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We synthesized three materials, namely, TDBA-Ge, mTDBA-Ge, and mTDBA-2Ge, as blue host emitters. These materials incorporate a tetraphenylgermanium (TPG) group with a germanium atom into the main backbone of 5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracene (DOBNA), demonstrating multiple-resonance-induced thermally activated delayed fluorescence (MR-TADF). All three materials exhibited high thermal stability with a glass transition temperature (Tg) exceeding 100 °C. The increased molecular distance also demonstrated the inhibition of self-quenching between molecules in the packing. All three materials showed ΔEST values within 0.3 eV, confirming their potential for MR-TADF characteristics. Especially, mTDBA-2Ge exhibited the lowest ΔEST value of 0.11 eV among the three materials. When these host materials were doped with the conventional dopant ν-DABNA, efficient energy transfer between the two materials was observed, and the resulting device efficiency was confirmed. In comparison to TDBA-Ph, which lacks the TPG moiety and contains only phenyl groups, an approximately 1.5–1.8-fold increase in external quantum efficiency max (EQEmax) was observed. Among the three materials, mTDBA-2Ge exhibited the highest efficiency, with an EQEmax of 24.41%. [ABSTRACT FROM AUTHOR]

Nanostructured ionic compounds have driven major technological advancements in displays, photovoltaics, and catalysis. Current research focuses on refining the chemical composition of such compounds. In this study, a strategy for creating stoichiometrically well‐defined nanoscale multiple‐cation systems, where the atomically precise structure maximizes the synergistic cooperation between cations at the atomic scale is reported. The unprecedented construction of Heusler‐type PtRuP2 double‐walled nanotubes through sequential anion/cation exchange reactions is demonstrated. The PtRuP2 catalyst exhibits record‐high catalytic performance and durability for the hydrogen evolution reaction (HER) in alkaline electrolytes and anion‐exchange membrane water electrolyzers. The investigations highlight the crucial role of Pt/Ru dual centers, providing multiple active sites that accelerate the HER kinetics within a single phosphide material, in the sequential operation of H2O activation/dissociation at Ru and H2 production at adjacent Pt sites. These findings open new avenues for optimizing ionic compound‐based HER electrocatalysts, offering platinum‐metal alternatives in acidic and alkaline media. [ABSTRACT FROM AUTHOR]

Repetitive stimulation procedures are used in neuromodulation techniques to induce persistent excitatory or inhibitory brain activity. The directivity of modulation is empirically regulated by modifying the stimulation length, interval, and strength. However, bidirectional neuronal modulations using ultrasound stimulations are rarely reported. This study presents bidirectional control of epileptiform activities with repetitive transcranial‐focused ultrasound stimulations in a rat model of drug‐induced acute epilepsy. It is found that repeated transmission of elongated (40 s), ultra‐low pressure (0.25 MPa) ultrasound can fully suppress epileptic activities in electro‐encephalography and cerebral blood volume measurements, while the change in bursting intervals from 40 to 20 s worsens epileptic activities even with the same burst length. Furthermore, the suppression induced by 40 s long bursts is transformed to excitatory states by a subsequent transmission. Bidirectional modulation of epileptic seizures with repeated ultrasound stimulation is achieved by regulating the changes in glutamate and γ‐Aminobutyric acid levels, as confirmed by measurements of expressed c‐Fos and GAD65 and multitemporal analysis of neurotransmitters in the interstitial fluid obtained via microdialysis. [ABSTRACT FROM AUTHOR]

The popularly used global, meta‐GGA, and range‐separated hybrid DFT functionals are examined to compare the predictive qualities of singlet excited state (S1) properties in HLCT materials. Among these hybrid DFT functionals, it is clarified that both M06 and LC‐ω*HPBE functionals show quantitatively and qualitatively excellent predictions of absorption energies, compared to experiments. However, a discrepant behavior in predicting the emission energy is found that LC‐ω*HPBE functional obviously predicts more accurate emission energy than M06 functional. Also, the calculated τs values by means of M06 and LC‐ω∗HPBE functionals show that LC‐ω∗HPBE functional gives quantitatively and qualitatively superior prediction. Consequently, it is suggested that LC‐ω*HPBE functional should be used to conduct the essential photo‐physical properties of HLCT materials in S1 state. [ABSTRACT FROM AUTHOR]