Type I interferon is critical for the homeostasis and functional maturation of type 3 γδ T cells

Iridium­(III) cyclometalates (<b>1c</b> and <b>2c</b>) in which the two carborane units on the 4- or 5-positions of 2-phenylpyridine (ppy) ligands were tethered by an alkylene linker were prepared to investigate the effect of free rotation of <i>o</i>-carborane on phosphorescence efficiency. In comparison with the unlinked complex, tethering the <i>o</i>-carboranes to the 5-positions of ppy ligands (<b>2c</b>) enhanced phosphorescence efficiency by over 30-fold in polar medium (Φ_PL = 0.37 vs 0.011 in THF), while restricting the rotation of <i>o</i>-carborane at the 4-positions (<b>1c</b>) negatively affected the phosphorescence efficiency. The different effects of restricted rotation of <i>o</i>-carborane on phosphorescence efficiency were likely a result of the different variations of the carboranyl C–C bond distances in the excited state

<i>p</i>- and <i>n</i>‑type Doping Effects on the Electrical and Ionic Conductivities of Li₄Ti₅O₁₂ Anode Materials

We systematically investigated p- and n-type doping effects on the electrical conductivity of spinel Li₄Ti₅O₁₂ (LTO) by designing theoretically stoichiometric Li₁₁Ti₁₃O₃₂ (p-type) and Li₁₀Ti₁₄O₃₂ (n-type) because LTO has a nonstoichiometric (Li)₈[Li_8/3Ti_40/3]­O₃₂ formula with the <i>Fd</i>3<i>m̅</i> space group. In this work, we present evidence that the electronic modification plays a fundamental role in the electrical conductivity of LTO, especially, n-type Li₁₀Ti₁₄O₃₂, which has superior electrical conductivity compared to p-type Li₁₁Ti₁₃O₃₂. We proposed a way to improve the electrical conductivity of pristine LTO by halogen ion doping, Li₄Ti₅O_{12–<i>x</i>}Hal_<i>x</i> (Hal: F, Cl, and Br), for an n-type doping effect. However, the substitution of halogen ions can enhance the electrical conductivity by mixing Ti⁴⁺/Ti³⁺ and impede the Li ion diffusion in the lattice. The larger size of Cl and Br increases the Li ion diffusion energy barrier with van der Waals repulsion. Therefore, our theoretical investigations of the effects of halogen doping on the electrical and ionic conductivities anticipate that the smaller-sized F may be the most promising dopant for improving the performance of LTO

<i>o</i>‑Carboranyl–Phosphine as a New Class of Strong-Field Ancillary Ligand in Cyclometalated Iridium(III) Complexes: Toward Blue Phosphorescence

Heteroleptic tris-cyclometalated Ir­(III) complexes supported by the <i>o</i>-carboranyl–phosphine ligand (<i>CBP</i>), (C^∧N)₂Ir­(<i>CBP</i>) (C^∧N = <i>ppy</i> (<b>1</b>), <i>dfppy</i> (<b>2</b>)), have been synthesized and characterized. The PL spectra of <b>1</b> and <b>2</b> displayed substantially blue shifted phosphorescence relative to the corresponding Ir­(C^∧N)₃ complexes. Electrochemical and theoretical studies showed that the <i>CBP</i> ligand functioned as a strong-field ancillary ligand, and the greater HOMO stabilization in comparison to that of the LUMO by the <i>CBP</i> ligand was responsible for the increase in band gap, leading to a large blue shift in phosphorescence

Selective Synthesis of Ruthenium(II) Metalla[2]Catenane via Solvent and Guest-Dependent Self-Assembly

The coordination-driven self-assembly of an anthracene-functionalized ditopic pyridyl donor and a tetracene-based dinuclear Ru­(II) acceptor resulted in an interlocked metalla[2]­catenane, [M₂L₂]₂, in methanol and a corresponding monorectangle, [M₂L₂], in nitromethane. Subsequently, guest template, solvent, and concentration effects allowed the self-assembly to be reversibly fine-tuned among monorectangle and catenane structures

Terpyridine–Triarylborane Conjugates for the Dual Complexation of Zinc(II) Cation and Fluoride Anion

A series of ditopic terpyridine–triarylborane conjugates (<b>1</b>–<b>3</b>) in which 4′-ethynylterpyridine is linked to the para, meta, and ortho positions of the phenyl ring of dimesitylphenylborane (Mes₂PhB), respectively, were prepared to investigate the dual complexation behavior of the conjugates toward Zn­(II) cation and fluoride anion. The crystal structures of the corresponding Zn­(II) complexes (<b>L</b>·ZnCl₂, <b>L</b> = <b>1</b>–<b>3</b>) reveal the formation of a 1:1 adduct between ZnCl₂ and a conjugate, with a five-coordinate Zn­(II) center bound to three nitrogen atoms and two chlorine atoms. In particular, the structure of ortho-substituted <b>3</b>·ZnCl₂ in comparison with that of <b>3</b> indicates the presence of π–π interactions between the mesityl ring and ethynylene–pyridine fragment in <b>3</b>·ZnCl₂. UV/vis absorption and fluorescence spectra of <b>1</b>–<b>3</b> display low-energy bands mainly assignable to a π­(Ar) → p_π(B) (Ar = Mes and/or phenylene–ethynylene) charge transfer (CT) transition. The transition in Zn­(II) complexes has a π­(Mes) → π*­(Ar) (Ar = terpyridine–ethynylene) intramolecular CT nature with red shifts of both the absorption and emission bands in comparison to those of free conjugates. These spectroscopic features are further supported by TD-DFT calculations. UV/vis absorption and fluorescence titration experiments of <b>1</b>–<b>3</b> toward Zn­(II) and fluoride ion, respectively, show that while the absorption and fluorescence bands underwent gradual quenching upon addition of fluoride, the addition of ZnCl₂ gave rise to the red shifts of both bands. Fluoride titration experiments of Zn­(II) complexes also resulted in gradual quenching of both the absorption and emission bands accompanied by the disappearance of emission color. Sequential addition of ZnCl₂ and fluoride to the conjugates reproduced the above binding behavior with an emission color change from deep blue to sky blue to dark

Terpyridine–Triarylborane Conjugates for the Dual Complexation of Zinc(II) Cation and Fluoride Anion

A series of ditopic terpyridine–triarylborane conjugates (<b>1</b>–<b>3</b>) in which 4′-ethynylterpyridine is linked to the para, meta, and ortho positions of the phenyl ring of dimesitylphenylborane (Mes₂PhB), respectively, were prepared to investigate the dual complexation behavior of the conjugates toward Zn­(II) cation and fluoride anion. The crystal structures of the corresponding Zn­(II) complexes (<b>L</b>·ZnCl₂, <b>L</b> = <b>1</b>–<b>3</b>) reveal the formation of a 1:1 adduct between ZnCl₂ and a conjugate, with a five-coordinate Zn­(II) center bound to three nitrogen atoms and two chlorine atoms. In particular, the structure of ortho-substituted <b>3</b>·ZnCl₂ in comparison with that of <b>3</b> indicates the presence of π–π interactions between the mesityl ring and ethynylene–pyridine fragment in <b>3</b>·ZnCl₂. UV/vis absorption and fluorescence spectra of <b>1</b>–<b>3</b> display low-energy bands mainly assignable to a π­(Ar) → p_π(B) (Ar = Mes and/or phenylene–ethynylene) charge transfer (CT) transition. The transition in Zn­(II) complexes has a π­(Mes) → π*­(Ar) (Ar = terpyridine–ethynylene) intramolecular CT nature with red shifts of both the absorption and emission bands in comparison to those of free conjugates. These spectroscopic features are further supported by TD-DFT calculations. UV/vis absorption and fluorescence titration experiments of <b>1</b>–<b>3</b> toward Zn­(II) and fluoride ion, respectively, show that while the absorption and fluorescence bands underwent gradual quenching upon addition of fluoride, the addition of ZnCl₂ gave rise to the red shifts of both bands. Fluoride titration experiments of Zn­(II) complexes also resulted in gradual quenching of both the absorption and emission bands accompanied by the disappearance of emission color. Sequential addition of ZnCl₂ and fluoride to the conjugates reproduced the above binding behavior with an emission color change from deep blue to sky blue to dark

Exploring Interfacial Events in Gold-Nanocluster-Sensitized Solar Cells: Insights into the Effects of the Cluster Size and Electrolyte on Solar Cell Performance

Gold nanoclusters (Au NCs) with molecule-like behavior have emerged as a new light harvester in various energy conversion systems. Despite several important strides made recently, efforts toward the utilization of NCs as a light harvester have been primarily restricted to proving their potency and feasibility. In solar cell applications, ground-breaking research with a power conversion efficiency (PCE) of more than 2% has recently been reported. Because of the lack of complete characterization of metal cluster-sensitized solar cells (MCSSCs), however, comprehensive understanding of the interfacial events and limiting factors which dictate their performance remains elusive. In this regard, we provide deep insight into MCSSCs for the first time by performing in-depth electrochemical impedance spectroscopy (EIS) analysis combined with physical characterization and density functional theory (DFT) calculations of Au NCs. In particular, we focused on the effect of the size of the Au NCs and electrolytes on the performance of MCSSCs and reveal that they are significantly influential on important solar cell characteristics such as the light absorption capability, charge injection kinetics, interfacial charge recombination, and charge transport. Besides offering comprehensive insights, this work represents an important stepping stone toward the development of MCSSCs by accomplishing a new PCE record of 3.8%

Hierarchically Designed 3D Holey C₂N Aerogels as Bifunctional Oxygen Electrodes for Flexible and Rechargeable Zn-Air Batteries

The future of electrochemical energy storage spotlights on the designed formation of highly efficient and robust bifunctional oxygen electrocatalysts that facilitate advanced rechargeable metal-air batteries. We introduce a scalable facile strategy for the construction of a hierarchical three-dimensional sulfur-modulated holey C₂N aerogels (S-C₂NA) as bifunctional catalysts for Zn-air and Li-O₂ batteries. The S-C₂NA exhibited ultrahigh surface area (∼1943 m² g^–1) and superb electrocatalytic activities with lowest reversible oxygen electrode index ∼0.65 V, outperforms the highly active bifunctional and commercial (Pt/C and RuO₂) catalysts. Density functional theory and experimental results reveal that the favorable electronic structure and atomic coordination of holey C–N skeleton enable the reversible oxygen reactions. The resulting Zn-air batteries with liquid electrolytes and the solid-state batteries with S-C₂NA air cathodes exhibit superb energy densities (958 and 862 Wh kg^–1), low charge–discharge polarizations, excellent reversibility, and ultralong cycling lives (750 and 460 h) than the commercial Pt/C+RuO₂ catalysts, respectively. Notably, Li-O₂ batteries with S-C₂NA demonstrated an outstanding specific capacity of ∼648.7 mA h g^–1 and reversible charge–discharge potentials over 200 cycles, illustrating great potential for commercial next-generation rechargeable power sources of flexible electronics

Aggregation and Stabilization of Carboxylic Acid Functionalized Halloysite Nanotubes (HNT-COOH)

We modified the functional groups of holloysite nanotubes (HNT) from hydroxyl groups (HNT-OH) to carboxylic acids (HNT-COOH). Aggregation and dispersion properties of HNT-COOH under dry conditions were probed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Moreover, the degree of aggregation and dispersion of HNT-COOH in acidic, basic, and neutral solutions were measured by multiple angle polarized dynamic light scattering (MA-DLS). HNT-COOH formed aggregates in neutral solution; however, the material was dispersed in basic and acidic solutions. This occurrence is due to hydrogen bonds (HB) between the carboxyl groups of HNT-COOH in neutral solution, which decrease in acidic and basic solution due to charge dispersion

NbO₂ a Highly Stable, Ultrafast Anode Material for Li- and Na-Ion Batteries

Anode materials with fast charging capabilities and stability are critical for realizing next-generation Li-ion batteries (LIBs) and Na-ion batteries (SIBs). The present work employs a simple synthetic strategy to obtain NbO2 and studies its applications as an anode for LIB and SIB. In the case of the LIB, it exhibited a specific capacity of 344 mAh g–1 at 100 mA g–1. It also demonstrated remarkable stability over 1000 cycles, with 92% capacity retention. Additionally, it showed a unique fast charging capability, which takes 30 s to reach a specific capacity of 83 mAh g–1. For the SIB, NbO2 exhibited a specific capacity of 244 mAh g–1 at 50 mA g–1 and showed 70% capacity retention after 500 cycles. Furthermore, detailed density functional theory reveals that various factors like bulk and surface charging processes, lower ion diffusion energy barriers, and superior electronic conductivity of NbO2 are responsible for the observed battery performances