD) simulations of flow through BNNTs. To address this knowledge gap, we employ electronic density functional theory (DFT) calculations precisely estimate...
Thermal evaporation from an alloyed SnTe0.32Se0.68 source forms thin film with mixed Te and SnSe constituent phases due to incongruent evaporation. The crystallites in hexagonal phase are identified by (1 0 0), 1) 1 0) diffraction planes orthorhombic as evidenced (4 (5 1), 2) (3 2 diffractions. increase the substrate temperature (T s) upto 353 K thereafter decrease disappear at 553 K. reduction disappearance of attributed thermal dissociation re-evaporation phase. T s led nearly nonexistent...