The effects of highly luminescent alkylamine-capped semiconductor cadmium telluride quantum dots (CdTe QDs) dispersion on the optical, electrical, thermal properties and supramolecular order of a discotic liquid crystal were studied.

Past decades we have witnessed many breakthroughs in research on liquid crystals (LCs) as well as significant amplification in the application of LCs. LCs are currently attracting great attention of scientists from all over the world where various researches have been implemented on the varied facets of LCs. In this review we present some recent developments in the field of discotic liquid crystals (DLCs). A large number of DLCs from various aromatic cores have been realised. However, due to paucity of space only DLCs derived from four main aromatic cores, benzene, triphenylene, hexabenzocoronene and graphene, are covered here. An outlook on these emerging two-dimensional organic semiconductor materials with relevant scientific application background has been presented.

Organic light-emitting diodes (OLEDs) based on thermally activated delayed fluorescence emitters (TADF) in simple device structures fabricated by solution processing are strongly dependent on a suitable host molecular conformation and morphology. Herein, we report the fabrication of highly efficient yellow-red TADF-based OLEDs via solution processing in a simple, two-organic-layer device structure. The devices were fabricated at different weight concentrations of 5%, 8%, and 10% emitter in an n-/p-type mixed host matrix, and their characteristics were studied. The device performance was compared with different thickness parameters for both the emitting layer (EML) and the electron transport layer (ETL) in various solvents, including chlorobenzene, dichlorobenzene, and chloroform. By optimizing the mixed ratio of EML, yellow-red OLEDs of 2-[4 (diphenylamino)phenyl]-10,10-dioxide-9H-thioxanthen-9-one (TXO-TPA) emitter in an n-/p-type host matrix of poly(N-vinylcarbazole):1,3-Bis[2-(4-tert-butylphenyl)-1,3,4-oxadiazo-5-yl]benzene (PVK:OXD-7) as a blend for the active layer were fabricated. In the best results, the device exhibited a lower turn-on voltage at around 6 V, with an external quantum efficiency (EQE) of 18.44%, current efficiency of 36.71 cd/A, and power efficiency of 14.74 Lm/W for the 8% emitter concentration. The importance of solvent for improving the electrical properties, together with organic layer thickness and host effect for the charge carrier’s transport and device characteristics are also discussed.