High-color-purity emissions with small af ull-width at half-maximum (FWHM) are an ongoing pursuit for highresolution displays.T hough the flourishment of narrow-band emissive materials with multi-resonance induced thermally activated delayed fluorescence (MR-TADF) in the blue region, such materials have not validated their potential in other color regions.Byamplifying the influence of skeleton and peripheral units,as eries of highly efficient green-emitting MR-TADF materials are firstly reported. Peripheral units with electrondeficit properties can significantly narrowt he energy gap for bathochromic emission without compromising the color fidelity.MR-TADF emitters with photo-luminance quantum yields of above9 0% with FWHMs of 25 nm are developed. The corresponding organic light-emitting diodes showm aximum external quantum efficiency/ power efficiency of 22.02 %/ 69.82 lm W À1 with excellent long-term stability.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

Pure green emitters are essential for realizing an ultrawide color gamut in next‐generation displays. Herein, by fusing the difficult‐to‐access aza‐aromatics onto B (boron)–N (nitrogen) skeleton, a hybridized multi‐resonance and charge transfer (HMCT) molecule AZA‐BN was successfully synthesized through an effective one‐shot multiple cyclization method. AZA‐BN shows pure green fluorescence with photoluminance quantum yield of 99.7 %. The corresponding green device exhibits a maximum external quantum efficiency and power efficiency of 28.2 % and 121.7 lm W−1, respectively, with a full width half maximum (FWHM) of merely 30 nm and Commission Internationale de l'Eclairage (CIE) coordinate y of 0.69, representing the purest green bottom‐emitting organic light‐emitting diode.

Antibacterial efficiency can be effectively improved by applying targeting antibacterial materials and strategies. Herein, the successful synthesis of uniform pH-responsive Ag nanoparticle clusters (AgNCs) is demonstrated, which can collapse and reassemble into nonuniform Ag NPs upon exposure to the acidic microenvironment of bacterial infections. This pH triggered reassembly contributes greatly to the improved antibacterial activities of AgNCs against both methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli). The minimum inhibitory concentration and minimum bactericidal concentration against MRSA are as low as 4 and 32 µg mL −1 (which are 8 and 32 µg mL −1 for E. coli), respectively. In vivo skin wound healing experiments confirm AgNCs can serve as an effective wound dressing to accelerate the healing of MRSA infection. The development of responsive AgNCs offers new materials and strategies in targeting antibacterial applications.

To achieve both fast response and structural integrity during the repeating volume changes are the most significant challenges for thermoresponsive hydrogels. In this work, AuNRs/PNIPAM composite hydrogel with fast thermal/optical response and structural integrity is facilely prepared by electrospinning and following a curing treatment. By combining the photothermal property of AuNRs and thermal-responsive effect of PNIPAM, the composite hydrogel shows fast thermal/photoresponse, high heating rate, and high structural integrity with fierce size change. When laser irradiation begins, the temperature of the film increases from room temperature to 34.5 °C in 1 s and will further increase even to 60 °C in 5 s. Both the porous structure of the hydrogel and the assemble effect of AuNRs within the PNIPAM fibers facilitate the fast responsibility. Furthermore, to take advantage of this fibrous hydrogel adequately, one novel kind of thermal/photocontrolled switch based on the composite hydrogel is prepared, which exhibits fast responsivity and high stability even under acidic or basic conditions.

fluorescence (TADF) as the sensitizers while CFDs as the final emitters, the limitation is successfully broken and this so-called TADF-sensitizing-fluorescence (TSF) strategy has been recognized as one of the most promising technologies for next-generation OLEDs, offering the possibility of ultimate-high device efficiency, low efficiency roll-off as well as tunable colors with all pure organic compounds. [4][5][6] Still, the performance of TSF-OLEDs needs improving so as to meet the requirement of practical applications. [7] Commonly, TSF-OLED features a typical emitting layer (EML) of a ternary system with a wide-energy-gap host, a TADF sensitizer and a CFD. Avoiding energy loss through the triplet (T 1 ) states of CFDs, formed by Dexter energy transfer (DET) from the T 1 s of the host and the TADF sensitizer, is the key for high device efficiency, which highly depends on the interplay of the components in the EMLs. In our previous work, we have revealed that CFD with electronically inert steric substituents can suppress the DET process by enlarging the distance of its electronically active core with the adjacent molecule, based on the fact that DET is a shortrange, efficient orbital-overlapping required interaction. [8] Later, such molecular design concept was also been adopted by TADF sensitizers to prevent DET. [9] But the enlarged intermolecular distance may also weaken the desired Förster energy transfer (FET). [10] To overcome this issue, we first introduced interfacial exciplex systems as the wide-energy-gap host to trigger multiple sensitizing processes, greatly enhancing FET meanwhile suppressing DET. [8,11] Consequently, the exciton loss pathways were successfully blocked and a maximum external quantum efficiency (EQE max ) as high as 24% was realized. After that, Liao and coworkers also introduced bulky exciplex system as the host to harness triplet excitons. [12] Those results validate the effectiveness of manipulating the EML components to maximize the device performances. However, the exciplex systems would increase the complexity of the device fabrication process and more importantly, the lack of efficient blue exciplex systems limits the versatility of this strategy. [7] Possessing higher up-conversion efficiencies, more flexible molecular structures and more feasible color-turnabilities than exciplex systems, single-molecular TADF materials also Comprising an emitting layer (EML) constituting a wide-energy-gap host, a thermally activated delayed fluorescence (TADF) sensitizer and a conventional fluorescent dopant, TADF-sensitizing-fluorescence organic light-emitting diodes (TSF-OLEDs) highly depend on component interplay to maximize their performance, which, however, is still under-researched. Taking the host type (TADF or non-TADF) and the recombination position (on the host or on the TADF sensitizer) into consideration, the interplay of host and TADF sensitizer is comprehensively studied and manipulated. A wide-energy-gap host with TADF and recombination of charges on it are both required to m...