Functional Organic Materials for Optoelectronic Applications
Guest Editors Graeme Cooke, Ivana Evans and Peter Skabara introduce this themed collection on functional organic materials for optoelectronic applications, in celebration of Professor Martin Bryce’s contributions to this field.
Strategic modification of ligands for remarkable piezochromic luminescence (PCL) based on a neutral Ir(III) phosphor
A neutral Ir(III) complex has been synthesized by introducing a carboxyl group and fluorine substituents into the ligands to construct a new piezochromic luminescence (PCL) active material.
Revealing resonance effects and intramolecular dipole interactions in the positional isomers of benzonitrile-core thermally activated delayed fluorescence materials
Rather than donor–acceptor dihedral angles, the TADF performance of DMAC–BZN positional isomers is instead controlled by differences in acceptor strength arising from π-system electron density – along with a through-space dipole interaction.
Beyond efficiency: phenothiazine, a new commercially viable substituent for hole transport materials in perovskite solar cells
For the first time in perovskite solar cells, phenothiazine has been introduced as a low cost substituent to replace the commonly-used dimethoxydiphenylamine, which constitutes almost 90% of the final cost of hole transport materials.
Tailoring exciton diffusion and domain size in photovoltaic small molecules by annealing
Annealing is shown to increase both exciton diffusion and domain size in two organic photovoltaic materials. This enables both efficient light harvesting and efficient charge extraction.
The influence of molecular geometry on the efficiency of thermally activated delayed fluorescence
We report a strategy for positively influencing the conformation of thermally activated delayed fluorescence (TADF) molecules containing phenothiazine and dibenzothiophene-S,S-dioxide units.
Enhanced thermally activated delayed fluorescence through bridge modification in sulfone-based emitters employed in deep blue organic light-emitting diodes
Two thermally activated delayed fluorescence (TADF) emitters bearing a new dipyridylsulfone core as the electron-accepting unit and di-tert-butyl carbazoles as electron-donating units are reported.
Saddle-like, π-conjugated, cyclooctatetrathiophene-based, hole-transporting material for perovskite solar cells
A new HTM incorporating a saddle-like, thiophene-rich core endowed with four triphenylamine units is proposed. The new HTM leads to PSCs reaching efficiencies up to 16.3%.
Assembly effect on the charge carrier mobility in quaterthiophene-based n/p-materials
Effect of the peptide-based quaterthiophene self-assembly process on the charge mobility properties of the n/p-materials formed is studied.
Minimizing geminate recombination losses in small-molecule-based organic solar cells
Geminate recombination rates are successfully predicted for series of small-molecule bulk heterojunction solar cells applying the Marcus–Levich–Jortner equation.
A versatile star-shaped organic semiconductor based on benzodithiophene and diketopyrrolopyrrole
A novel star-shaped π-conjugated oligomer containing a benzodithiophene core and four diketopyrrolopyrrole arms is reported.
New routes to organometallic molecular junctions via a simple thermal processing protocol
Gold nanoparticle capped organometallic molecular junctions are prepared from a single source precursor by simple self-assembly and mild thermolysis.
Thermally activated delayed fluorescence vs. room temperature phosphorescence by conformation control of organic single molecules
The time-resolved photophysical analysis of a multi-color-changing mechanochromic luminescent compound has been disclosed, which reveals distinct different emission paths to boost TADF and RTP of the emitter depending on its molecular conformations.
Naphthyridine-based emitters simultaneously exhibiting thermally activated delayed fluorescence and aggregation-induced emission for highly efficient non-doped fluorescent OLEDs
Two naphthyridine-based emitters are demonstrated to be TADF and AIE emitters to afford superior EL efficiencies in non-doped OLEDs.
Homoleptic platinum(II) complexes with pyridyltriazole ligands: excimer-forming phosphorescent emitters for solution-processed OLEDs
Two new homoleptic platinum(II) complexes are reported that feature aryl-appended 5-(2-pyridyl)-1,2,4-triazole chelates acting as N^N− ligating ions, PtL12 and PtL22. They have been used to prepare high-efficiency OLEDs, in which unimolecular and bimolecular excited states contribute green and red emission respectively.
Tetrathiafulvalene–oligofluorene star-shaped systems: new semiconductor materials for fluorescent moisture indicators
Increased emission through the oxidation of tetrathiafulvalene redox-active centres in star-shaped oligofluorene structures.
Single-molecule conductance oscillations in alkane rings
We investigate the single-molecule electrical conductance of alkane rings connected to gold electrodes and demonstrate that their logarithmic conductances are ocillatory functions of length.
Almost complete radiationless energy transfer from excited triplet state of a dim phosphor to a covalently linked adjacent fluorescent dye in purely organic tandem luminophores doped into PVA matrix
Efficient harvesting of energy of the triplet exited state of dim organic phosphors by conjugated fluorophores is a general phenomenon that would be applicable for construction of novel photoluminescence-based sensors and organic light emitting devices.
Capturing the interplay between spin–orbit coupling and non-Condon effects on the photoabsorption spectra of Ru and Os dyes
A theoretical protocol developed to study the low-energy tail of the absorption spectrum of homoleptic biscyclometalated ruthenium and osmium complexes.
Air stable high-spin blatter diradicals: non-Kekulé versus Kekulé structures
1,2,4-Benzotriazinyl based stable diradicals possess singlet ground states and small singlet–triplet energy gaps with a thermal accessible triplet excited state.
Exploiting synergy between ligand design and counterion interactions to boost room temperature phosphorescence from Cu(I) compounds
Turn it up! Inter-ion interactions and ligand design can synergistically boost emission from Cu(I) complexes, tuning from orange to yellow.
Tuning the electronic properties and the planarity degree in the π-extended TTF series: the prominent role of heteroatoms
A combined experimental and theoretical study demonstrates the critical role of intramolecular S⋯S interactions in dictating the planar conformation of an extended tetrathiafulvalene.
Impact of solution temperature-dependent aggregation on the solid-state packing and electronic properties of polymers for organic photovoltaics
The impact of solution temperature-dependent aggregation of PffBT4T-2OD and PBT4T-2OD polymers on their electronic and solid-state packing properties is investigated using MD simulations and DFT calculations.
Polymorphism of derivatives of tert-butyl substituted acridan and perfluorobiphenyl as sky-blue OLED emitters exhibiting aggregation induced thermally activated delayed fluorescence
Blue multi-functional emitters with a perfluorobiphenyl moiety exhibiting polymorphism and changing emission colour.
Effects of conjugated bridges on the photovoltaic properties of ortho-functionalized perylene diimides for non-fullerene polymer solar cells
The structure of the π-bridge in an ortho-functionalized PDI plays a crucial role in controlling the active layer morphology.
About this collection
Guest Edited by Graeme Cooke, University of Glasgow, Ivana Evans, Durham University, and Peter Skabara, University of Glasgow.
This themed issue on ‘Functional Organic Materials for Optoelectronic Applications’ will showcase recent advances in experimental and/or theoretical studies of organic materials spanning the range of small molecules to polymers. The work is driven by potential applications of the materials as active components in areas such as OLEDs, organic solar cells, transistors, sensors, and charge and energy transport devices.
The themed collection will accompany the Functional Organic Materials Symposium which will be held at Durham University 12-13th September 2019, in recognition of the achievements and contributions made in this field by Professor Martin Bryce. Further details, as they become available, will be posted in the event website:http://www.dur.ac.uk/chemistry/FOM2019/