Themed collection Small Molecules and Monodisperse Oligomers for Organic Electronics

Guest editors Guillermo Bazan and Martin Bryce introduce this Journal of Materials Chemistry C themed issue on small molecules and monodisperse oligomers for organic electronics.

This review presents the main class of organophosphorus compounds (triaryl phosphines, phosphazenes, phospholes, phosphetes and diphosphacyclobutanes), which have been used in electronic devices (organic light-emitting diodes (OLEDs), organic photovoltaic cells (OPV cells), dye-sensitized solar cells (DSSCs), organic field-effect transistors (OFETs), and electrochromic cells).

The preparation of various molecules taken as representative examples of some of the main classes of molecular donors for organic solar cells is discussed in order to assess the complexity and possibilities of scaling-up their synthesis.

We investigated the synergistic effect of molecular shape anisotropy and intermolecular hydrogen-bonds in the BPy derivatives on molecular orientation towards OLEDs.

Aggregation-induced emission and delayed fluorescence are observed simultaneously for the luminogens with an electron-donor and acceptor framework.

N-Annulated perylene (NP) functionalized cyclopentadithiophene dyes with different linking modes were synthesized and the peri-NP linked dye CPD-1 gave power conversion efficiency of 7.82% in Co(II)/(III) based dye-sensitized solar cells.

A new triaryl molecule based on a benzene–benzothiadiazole–benzene core has been applied in a WOLED device.

Combining a sterically bulky, electron-deficient cyclometalating C^∧N ligands with an electron rich, highly rigidified N^∧N ligand gives an iridium complex, that achieves extraordinarily bright blue emission (Φ_PL = 90%; λ_max = 459 nm in MeCN) for a cationic iridium complex.

Copper-based LECs with a maximum efficacy of 3.0 cd A⁻¹ (luminance = 145 cd m⁻²) or with lifetimes >80 h have been achieved.

Two novel linear oligomers that can be solution-processed to form green organic light-emitting diodes (OLEDs) are reported.

The BHJ OSCs presented in this work show an energy loss of 0.53 eV but a maximum external quantum efficiency up to 61%.

A structure–property investigation of a series of cross-conjugated molecules shows that their performance is dependent on both the nature of the substituents and their conjugation axis.

Incorporating the 1,4-phenylene moiety leads to improving the photovoltaic performance.

The chrysene group, with its large band gap and high stability, was selected as a central core structure for ultra-deep-blue emitters. The effects of different side groups on the intrinsic properties of the chrysene core were systematically investigated.

Environment plays a key role in the fine tuning of the energy levels of the charge transfer state with respect to the local donor or acceptor triplet state, which can be used to control the ΔE_ST in TADF molecules.

The thin-film transistors for compounds 1–3 show typical p-type performance with mobilities of 0.012, 0.05 and 0.0055 cm² V⁻¹ s⁻¹ and on/off current ratios of 3 × 10⁵, 1 × 10⁶ and 1 × 10⁴, respectively.

The varied topography of intermolecular electronic coupling offers a wide-ranging materials design landscape to engineer solid-state molecular packing for new generations of organic semiconductors.

A new class of A–D–A molecular donor materials based on planar S,N-heterohexacenes is developed for vacuum-processed planar and bulk-heterojunction solar cells providing promising power conversion efficiencies up to 7.1%.

A series of monodisperse macromolecules based on benzodithiophene and diketopyrrolopyrrole were designed, theoretically calculated, synthesized and compared, and they exhibited strong NIR absorption and high mobility.

Unprecedented π-linkers suitable for dye sensitized solar cells.

We address the question of charge delocalization in amorphous and crystalline fullerene solids by performing state of the art calculations encompassing force-field molecular dynamics, microelectrostatic and quantum-chemical methods.

Molecular design strategy to improve the power efficiency of blue phosphorescent organic light-emitting diodes was proposed by introducing a CN modified carbazole moiety.

Electron-donating substituents are used to fine-tune the redox properties of sky-blue cyclometalated iridium complexes and improve their electroluminescence performance.