Browse Articles

Synergistic Self‐Assembled Monolayers Reinforce Buried Interface Anchoring for High‐Efficiency Tandem Perovskite Solar Cells

Abstract Carbazole‐based self‐assembled monolayers (SAMs) have been commonly used as a single‐component hole transport layer (HTL) in inverted perovskite solar cells (PSCs), but suffer from facile π‐π stacking and self‐aggregations in solution and consequently poor anchoring ability with the atop perovskite layer. Herein, we developed a synergistic SAM (syn‐SAM) strategy through blending a non‐planar molecule 3,3‐(4‐amino‐4H‐1,2,4‐triazole‐3,5‐diyl)‐dibenzo acid (ABT) bearing multiple anchoring sites with the commonly used Me‐4PACz SAM. The coexistence of these two components leverages π‐π interactions and hydrogen bonding to mitigate aggregation effects, affording dense and uniform SAM, thereby enhancing anchoring at the perovskite buried interface and alleviating interfacial charge recombination. ABT incorporation further helps to mitigating tensile strain in perovskite film. Additionally, this strategy offers advantages of multi‐device compatibility. The single‐junction champion inverted PSC devices based on syn‐SAM deliver power conversion efficiencies (PCEs) of 25.75% (certified 25.45%) and 22.76% (area: 0.105 cm 2 ) for 1.56  and 1.68 eV bandgap perovskites, respectively. Moreover, this approach is beneficial for the monolithic perovskite/silicon tandem solar cells based on fully textured surfaces of heterojunction (HJT) silicon bottom cells, affording PCEs of 31.56% (area: 1.07 cm 2 ) and 26.57% (area: 20.06 cm 2 ). All devices exhibit excellent long‐term storage and thermal stability even under non‐encapsulated conditions.

The Notch ligand Jagged1 plays a dual role in cochlear hair cell regeneration

Experimental study of Fabry–Pérot BICs in a microwave waveguide

We study Fabry–Pérot bound states in the continuum (FP-BIC) in the GHz frequency range in a metal-walled rectangular waveguide with two ceramic disks placed inside it. The disks act as perfect reflectors at the resonance frequency, and the energy becomes perfectly trapped between the disks, forming an FP-BIC when the distance between them satisfies the Fabry–Pérot quantization condition. We investigate the system both theoretically and experimentally, revealing how the total and radiative quality (Q) factor depends on the inter-disk distance. We gain valuable insights into the Fano features observed in the transmission spectra using the quasi-normal mode technique and temporal coupled-mode theory. Notably, we find that as the system approaches the BICs, the Fano asymmetry parameters diverge, resulting in a Lorentzian peak in the transmission spectrum. The experimentally measured radiative Q factor is on the order of 105, while the total Q factor, limited by material losses, remains around 103. These results open up new possibilities for utilizing BICs in microwave technology, with the potential to significantly enhance the performance of microwave devices.

Near-global spawning strategies of large pelagic fish

Erratum: “Strain dependence of Auger recombination in 3  <b> <i>μ</i> </b> m GaInAsSb/GaSb type-I active regions” [Appl. Phys. Lett. <b>116</b> , 262103 (2020)]

Photonic terahertz phased array via selective excitation of nonlinear Pancharatnam-Berry elements

Abstract Phased arrays are crucial in various technologies, such as radar and wireless communications, due to their ability to precisely control and steer electromagnetic waves. This precise control improves signal processing and enhances imaging performance. However, extending phased arrays to the terahertz (THz) frequency range has proven challenging, especially for high-frequency operation, broadband performance, two-dimensional (2D) phase control with large antenna arrays, and flexible phase modulation. Here, we introduce a photonic platform to realize a THz phased array that bypasses the above challenges. Our method employs 2D phase coding with 2-bit across a broad THz frequency range from 0.8 to 1.4 THz. The core of our design is a pixelated nonlinear Pancharatnam-Berry (PB) metasurface driven by a spatially modulated femtosecond laser for selective excitation of the desired PB elements, allowing precise phase and wavefront control of the emitted THz signals. We showcase the effectiveness of our method through four proof-of-concept applications: single beamforming, dual beamforming, imaging, and vortex beam generation. The realized photonic platform provides a promising pathway for developing broadband phased arrays in the THz regime.

Metalloenzyme‐Catalyzed Asymmetric Transfer Hydrogenation for the Synthesis of Chiral Amines

Abstract Chiral amines are prevalent in natural products, pharmaceuticals, and organic catalysts. Their increasing demand has driven the advancement of synthetic methods. In this study, we developed a metalloenzyme‐catalyzed asymmetric transfer hydrogenation method for the synthesis of chiral amines. Given the challenges of traditional chemical synthesis, which relies on precious metals and complex synthetic ligands, our approach utilizes base metals derived from natural metalloenzymes for transfer hydrogenation and employs protein scaffolds to achieve stereochemical control. Furthermore, in contrast to natural NAD(P)H‐dependent C═N bond reductases, this strategy utilizes silanes as reducing agents and is entirely orthogonal to conventional NAD(P)H‐dependent cellular functions. This reactivity highlights the potential to develop new‐to‐nature enzymatic functions capable of addressing challenges in both organic synthesis and biosynthesis.

Continuously tunable uniaxial strain engineering of two-dimensional materials under scanning probe microscopy

Uniaxial strain has emerged as a powerful technique for manipulating quantum phenomena in van der Waals (vdW) materials. However, most existing strain-engineering approaches face critical limitations: (i) incompatibility with real-time nanoscale characterization, (ii) restricted maximum strain, and (iii) discontinuous strain application. To overcome these challenges, we develop NanoGap, a piezoelectric-driven strain platform that achieves full compatibility with scanning probe microscopy (SPM) techniques while enabling continuous strain in multilayer vdW crystals. Applying this methodology to hexagonal boron nitride flakes (20–50 nm thickness), we achieve 1.2% uniaxial tensile strain, as quantified through in situ atomic force microscopy measurements. Moreover, our strain-SPM integration reveals the direct correlation between progressive lattice deformation and phonon polariton dispersion alterations, as demonstrated through photo-induced force microscopy. This synergistic methodology establishes a paradigm for strain engineering by enabling simultaneous real-time nanoscale characterization and continuous strain manipulation.

Mature and migratory dendritic cells promote immune infiltration and response to anti-PD-1 checkpoint blockade in metastatic melanoma

Abstract Immune checkpoint inhibitors (ICIs) have revolutionized cancer therapy, yet most patients fail to achieve durable responses. To better understand the tumor microenvironment (TME), we analyze single-cell RNA-seq (~189 K cells) from 36 metastatic melanoma samples, defining 14 cell types, 55 subtypes, and 15 transcriptional hallmarks of malignant cells. Correlations between cell subtype proportions reveal six distinct clusters, with a mature dendritic cell subtype enriched in immunoregulatory molecules (mregDC) linked to naive T and B cells. Importantly, mregDC abundance predicts progression-free survival (PFS) with ICIs and other therapies, especially when combined with the TCF7 + /– CD8 T cell ratio. Analysis of an independent cohort (n = 318) validates mregDC as a predictive biomarker for anti-CTLA-4 plus anti-PD-1 therapies. Further characterization of mregDCs versus conventional dendritic cells (cDC1/cDC2) highlights their unique transcriptional, epigenetic (single-nucleus ATAC-seq data for cDCs from 14 matched samples), and interaction profiles, offering new insights for improving immunotherapy response and guiding future combination treatments.

A C‐to‐B Atom Swap on Coumarins and Dibenzolactones

Abstract We report a carbon‐to‐boron “C‐to‐B” atom swap reaction to transform readily available coumarins into their isosteric benzoxaborins via a net replacement of the C═O group with a B─OH moiety. These conditions were applied to coumarin natural products and other 6–7‐membered lactones (25 examples, 29%–93%). We leverage this methodology to transform a flat polyaromatic hydrocarbon into three‐dimensional tribenzo[b.d.f]oxepines through a series of atom‐swapping reactions followed by ring expansion via the oxaborin intermediate.

A universal approach: Nanodiamond mediated reduction of Co nanoparticle exsolution from La0.7Sr0.2Fe0.8Co0.2O3 for enhanced oxygen evolution reaction

The in situ exsolution process for metallic Co is crucial for developing low-cost and efficient oxygen evolution reaction (OER) catalysts based on perovskite materials. However, traditional exsolution methods normally require working in a hydrogen-reducing atmosphere. To address these limitations, by introducing nanodiamond (ND) into La0.7Sr0.2Fe0.8Co0.2O3 (LSFC), Co nanoparticles (NPs) were exsolved on the surface after thermal treatment. Owing to the unique sp2/sp3 hybrid structure of ND, the electron transfer at high temperature enhances the electron density on the ND surface, creating a reducing environment for the exsolution of Co NPs. The electrocatalyst exhibits significantly reduced overpotentials (265 mV at 10 mA cm−2 and 327 mV at 100 mA cm−2), a small Tafel slope of 52.14 mV dec−1, and good stability (88.9% of initial current density after a chronoamperometric durability test). This enhancement primarily results from the exsolution of Co NPs, which increases the number of active sites. Density functional theory calculations explain the role of ND in improving OER performance. This approach holds great promise for innovating various energy storage and conversion technologies.

Application of new approach methodologies for nonclinical safety assessment of drug candidates

Aerosol iodide accelerates reactive nitrogen cycling in the marine atmosphere

The Overlooked Dual Phosphorescence of Lappert's Diamino Stannylene Sn[N(SiMe ₃ ) ₂ ] ₂

Abstract The first stable heavy carbene homologues, the heavy tetrylenes, were reported in 1973 by Lappert and coworkers. These tetrylenes were extensively investigated with respect to ground state reactivity, such as small molecule activation, insertion into σ‐bonds, coordination chemistry, materials chemistry, or catalysis. Their photophysical properties remained essentially unexplored. We report that the bright yellow‐colored diamino stannylene Sn[N(SiMe 3 ) 2 ] 2 shows thermally activated dual orange/green phosphorescence with microsecond lifetime in fluid solution at room temperature, which has been overlooked for more than 50 years. These unique electronic and photophysical properties are studied in detail by temperature‐dependent time‐resolved emission and absorption spectroscopy and are corroborated by (time‐dependent) density functional theory (DFT) calculations. The mechanism of photochemical radical formation has been disclosed, involving unprecedented stannylene excimers with second‐order Jahn–Teller distorted structures. The present study provides new insights toward a rational design of tetrel(II) complexes with long‐lived emissive excited states, with Sn[N(SiMe 3 ) 2 ] 2 being the prototype.

Multi-order optical differentiator integrated with an omnidirectionally selective subtracter

Optical computing offers high-speed, low-power data processing, while optical differentiation enables instant edge detection for applications like autonomous driving, object recognition, and bio-detection. Introducing an extra algorithm to optical differentiation will further extend its functionality. Here, we integrate an omnidirectional subtracter with a multi-order optical differentiator via combining distinct spiral lens phases with deflection phases. With this design, zeroth-, first-, and second-order differentiations are spatially separated, and the local linear polarization always orients toward the normal of optical edges for linearly polarized incidence. Thereby, selective edge subtractions can be carried out through simply rotating a polarizer. The design is verified in a photopatterned liquid crystal, whose electro-optical tunability enables a broadband operation across the entire visible spectrum. Rotating a polarizer confirms omnidirectional edge extraction in first- and second-order differentiations while preserving the zeroth-order bright field imaging. The direction-selective defect suppression enhances applications like rainy-day autonomous driving and object recognition in directional noise. This work advances optical differentiation, enabling high-performance edge-sensitive imaging.

High-fidelity Cas9-mediated targeting of KRAS driver mutations restrains lung cancer in preclinical models

Abstract Missense mutations in the 12th codon of KRAS are key drivers of lung cancer, with glycine-to-cysteine (G12C) and glycine-to-aspartic acid (G12D) substitutions being among the most prevalent. These mutations are strongly associated with poor survival outcomes. Given the critical role of KRAS in lung cancer and other cancers, it remains as a major target for the development of new and complementary treatments. We have developed a CRISPR-High Fidelity (HiFi)-Cas9-based therapy strategy that can effectively and specifically target KRAS G12C and KRAS G12D mutants, avoiding KRAS WT off-targeting and affecting KRAS downstream pathways, thereby significantly reducing tumorgenicity. The delivery of HiFiCas9 components via ribonucleoprotein particles (RNPs) and adenovirus (AdV) effectively abrogates cell viability in KRAS-mutant Non-Small Cell Lung Cancer (NSCLC) preclinical models, including 2D and 3D cell cultures, cell-derived xenografts (CDX), and patient-derived xenograft organoids (PDXO). Our in vitro studies demonstrate that HiFiCas9-based therapy achieves superior KRAS inhibition compared to Sotorasib and effectively circumvents certain resistance mechanisms associated with Sotorasib treatment. Moreover, in vivo delivery using adenoviral particles significantly suppresses tumor growth in preclinical NSCLC models. Collectively, our findings establish HiFiCas9 as an effective therapeutic strategy with promising clinical applications, especially if in vivo delivery methods are further optimized.

Control of magnetic transition, metal–semiconductor transition, and magnetic anisotropy in noncentrosymmetric monolayer Cr2Ge2Se3Te3

Recent advances in two-dimensional materials have greatly expanded the family of ferromagnetic materials. The well-known 2D ferromagnets, such as CrI3, Cr2Ge2Te6, and Fe3GeTe2 monolayers, are characterized by centrosymmetric crystal structures. In contrast, ferromagnetic ordering in 2D noncentrosymmetric materials remains an underexplored area. Here, we report a Janus ferromagnet, Cr2Ge2Se3Te3 with inversion symmetry breaking, through first-principles calculations. This monolayer can undergo a ferromagnetic–antiferromagnetic transformation and a metal–semiconductor transition under different strains. Additionally, the strength of magnetocrystalline anisotropy energy (MAE) can be modulated by electric field or strain. In particular, the magnetization easy axis can be altered from in-plane to out-of-plane under strain. We find that Te3 atoms play a key role in determining the MAE, where contributions are primarily from pz/py and px/py orbitals. This study of Janus ferromagnetic materials has provided a promising platform for the research on the control of magnetism by strain or electric field.

Transboundary conflict from surface water scarcity under climate change

Revealing Parallel Inter‐ and Intra‐Ligand Charge Transfer Dynamics in [Ru(L) ₂ (dppz)] ²⁺ Molecular Lightswitch with N K‐Edge X‐Ray Absorption Spectroscopy

Abstract In photoactive metal complexes the localization of photoexcited charges dictates the site of chemical reactivity, but few studies measure the charge redistribution in these systems with spatial precision. Herein, we track the inter‐ and intra‐ligand charge transfer processes that underpin light‐driven charge separation in the well‐studied “molecular lightswitch” [Ru(bpy) 2 dppz] 2+ (aqueous [Ruthenium II (2,2′‐bipyridine)2(dipyrido[3,2‐a:2′,3′‐c]phenazine)] 2+ [Cl − ] 2 ) by probing the electronic structure of ligand nitrogen atoms in real‐time using ultrafast X‐ray absorption spectroscopy and first principles calculations. We confirm the localization of excited electron density on the phenazine N atoms of dppz and we newly identify two parallel electron transfer pathways to populate this state. Sub‐70 fs electron transfer to the phenazine portion of dppz is observed and attributed to intra‐ligand electron transfer following Ru‐to‐dppz metal‐to‐ligand charge transfer (MLCT) excitation. This fast charge transfer was not reported in prior ultrafast studies. The slower (ca. 2 ps) charge transfer reported extensively in time‐resolved optical absorption and emission studies is reassigned here to inter‐ligand electron “hopping” between nearly isoenergetic ligand moieties following Ru‐to‐bpy MLCT excitation. The results demonstrate much faster charge separation than previously identified in this well‐studied system, highlighting how extended azaacene ligand motifs promote the competitive charge transfer processes needed to drive light‐driven electron transfer chemistry.

Electron beam-induced reduction of Schottky barrier width for low contact resistance molybdenum disulfide field-effect transistor

In order to address the issue of the substantial contact resistance commonly encountered at the metal and two-dimensional (2D) semiconductors, an approach involving the reduction of Schottky barrier width by electron beam-induced defects has been demonstrated. Molybdenum disulfide (MoS2) field-effect transistors (FETs) demonstrate notable enhancements in their performance after electron beam irradiation (EBI) of the contact regions. Systematic studies revealed an optimal relationship between EBI dose and MoS2 layer thickness, with field-effect mobility (μEF) as a key metric. Under an accelerating voltage of 20 kV and an irradiation dose of 600 µC/cm2, 7 nm thick MoS2 FETs achieved a μFE exceeding 150 cm2/V s, representing a tenfold improvement over untreated devices, while contact resistance decreased significantly to 1.4 kΩ µm, an order of magnitude reduction. The observed performance improvement is attributed to EBI-induced sulfur vacancies, which narrow the Schottky barrier width by approximately 45% and enhance electron injection efficiency. The results highlight that EBI-induced defect engineering is a promising method for optimizing electrical performance in 2D-based FETs.