Solution-Processed Hybrid Europium (II) Iodide Scintillator for Sensitive X-Ray Detection.

Lead halide perovskite nanocrystals have recently demonstrated great potential as x-ray scintillators, yet they still suffer toxicity issues, inferior light yield (LY) caused by severe self-absorption. Nontoxic bivalent europium ions (Eu) with intrinsically efficient and self-absorption-free transition are a prospective replacement for the toxic Pb. Here, we demonstrated solution-processed organic-inorganic hybrid halide BAEuI (BA denotes CHNH) single crystals for the first time.

Excited-State Dopant-Host Energy-Level Alignment: Toward a Better Understanding of the Photoluminescence Behaviors of Doped Phosphors.

Luminescent materials, also known as phosphors, have been widely used for applications such as emissive displays, fluorescent lamps, light-emitting diodes, and X-ray scintillation detectors. The energy-level diagram of a phosphor is extremely important for understanding its photoluminescence behavior. Here, we demonstrate through a combined density functional theory and experimental study that excited-state energy-level alignment accounts for the photoluminescence behaviors much better than ground-state energy-level alignment.

Ultrathin quantum light source with van der Waals NbOCl crystal.

Interlayer electronic coupling in two-dimensional materials enables tunable and emergent properties by stacking engineering. However, it also results in significant evolution of electronic structures and attenuation of excitonic effects in two-dimensional semiconductors as exemplified by quickly degrading excitonic photoluminescence and optical nonlinearities in transition metal dichalcogenides when monolayers are stacked into van der Waals structures. Here we report a van der Waals crystal, niobium oxide dichloride (NbOCl), featuring vanishing interlayer electronic coupling and monolayer-like excitonic behaviour in the bulk form, along with a scalable second-harmonic generation intensity of up to three orders higher than that in monolayer WS.

Highly Distorted Antimony(III) Chloride [Sb Cl ] Dimers for Near-Infrared Luminescence up to 1070 nm.

Zero-dimensional (0D) hybrid metal halides with unique compositional and structural tunability appear as an emerging class of luminescent materials, but near-infrared (NIR) emitters therein are largely unexplored to date. This study presents three novel 0D hybrid antimony chlorines with edge-sharing [Sb Cl ] dimers, showing unusual room-temperature broadband NIR emission with the maximum emission wavelength up to 1070 nm. Photoluminescence studies and density functional theory calculation demonstrate that the emissions originate from the highly localized excitons, and that the confined [Sb Cl ] dimers in these structures show low symmetry and a large degree of structural freedom.

Chemical Potential Diagram Guided Rational Tuning of Electrical Properties: A Case Study of CsPbBr for X-ray Detection.

Controlling the carrier polarity and concentration underlies most electronic and optoelectronic devices. However, for the intensively studied lead halide perovskites, the doping tunability is inefficient. In this work, taking CsPbBr as an example, it is revealed that the coexistence of metallic Pb or CsBr /Br , rather than the precursor ratio, can provide Pb-rich/Br-poor or Br-rich/Pb-poor chemical conditions, enabling the tunability of electrical properties from weak n-type, intrinsic, to moderate p-type.

Photoluminescence Behavior of Zero-Dimensional Manganese Halide Tetrahedra Embedded in Conjugated Organic Matrices.

Zero-dimensional hybrid manganese halides with the type-I band alignment between the manganese halide tetrahedra and organic matrices have attracted much attention as highly efficient narrow-band green emitters. Herein we study the photoluminescence (PL) behavior of hybrid manganese bromides with type-II band alignment, where the lowest unoccupied molecular orbital (LUMO) level can be tuned by employing quaternary phosphonium dications with different degrees of conjugation. For low-conjugated organic matrices, the band alignment can shift from type II in the ground state to type I in the excited state, which enables high photoluminescence quantum yields.

B-Site Columnar-Ordered Halide Double Perovskites: Theoretical Design and Experimental Verification.

Halide double perovskites AB(I)B(III)X, in which monovalent B(I) and trivalent B(III) cations are arranged in the B-sites of the perovskite structure with a rock-salt ordering, have attracted substantial interest in the field of optoelectronics. However, the rock-salt ordering generally leads to low electronic dimensionality, with relatively large bandgaps and large carrier effective masses. In this work, we demonstrate, by density functional theory (DFT) calculations, that the electronic dimensionality and thus the electronic properties of halide double perovskites can be effectively modulated by manipulating the arrangement of the B-site cations.

Material exploration via designing spatial arrangement of octahedral units: a case study of lead halide perovskites.

Halide perovskites have attracted tremendous attention as semiconducting materials for various optoelectronic applications. The functional metal-halide octahedral units and their spatial arrangements play a key role in the optoelectronic properties of these materials. At present, most of the efforts for material exploration focus on substituting the constituent elements of functional octahedral units, whereas designing the spatial arrangement of the functional units has received relatively little consideration.

Slot-die coating large-area formamidinium-cesium perovskite film for efficient and stable parallel solar module.

Perovskite solar cells have emerged as one of the most promising thin-film photovoltaic (PV) technologies and have made a strong debut in the PV field. However, they still face difficulties with up-scaling to module-level devices and long-term stability issue. Here, we report the use of a room-temperature nonvolatile Lewis base additive, diphenyl sulfoxide(DPSO), in formamidinium-cesium (FACs) perovskite precursor solution to enhance the nucleation barrier and stabilize the wet precursor film for the scalable fabrication of uniform, large-area FACs perovskite films.

5-Hydroxymethylcytosine signature in circulating cell-free DNA as a potential diagnostic factor for early-stage colorectal cancer and precancerous adenoma.

Approximately 85% colorectal cancers (CRCs) are thought to evolve through the adenoma-to-carcinoma sequence associated with specific molecular alterations, including the 5-hydroxymethylcytosine (5hmC) signature in circulating cell-free DNA (cfDNA). To explore colorectal disease progression and evaluate the use of cfDNA as a potential diagnostic factor for CRC screening, here, we performed genome-wide 5hmC profiling in plasma cfDNA and tissue genomic DNA (gDNA) acquired from 101 samples (63 plasma and 38 tissues), collected from 21 early-stage CRC patients, 21 AD patients, and 21 healthy controls (HC). The gDNA and cfDNA 5hmC signatures identified in gene bodies and promoter regions in CRC and AD groups were compared with those in HC group.

Rearranging Low-Dimensional Phase Distribution of Quasi-2D Perovskites for Efficient Sky-Blue Perovskite Light-Emitting Diodes.

Metal halide perovskites have received much attention for their application in light-emitting diodes (LEDs) in the past several years. Rapid progress has been made in efficient green, red, and near-infrared perovskite LEDs. However, the development of blue perovskite LEDs is still lagging far behind.

Unraveling the Near-Unity Narrow-Band Green Emission in Zero-Dimensional Mn-Based Metal Halides: A Case Study of (CHN)ZnMnBr Solid Solutions.

Zero-dimensional (0D) Mn-based metal halides are potential candidates as narrow-band green emitters, and thus it is critical to provide a structural understanding of the photophysical process. Herein, we propose that a sufficiently long Mn-Mn distance in 0D metal halides enables all Mn centers to emit spontaneously, thereby leading to near-unity photoluminescence quantum yield. Taking lead-free (CHN)ZnMnBr ( = 0-1) solid solution as an example, the Zn/Mn alloying inhibits the concentration quenching that is caused by the energy transfer of Mn.

Lead-Free Perovskite Variant Solid Solutions Cs Sn Te Cl : Bright Luminescence and High Anti-Water Stability.

Underwater lighting is important for the exploration of the underwater world in different areas. It is of great significance for developing underwater emitters with high penetrability, high luminous efficiency, good anti-water stability, and environmental friendliness. Stable lead-free perovskite luminescent materials, represented by vacancy-ordered double perovskites, are worthy of research because they can almost meet the above requirements.

Zero-dimensional hybrid iodobismuthate derivatives: from structure study to photovoltaic application.

The quest for lead-free light-absorbing perovskite materials has long been the target of researchers to make the 'star' material friendly to the commercial market. After a summary of different lead-free solar absorbers, we demonstrate a zero-dimensional iodobismuthate (MA)[BiI]·3MACl (MA: CHNH) featuring isolated hexaiodobismuthate(iii) anions in the crystal analysis. The unexpectedly formed material was made via an orthogonal solvent permeation method and the decomposition of the guest solvent.

Stable single platinum atoms trapped in sub-nanometer cavities in 12CaO·7AlO for chemoselective hydrogenation of nitroarenes.

Single-atom catalysts (SACs) have attracted significant attention because they exhibit unique catalytic performance due to their ideal structure. However, maintaining atomically dispersed metal under high temperature, while achieving high catalytic activity remains a formidable challenge. In this work, we stabilize single platinum atoms within sub-nanometer surface cavities in well-defined 12CaO·7AlO (C12A7) crystals through theoretical prediction and experimental process.

Circularly Polarized Luminescence from Chiral Tetranuclear Copper(I) Iodide Clusters.

Circularly polarized luminescent (CPL) materials are promising in applications such as 3D displays and quantum communication. Hybrid organic-inorganic copper(I) iodides have been rapidly developed due to their intense photoluminescence and structural diversity; nevertheless, the reported Cu-I clusters rarely show CPL activities. In this study, we introduced chiral organic molecules /-methylbenzylammonium (/-MBA) into Cu-I inorganic skeletons to achieve chiral tetranuclear (/-MBA)CuI clusters with intense orange luminescence and CPL activity at room temperature.

Palladium-bearing intermetallic electride as an efficient and stable catalyst for Suzuki cross-coupling reactions.

Suzuki cross-coupling reactions catalyzed by palladium are powerful tools for the synthesis of functional organic compounds. Excellent catalytic activity and stability require negatively charged Pd species and the avoidance of metal leaching or clustering in a heterogeneous system. Here we report a Pd-based electride material, YPd, in which active Pd atoms are incorporated in a lattice together with Y.

Designing Two-Dimensional Properties in Three-Dimensional Halide Perovskites via Orbital Engineering.

Manipulating the orbital hybridization between the metal cation and the halide anion to achieve novel properties is highly desired. Here, we present an orbital engineering strategy to construct two-dimensional (2D) electronic structures in three-dimensional (3D) halide perovskites by rationally controlling the hybridization between the d orbitals of the metal cations and the halide p orbitals. Taking CsAu(I)Au(III)I as an example, we demonstrate that the flat conduction band and valence band at the band edges can be achieved simultaneously by combining two metal cations with different d orbital configurations using first-principles calculations.

Material Design and Optoelectronic Properties of Three-Dimensional Quadruple Perovskite Halides.

The discovery of new halide perovskite-type structures could favor the exploration of optoelectronic materials, as in the case of double perovskites applied in solar cells, light-emitting diodes, and X-ray detectors. In this work, we propose a strategy for designing quadruple perovskites by heterovalent cation transmutation from double perovskites. Two stable quadruple perovskite halides, i.

From Lead Halide Perovskites to Lead-Free Metal Halide Perovskites and Perovskite Derivatives.

Despite the exciting progress on power conversion efficiencies, the commercialization of the emerging lead (Pb) halide perovskite solar cell technology still faces significant challenges, one of which is the inclusion of toxic Pb. Searching for Pb-free perovskite solar cell absorbers is currently an attractive research direction. The approaches used for and the consequences of Pb replacement are reviewed herein.

Multiple states and roles of hydrogen in p-type SnS semiconductors.

Hydrogen (H) plays critical roles in the electrical properties of semiconductor materials and devices. In this work, we report multiple states and roles of H in SnS by H plasma treatment and density functional theory (DFT) calculations. The as-deposited SnS films include impurity H at 2.

CsFeSe: A Compound Closely Related to Alkali-Intercalated FeSe Superconductors.

We report the synthesis and characterizations of a new FeSe-based compound CsFeSe, which is closely related to alkali intercalated FeSe superconductors while exhibits distinct features. It does not undergo phase separation and antiferromagnetic transition. Powder neutron diffractions, electron microscopy and high-angle annular-dark-field images confirm that CsFeSe possesses an ordered Cs arrangement as √2 × √2 superstructure, evidencing a B-centered orthorhombic lattice with a space group of Bmmm.

[Identification of a novel STK11 gene mutation in a family affected with hereditary Peutz-Jeghers syndrome].

OBJECTIVE To explore the genetic basis for a family affected with Peutz-Jeghers syndrome (PJS). METHODS Genomic DNA was extracted from peripheral blood and oral swab samples from the patient and her relatives. Next-generation sequencing (NGS) was used to analyze 106 target genes by capturing the exons and adjacent intronic regions.