Pixeled Electroluminescence from Multilayer Heterostructure Organic Light-Emitting Transistors

Improved performance of multilayer heterostructure organic light-emitting transistors (OLETs) was observed in brightness and external quantum efficiency (EQE) by inserting an ultrathin MoO_<i>x</i> layer and TPBI buffer layer. With in-plane emission mainly beneath the drain electrode with a maximum width of 120 μm, an EQE of 0.16% at a brightness of 238 cd/m² was obtained. Different sizes of pixeled OLETs were fabricated by restricting the pixel length by narrowing the width of the gate electrode perpendicular to the source/drain electrodes. Light emission pixels with sizes from 25 to 400 μm have been successfully demonstrated. The maximum width of the emission zone was not affected, and the maximum EQE and the corresponding brightness presented an increasing tendency for pixeled OLETs. The results in our work are helpful for developing a new generation of OLET-based display technology

A General Phase-Transfer Protocol for Mineral Acids and Its Application in the Large-Scale Synthesis of Highly Nanoporous Iron Phosphate in Nonaqueous Solvent

As a general protocol for transferring mineral acids from an aqueous solution to an organic phase, mineral acids are extracted with secondary carbon primary amine (C_9–11)₂CHNH₂ (commercial code: N1923) into an organic phase (e.g., heptane or benzene) because of the complexation reaction and the formation of typical reversed micelles. Based on this principle, a novel approach for a large-scale synthesis of highly nanoporous iron phosphate particles is developed via the formed RNH₃⁺/H₂PO₄^– (H₂O)/oil reversed micelle system and ethanol–Fe³⁺ solutions. Synthetic conditions, such as H₃PO₄ concentration in reversed micelles and Fe³⁺ concentration in ethanol–Fe³⁺ solution are investigated and optimized. The product is characterized using transmission electron microscopy, Brunauer–Emett–Teller, thermogravimetric analysis, X-ray diffraction, and Fourier transform infrared spectroscopy. The as-obtained iron phosphate is flocculent and highly porous, exhibiting a high reported surface area of 144 m²/g. The synthetic procedure is relatively simple and is suitable for large-scale fabrication, and the used organic amines can be recycled. The power of this approach is demonstrated using other kinds of organic amines, such as tri-n-octylamine (TOA) and tri-C_8–10-alkylmethyl ammonium chloride (N263), as phase-transfer reagents exhibiting promising application in the synthesis of highly nanoporous materials

Harvesting Triplet Excitons with Exciplex Thermally Activated Delayed Fluorescence Emitters toward High Performance Heterostructured Organic Light-Emitting Field Effect Transistors

The utilization of triplet excitons plays a key role in obtaining high emission efficiency for organic electroluminescent devices. However, to date, only phosphorescent materials have been implemented to harvest the triplet excitons in the organic light-emitting field effect transistors (OLEFETs). In this work, we report the first incorporation of exciplex thermally activated delayed fluorescence (TADF) emitters in heterostructured OLEFETs to harvest the triplet excitons. By developing a new kind of exciplex TADF emitter constituted by m-MTDATA (4,4′,4″-tris­(<i>N</i>-3-methylphenyl-<i>N</i>-phenylamino)­triphenylamine) as the donor and OXD-7 (1,3-bis­[2-(4-<i>tert</i>-butylphenyl)-1,3,4-oxadiazo-5-yl]­benzene) as the acceptor, an exciton utilization efficiency of 74.3% for the devices was achieved. It is found that the injection barrier between hole transport layer and emission layer as well as the ratio between donor and acceptor would influence the external quantum efficiency (EQE) significantly. Devices with a maximum EQE of 3.76% which is far exceeding the reported results for devices with conventional fluorescent emitters were successfully demonstrated. Moreover, the EQE at high brightness even outperformed the result for organic light-emitting diode based on the same emitter. Our results demonstrate that the exciplex TADF emitters can be promising candidates to develop OLEFETs with high performance

Improved Performance of Organic Light-Emitting Field-Effect Transistors by Interfacial Modification of Hole-Transport Layer/Emission Layer: Incorporating Organic Heterojunctions

Organic heterojunctions (OHJs) consisting of a strong electron acceptor 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile (HAT-CN) and an electron donor N,N′-di­(naphthalene-1-yl)-N,N′-diphenyl-benzidine (NPB) were demonstrated for the first time that they can be implemented as effective modification layers between hole transport layer (HTL) and emission layer in the heterostructured organic light-emitting field effect transistors (OLEFETs). The influence of both HAT-CN/NPB junction (npJ) and NPB/HAT-CN junction (pnJ) on the optoelectronic performance of OLEFETs were conscientiously investigated. It is found that both the transport ability of holes and the injection ability of holes into emissive layer can be dramatically improved via the charge transfer of the OHJs and that between HAT-CN and the HTL. Consequently, OLEFETs with pnJ present optimal performance of an external quantum efficiency (EQE) of 3.3% at brightness of 2630 cdm^–2 and the ones with npJs show an EQE of 4.7% at brightness of 4620 cdm^–2. By further utilizing npn OHJs of HAT-CN/NPB/HAT-CN, superior optoelectronic performance with an EQE of 4.7% at brightness of 8350 cdm^–2 and on/off ratio of 1 × 10⁵ is obtained. The results demonstrate the great practicality of implementing OHJs as effective modification layers in heterostructured OLEFETs

Comparison of the Genome-Wide DNA Methylation Profiles between Fast-Growing and Slow-Growing Broilers

<div><p>Introduction</p><p>Growth traits are important in poultry production, however, little is known for its regulatory mechanism at epigenetic level. Therefore, in this study, we aim to compare DNA methylation profiles between fast- and slow-growing broilers in order to identify candidate genes for chicken growth. Methylated DNA immunoprecipitation-sequencing (MeDIP-seq) was used to investigate the genome-wide DNA methylation pattern in high and low tails of Recessive White Rock (WRR_h; WRR_l) and that of Xinhua Chickens (XH_h; XH_l) at 7 weeks of age. The results showed that the average methylation density was the lowest in CGIs followed by promoters. Within the gene body, the methylation density of introns was higher than that of UTRs and exons. Moreover, different methylation levels were observed in different repeat types with the highest in LINE/CR1. Methylated CGIs were prominently distributed in the intergenic regions and were enriched in the size ranging 200–300 bp. In total 13,294 methylated genes were found in four samples, including 4,085 differentially methylated genes of WRR_h Vs. WRR_l, 5,599 of XH_h Vs. XH_l, 4,204 of WRR_h Vs. XH_h, as well as 7,301 of WRR_l Vs. XH_l. Moreover, 132 differentially methylated genes related to growth and metabolism were observed in both inner contrasts (WRR_h Vs. WRR_l and XH_h Vs. XH_l), whereas 129 differentially methylated genes related to growth and metabolism were found in both across-breed contrasts (WRR_h Vs. XH_h and WRR_l Vs. XH_l). Further analysis showed that overall 75 genes exhibited altered DNA methylation in all four contrasts, which included some well-known growth factors of IGF1R, FGF12, FGF14, FGF18, FGFR2, and FGFR3. In addition, we validate the MeDIP-seq results by bisulfite sequencing in some regions.</p> <p>Conclusions</p><p>This study revealed the global DNA methylation pattern of chicken muscle, and identified candidate genes that potentially regulate muscle development at 7 weeks of age at methylation level.</p> </div

KEGG pathways in which the common differentially methylated genes of WRR_h Vs. XH_h and WRR_l Vs. XH_l enriched.

1<p>KEGG pathway enrichments were performed with the DAVID Functional Annotation Tool (<a href="http://david.abcc.ncifcrf.gov/" target="_blank">http://david.abcc.ncifcrf.gov/</a>) and Benjiamini adjusted p<0.05 was regarded as enriched.</p

Data generated by MeDIP-seq.

1<p>WRR_h, WRR_l, XH_h, and XH_l indicated the group of Recessive White Rock with high body weight, Recessive White Rock with low body weight, Xinhua Chickens with high body weight, and Xinhua Chickens with low body weight, respectively.</p

Differentially methylated genes unique or shared among four contrasts of WRR_h Vs. WRR_l, XH_h Vs. XH_l, WRR_h Vs. XH_h, and WRR_l Vs. XH_l.

<p>The number of differently methylated genes in each comparison was given at the top of each section of figures. WRR_h Vs. WRR_l indicated the comparison between the two-tail samples of Recessive White Rock. XH_h Vs. XH_l indicated the comparison between the two-tail samples of Xinhua Chickens. WRR_h Vs. XH_h indicated the comparison between the groups of Recessive White Rock and Xinhua Chickens with high body weight. WRR_l Vs. XH_l indicated the comparison between the groups of Recessive White Rock and Xinhua Chickens with low body weight.</p

Functional classification of the whole methylated genes.

<p>(A) GO: Biological process. (B) Cellular component. (C) GO: Molecular function.</p

Methylated genes among four groups of WRR_h, WRR_l, XH_h, and XH_l.

<p>The methylated gene number was given at the top of each figure section. WRR_h, WRR_l, XH_h, and XH_l indicated the group of Recessive White Rock with high body weight, Recessive White Rock with low body weight, Xinhua Chickens with high body weight, and Xinhua Chickens with low body weight, respectively.</p