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2D compounds exfoliated from weakly bonded bulk materials with van der Waals (vdW) interaction are easily accessible. However, the strong internal ionic/covalent bonding of most inorganic crystal frameworks greatly hinders 2D material exfoliation. Herein, we first proposed a radical/strain‐synergistic strategy to exfoliate non‐vdW interacting pseudo‐layered phosphate framework. Specifically, hydroxyl radicals (⋅OH) distort the covalent bond irreversibly, meanwhile, H2O molecules as solvents, further accelerating interlayered ionic bond breakage but mechanical expansion. The innovative 2D laminar NASICON‐type Na3V2(PO4)2O2F crystal, exfoliated by ⋅OH/H2O synergistic strategy, exhibits enhanced sodium‐ion storage capacity, high‐rate performance (85.7 mAh g−1 at 20 C), cyclic life (2300 cycles), and ion migration rates, compared with the bulk framework. Importantly, this chemical/physical dual driving technique realized the effective exfoliation for strongly coupled pseudo‐layered frameworks, which accelerates 2D functional material development. [ABSTRACT FROM AUTHOR]

Polynuclear metal hydride clusters play important roles in various catalytic processes, with most of the reported polynuclear metal hydride clusters adopting a polyhedral three‐dimensional structure. Herein, we report the first example of a planar tetranuclear uranium hydride cluster [(CpCMe2CMe2Cp)U]4(μ2‐H)4(μ3‐H)4 (U4H8). It was synthesized by reacting an ansa‐bis(cyclopentadienyl) ligand‐supported uranium chloride precursor [(CpCMe2CMe2Cp)U]3(μ2‐Cl)3(μ3‐Cl)2 with NaHBEt3. The presence of hydrides in U4H8 was confirmed by NMR spectroscopy and its reactivity with phenol and carbon tetrachloride. DFT calculations also facilitated the determination of the hydrides' positions in U4H8, featuring four bridging μ2‐H ligands and four face‐capping μ3‐H ligands, with the four U centers arranged in a rhombic geometry. The U4H8 represents not only the first example of planar polynuclear actinide metal hydride cluster but also the uranium hydride cluster with the highest nuclearity reported to date. [ABSTRACT FROM AUTHOR]

Monoatomic dispersion of precious metals on the surface of CeO2 nanocrystals is a highly practical approach for dramatically reducing the usage of precious metals while exploiting the unique properties of single‐atom catalysts. However, the specific atomic sites for anchoring precious metal atoms on the CeO2 support and underlying chemical mechanism remain partially unknown. Herein, we show that the terminal hydroxyls on the (100) surface are the most stable sites for anchoring Ag atoms on CeO2, indicating that CeO2 nanocubes are the most efficient substrates to achieve monoatomic dispersion of Ag. Importantly, the newly identified chemical mechanism for single‐metal‐atom dispersion on CeO2 nanocubes appears to be generic and can thus be extended to other precious metals (Pt and Pd). In fact, our experiments also show that atomically dispersed Pt/Pd species exhibit morphology‐ and temperature‐dependent CO selectivity in the catalytic CO2 hydrogenation reaction. [ABSTRACT FROM AUTHOR]

B‐ and N‐embedded multiple resonance (MR) type thermally activated delayed fluorescence (TADF) emitters usually suffer from slow reverse intersystem crossing (RISC) process and aggregation‐caused emission quenching. Here, we report the design of a sandwich structure by placing the B−N MR core between two electron‐donating moieties, inducing through‐space charge transfer (TSCT) states. The proper adjusting of the energy levels brings about a 10‐fold higher RISC rate in comparison with the parent B−N molecule. In the meantime, a high photoluminescence quantum yield of 91 % and a good color purity were maintained. Organic light‐emitting diodes based on the new MR emitter achieved a maximum external quantum efficiency of 31.7 % and small roll‐offs at high brightness. High device efficiencies were also obtained for a wide range of doping concentrations of up to 20 wt % thanks to the steric shielding of the B−N core. A good operational stability with LT95 of 85.2 h has also been revealed. The dual steric and electronic effects resulting from the introduction of a TSCT state offer an effective molecular design to address the critical challenges of MR‐TADF emitters. [ABSTRACT FROM AUTHOR]

The promotion of intersystem crossing (ISC) is critical for achieving a high‐efficiency long‐persistent luminescence (LPL) from organic materials. However, the use of a transition‐metal complex for LPL materials has not been explored because it can also shorten the emission lifetime by accelerating the phosphorescence decay. Here, we report a new class of LPL materials by doping a monovalent Au‐carbene complex into a boron‐embedded molecular host. The donor‐acceptor systems exhibit photoluminescence with both high efficiencies (>57 %) and long lifetimes (ca. 40 ms) at room temperature. It is revealed that the Au atom promotes the population of low‐lying triplet excited states of the host aggregate (T1*) which can be converted into the charge‐transfer (CT) state, thereby resulting in afterglow luminescence. Moreover, the use of a chirality unit on the guest molecule results in the LPL being circularly polarized. This work illustrates that transition‐metal complexes can be used for developing organic afterglow systems by exquisite control over the excited state mechanism. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrogen reduction reaction (NRR) under ambient conditions provides an intriguing pathway to convert N2 into NH3. However, significant kinetic barriers of the NRR at low temperatures in desirable aqueous electrolytes remain a grand challenge due to the inert N≡N bond of the N2 molecule. Herein, we propose a unique strategy for in situ oxygen vacancy construction to address the significant trade‐off between N2 adsorption and NH3 desorption by building a hollow shell structured Fe3C/Fe3O4 heterojunction coated with carbon frameworks (Fe3C/Fe3O4@C). In the heterostructure, the Fe3C triggers the oxygen vacancies of the Fe3O4 component, which are likely active sites for the NRR. The design could optimize the adsorption strength of the N2 and NxHy intermediates, thus boosting the catalytic activity for the NRR. This work highlights the significance of the interaction between defect and interface engineering for regulating electrocatalytic properties of heterostructured catalysts for the challenging NRR. It could motivate an in‐depth exploration to advance N2 reduction to ammonia. [ABSTRACT FROM AUTHOR]

Replacing the oxygen evolution reaction (OER) with the thermodynamically favorable electrooxidation of organics is considered a promising approach for the simultaneous production of hydrogen (H2) and high‐value chemicals. However, exploring and optimizing efficient electrocatalysts remains a challenge for large‐scale production of value‐added steroid carbonyl and H2. Herein, Cr‐NiO/GF and Cr‐Ni3N/GF (GF: graphite felt) electrocatalysts were designed as anode and cathode for the production of steroid carbonyls and H2, respectively. The cooperative Cr‐NiO and ACT (4‐acetamido‐2,2,6,6‐tetramethyl‐1‐piperidine‐N‐oxyl) electrocatalyst can be extended to the electrooxidation of a series of steroid alcohols to the corresponding aldehydes. Additionally, Cr‐Ni3N displays superior electrocatalytic activity for hydrogen evolution reaction (HER), with a low overpotential of 35 mV to deliver 10 mA cm−2. Furthermore, the system coupled with anodic electrooxidation of sterol and cathodic HER exhibited excellent performance with high space‐time yield of 48.85 kg m−3 h−1 for steroid carbonyl and 1.82 L h−1 for H2 generation in a two‐layer stacked flow cell. Density Functional Theory (DFT) calculations indicated that Cr doping effectively stabilizes ACTH on the NiO surface, and ACTH molecule could be captured via the ketonic oxygen interaction with Cr, resulting in excellent electrocatalytic activity. This work develops a novel approach to the rational design of efficient electrocatalysts for the simultaneous production of H2 and large‐scale value‐added pharmaceutical carbonyl intermediates. [ABSTRACT FROM AUTHOR]

A recent research article in Angewandte Chemie International Edition discusses a new method for creating a 2D phosphate material with improved properties for use in sodium-ion battery cathodes. The researchers used radicals and water molecules to break V-F-V bonds in bulk phase phosphate, resulting in the formation of a new 2D phosphate through recoordination. This 2D phosphate demonstrated enhanced carrier transport capability, lower Na+ migration barriers, and reduced volumetric strain, making it ideal for fast charging in sodium-ion batteries. The findings of this study offer valuable insights for the optimization of sodium-ion batteries. [Extracted from the article]

A molecular design to high‐performance red and near‐infrared (NIR) organic light‐emitting diodes (OLEDs) emitters remains demanding. Herein a series of dinuclear platinum(II) complexes featuring strong intramolecular Pt⋅⋅⋅Pt and π–π interactions has been developed by using N‐deprotonated α‐carboline as a bridging ligand. The complexes in doped thin films exhibit efficient red to NIR emission from short‐lived (τ=0.9–2.1 μs) triplet metal‐metal‐to‐ligand charge transfer (3MMLCT) excited states. Red OLEDs demonstrate high maximum external quantum efficiencies (EQEs) of up to 23.3 % among the best PtII‐complex‐doped devices. The maximum EQE of 15.0 % and radiance of 285 W sr−1 m−2 for NIR OLEDs (λEL=725 nm) are unprecedented for devices based on discrete molecular emitters. Both red and NIR devices show very small efficiency roll‐off at high brightness. Appealing operational lifetimes have also been revealed for the devices. This work sheds light on the potential of intramolecular metallophilicity for long‐wavelength molecular emitters and electroluminescence. [ABSTRACT FROM AUTHOR]

Intramolecular through‐space charge‐transfer (TSCT) excited states have been exploited for developing thermally activated delayed fluorescence (TADF) emitters, but the tuning of excited state dynamics by conformational engineering remains sparse. Designed here is a series of TSCT emitters with precisely controlled alignment of the donor and acceptor segments. With increasing intramolecular π–π interactions, the radiative decay rate of the lowest singlet excited state (S1) progressively increased together with a suppression of nonradiative decay, leading to significantly enhanced photoluminescence quantum yields of up to 0.99 in doped thin films. A high‐efficiency electroluminescence device, with a maximum external quantum efficiency (EQE) of 23.96 %, was achieved and maintains >20 % at a brightness of 1000 cd m−2. This work sheds light on the importance of conformation control for achieving high‐efficiency intramolecular exciplex emitters. [ABSTRACT FROM AUTHOR]

Pathogen infections and cancer are two major human health problems. Herein, we report the synthesis of an organic salt photosensitizer (PS), called 4TPA‐BQ, by a one‐step reaction. 4TPA‐BQ presents aggregation‐induced emission features. Owing to the aggregation‐induced reactive oxygen species generated and a sufficiently small ΔEST, 4TPA‐BQ shows a satisfactorily high 1O2 generation efficiency of 97.8 %. In vitro and in vivo experiments confirmed that 4TPA‐BQ exhibited potent photodynamic antibacterial performance against ampicillin‐resistant Escherichia coli with good biocompatibility in a short time (15 minutes). When the incubation duration persisted long enough (12 hours), cancer cells were ablated efficiently, leaving normal cells essentially unaffected. This is the first reported time‐dependent fluorescence‐guided photodynamic therapy in one individual PS, which achieves ordered and multiple targeting simply by varying the external conditions. 4TPA‐BQ reveals new design principles for the implementation of efficient PSs in clinical applications. [ABSTRACT FROM AUTHOR]

Two‐coordinate coinage metal complexes have been exploited for various applications. Herein, a new donor‐metal‐acceptor (D–M–A) complex PZI‐Au‐TOT, using bulky pyrazine‐fused N‐heterocyclic carbene (PZI) and trioxytriphenylamine (TOT) ligands, was synthesized. PZI‐Au‐TOT displays decent thermally activated delayed fluorescence (TADF) with a quantum yield of 93 % in doped film. The crystals of PZI‐Au‐TOT show simultaneous TADF, polymorphism, and linearly polarized luminescence (LPL). The polymorph‐dependent emission properties with widely varied peaks from 560 to 655 nm are attributed to different packing modes in terms of isolated monomers, discrete π–π stacked dimers or dimer PLUS. Two well‐defined microcrystals of PZI‐Au‐TOT exhibit linearly polarized thermally activated delayed fluorescence with a degree of polarization up to 0.64. This work demonstrates that the molecular rotational flexibility of D–M–A type complexes endows an integration of multiple functions into one complex through manipulation of supramolecular aggregation. This type of complexes is expected to serve as a versatile platform for the fabrication of crystal materials for advanced photonic applications. [ABSTRACT FROM AUTHOR]

Multi‐resonance (MR) type emitters have emerged as highly promising candidates for high‐resolution organic light‐emitting diodes (OLEDs). However, thermally activated delayed fluorescence (TADF) emissions with simultaneous short excited state lifetimes and ultrapure blue color (a CIEy close to 0.046 and an emission peak >440 nm) have rarely been obtained for MR emitters. Herein, we report a design of dual gold‐coordinated MR molecules to achieve efficient and short‐lived ultrapure blue TADF emission. The dinuclear Au(I) complex, namely iPrAuBN, shows a narrowband deep‐blue emission with a peak maximum of 448 nm and a full width at half maximum (FWHM) of 29 nm in doped film. The coordination with two Au atoms significantly shortens the delayed fluorescence lifetime to 7.8 μs in comparison to 60.6 μs for the parental organic analogue. Solution‐processed OLED doped with iPrAuBN demonstrates an ultrapure blue electroluminescence with a peak maximum of 442 nm, a FWHM of 19 nm, CIE coordinates of (0.154, 0.036), and a maximum external quantum efficiency of 14.8 %. [ABSTRACT FROM AUTHOR]