Here, we design and synthesize an organic laser molecule, 2,7-diphenyl-9H-fluorene (LD-1), which has state-of-the-art integrated optoelectronic properties with a high mobility of 0.25 cm2 V–1 s–1, a high photoluminescence quantum yield of 60.3%, and superior deep-blue laser characteristics (low threshold of Pth = 71 μJ cm–2 and Pth = 53 μJ cm–2 and high quality factor (Q) of ∼3100 and ∼2700 at emission peaks of 390 and 410 nm, respectively). Organic light-emitting transistors based on LD-1 are for the first time demonstrated with obvious electroluminescent emission and gate tunable features. This work opens the door for a new class of organic semiconductor laser molecules and is critical for deep-blue optical and laser applications.

Construction of high-performance organic light-emitting transistors (OLETs) remains challenging due to the limited desired organic semiconductor materials. Here, two superior high mobility emissive organic semiconductors, 2,6-diphenylanthracene (DPA) and 2,6-di(2-naphthyl) anthracene (dNaAnt), are introduced into the construction of OLETs. By optimizing the device geometry for balanced ambipolar efficient charge transport and using high-quality DPA and dNaAnt single crystals as active layers, high-efficiency single-component OLETs are successfully fabricated, with the demonstration of strong and spatially controlled light emission within both p- and n- conducting channels and output of high external quantum efficiency (EQE). The obtained EQE values in current devices are approaching 1.61% for DPA-OLETs and 1.75% for dNaAnt-based OLETs, respectively, which are the highest EQE values for single-component OLETs in the common device configuration reported so far. Moreover, high brightnesses of 1210 and 3180 cd m−2 with current densities up to 1.3 and 8.4 kA cm−2 are also achieved for DPA- and dNaAnt-based OLETs, respectively. These results demonstrate the great potential applications of high mobility emissive organic semiconductors for next-generation rapid development of high-performance single-component OLETs and their related organic integrated electro-optical devices.

Conjugated polymer (CP) films with high molecular order are attractive in polymeric optoelectronics, but challenging. Herein, we adopt a facile strategy including synergetic polymerization and self-assembly for crystalline CP films at a dynamic air/water interface. With poly(2,5-dihexyloxy-1,4-phenylenebutadiynylene) (poly-DHO-PBD) as one case shown from poly(butadiynylene) derivatives, large-area two-dimensional (2D) crystalline poly-DHO-PBD films with sizes of hundreds of micrometers and thicknesses down to tens of nanometers are successfully obtained from its 1,4-diethynyl-2,5-bis(hexyloxy)benzene (DEBHB) monomers by optimizing the interfacial Glaser-type reaction conditions, which can also be extended for the synthesis of four other poly(butadiynylene) derivatives. The high-quality crystalline CP films demonstrate efficient charge transport performance and excellent stability in electronic devices. This result opens a new avenue for preparing 2D crystalline CP films and would motivate increasing related lines of research on more complex functional CPs towards high performance polymeric optoelectronic devices and fundamental studies.

Organic semiconductors integrating excellent charge transport with efficient solid emission are very challenging to be attained in the construction of light-emitting transistors and even for realization of electrically pumped organic lasers. Herein, we introduce naphthyl units at 2,6-positions of anthracene to achieve 2,6-di(2-naphthyl)anthracene (dNaAnt), which adopts J-aggregated mode in the solid state as a balanced strategy for excellent charge transporting and efficient solid state emission. Single crystal field-effect transistors show mobility up to 12.3 cm2·V–1·s–1 and a photoluminescence quantum yield of 29.2% was obtained for dNaAnt crystals. Furthermore, organic light-emitting transistors (OLETs) based on dNaAnt single crystals distribute outstanding balanced ambipolar charge transporting property (μh = 1.10 cm2·V–1·s–1, μe = 0.87 cm2·V–1·s–1) and spatially controllable emission, which is one of the best performances for OLETs.

Molecular order and orientation significantly influence the physical properties of organic materials and their corresponding device properties. Therefore ordering organic molecules especially conjugated polymer molecules in the active layer has been a hot topic in organic electronics for high performance organic electronics and remarkable progress has been demonstrated recently. The purpose of this minireview is to highlight the novel strategies for controlling conjugated polymer molecule orders in the solid state, including rational chemical design, optimizing solution-processing techniques and growth of high quality polymer crystalline micro/nanostructures. Moreover, the charge transport mechanisms in conjugated polymers and the relationship of oriented polymer molecules with their field-effect properties are also discussed. Finally, a concise conclusion and perspective of highly ordered conjugated polymer molecules in organic electronics are also addressed.

Organic photoresponse materials and devices are critically important to organic optoelectronics and energy crises. The activities of photoresponse in organic materials can be summarized in three effects, photoconductive, photovoltaic and optical memory effects. Correspondingly, devices based on the three effects can be divided into (i) photoconductive devices such as photodetectors, photoreceptors, photoswitches and phototransistors, (ii) photovoltaic devices such as organic solar cells, and (iii) optical data storage devices. It is expected that this systematic analysis of photoresponse materials and devices could be a guide for the better understanding of structure–property relationships of organic materials and provide key clues for the fabrication of high performance organic optoelectronic devices, the integration of them in circuits and the application of them in renewable green energy strategies (critical review, 452 references).