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Nondoped organic light-emitting diodes (OLEDs) are of paramount importance for display and lighting applications owing to their advantages of facile fabrication and outstanding stability. However, nondoped OLEDs achieving extraordinary electroluminescence (EL) performance and low turn-on voltage (

Molecular isomeric engineering is employed to construct efficient orange-red Ir(iii) complexes for WOLEDs and understand the intrinsic structure–property relationship.

A TPE-based fluorescent porous covalent organic polymer (COP-3) was designed and synthesized. The COP-3 exhibits excellent performance in sensing Fe3+ with high anti-interference, recyclability and a low limit of detection (LOD) of 0.191 μM (10.696 ppb), which is much lower than those of the reported metal-free porous polymers.

Restricted by the energy-gap law and π-π stacking, developing highly efficient red emitting materials and corresponding organic light-emitting diodes (OLEDs) having the emission over 600 nm is a formidable challenge. Three red emitters, namely DPABz-TPA, 2DPABz-TPA, and 3DPABz-TPA, are developed bearing mono-, bis-, and tri-[2,1,3]benzothiadiazole (Bz) substituted triphenylamine (TPA) as the emissive core and bulky diphenylamine (DPA) as the steric protection units. All compounds display strong red emission with peaks at 645 nm and high efficiency up to 38%. Compared with reference molecule DPABz-TPA, both 2DPABz-TPA and 3DPABz-TPA exhibit higher radiative transition rate and thermal stability. The OLEDs based on 2DPABz-TPA and 3DPABz-TPA thus show superior EL efficiencies of the maximum current efficiency of 2.5 and 2.4 cd A−1, and external quantum efficiency of 2.9% and 3.2% compared with those of DPABz-TPA (1.9 cd A−1 and 2.1%). More importantly, the efficiency roll-off of OLED based on sterically protected 3DPABz-TPA obviously decreases owing to limited intermolecular packing. These results indicate that the strategy combined multiple donor-acceptor units and steric hindrance effect is favorable for constructing robust red emitters for efficient OLEDs.

Luminescent sensors have received extensive attention due to their fast-response and easy-operation and when integrating multifunctions in a sensor, the cost will be reduced substantially. Covalent organic polymers (COPs) as multifunctional luminescent sensor with outstanding performance are still underexplored. In this work, a typical COP named as COP-2 show preponderant performance in the detection of Fe3+, MnO4−, and TNP. COP-2 has the highly efficient ability to selectively detect Fe3+ among the other metal ions, and the limit of the detection (LOD) is 0.89 ​μM, which outperforms the reported covalent organic materials. Anion sensing shows the COP-2 has the highly anti-interference ability and recyclicity to detect MnO4−. Explosive analogs sensing demonstrates that COP-2 owns the superior ability in sensing TNP in the knockdown concentration with 0.0067 ​ppm LOD, which superior to the values in the reported literature. In addition to the above superb sensing performance, COP-2 can be utilized as a white light-emitting diode (WLED) when combined with the commercial blue emission LED and presents a Commission Internationale de l’Eclairage (CIE) coordinate of (0.31, 0.32). These results show the COP-2 not only has an appealing performance in multifunctional luminescent sensing application, but also has a possible application in white light emitting.

Fluorescence imaging in red region is of great interest in both practical applicantion and fundamental research. However, the complicated synthetic approaches and low emission efficiency of the fluorescence materials are still implement their bilolgical applications. Herein, a facile synthesis method for a red luminogen with aggregation-induced emission (AIE) is reported. The AIE probe possesses simple structure and high red brightness, favoring its applications toward in vitro and vivo imaging. This study offers an ideal architecture for the construction of red AIEgens with a simple structure.

The 16e half-sandwich complex Cp*Co(S(2)C(2)B(10)H(10))(1, Cp* = pentamethylcyclopentadienyl) reacts with N-1-naphthylpropargylamide to afford two 18e complexes (2) and (3). 2 is a 1 : 1 adduct containing a four-membered metallacycle. In 3 the alkyne is twofold inserted into one Co-S bond in a head-head mode. Reactions of 1 with 1-(2-furyl)-2-propyn-1-one and 1-ferrocenyl-2-propyn-1-one lead to two types of alkyne twofold inserted products (4)/(5) and (6)/(7), respectively. The reaction of 1 with phenylacetylene gives rise to the sole complex (8) of the same structural type as 3, 4 and 6, whereas the reaction of 1 with dimethyl acetylene dicarboxylate affords the sole 1 : 1 adduct (9). Complexes 2-9 have been characterized by IR, NMR, elemental analysis and mass spectrometry, and 3-9 have also been determined by single-crystal X-ray diffraction analysis.

The Ministries of Justice and Education have implemented adolescent substance abuse prevention programs for many years. Rates of substance abuse among high school students continue to rise in spite of such programs.This study investigates adolescents' substance abuse-related knowledge and attitudes and self-confidence to resist substance use in order to identify predictive factors of poor adolescent resistance to substance use.A cross-sectional study survey gathered data on substance abuse-related knowledge and attitudes and self-confidence to resist substance use from 243 second-year senior high school students studying at two schools in northern Taiwan.Participants were most knowledgeable about tobacco (80.2%), followed by alcohol (72.0%), ecstasy (56.0%), and marijuana (30.0%). Only 19.3% demonstrated an understanding of the harmful effects of using Ketamine. A 10-point Likert scale measured participant substance use attitudes. Alcohol was the substance participants were most willing to use (2.18 ± 3.27), followed by tobacco (0.66 ± 2.19), ecstasy (0.45 ± 1.88), Ketamine (0.43 ± 1.93), and marijuana (0.38 ± 1.83). Participants had higher awareness of the harmful effects of Ketamine (t = -2.37, p = .018), marijuana (t = -2.33, p = .021), and tobacco (t = -2.02, p = .044), with participants reporting greater self-confidence to resist using these three substances. Multiple regression analysis found the three most important factors affecting participant self-confidence to resist substance use to be gender (β= .26, p.001), knowledge about the substance (β= .15, p = .028), and attitude toward substance use (β= -.20, p.001).Level of harmful effects knowledge and attitudes toward use varied among the various substances considered in this paper. Being female, having strong knowledge about the substance, and negative attitude toward substance use correlated with higher levels of self-confidence to resist substance use. Study results will be used in ongoing research designed to establish an empirical basis for adolescent substance use prevention and research, the results of which may be used directly by school nurses and military training education nurses.