Antibiotic residues have drawn global attention due to its potential risks of drug resistance, allergic reactions and cancer induction. Developing highly sensitive and efficient adsorbents for the detection and adsorption of antibiotics is significantly important. Hence, a novel quantum carbon dots-doped hydrogel (CQDs-DAH) using methacryloyloxyethyltrimethyl ammonium chloride (DMC), acrylamide (AM) and carbon quantum dots (CQDs) was prepared for simultaneous detection and adsorption of sulfisoxazole (SSX). The morphological structure and chemical composition of CQDs-DAH were thoroughly characterized. Remarkably, the hydrogel exhibited excellent selectivity and sensitivity toward SSX, achieving a low detection limit of 3.5 × 10−4 mg/L and a linear detection range of 0–0.385 mg/L. Additionally, CQDs-DAH demonstrated exceptional adsorption performance in a solution with an initial SSX concentration of 50 mg/L, with a maximum capacity of 36.46 mg/g within just 20 min, following the Temkin isotherm and pseudo-second-order kinetic model. Thermodynamic analysis further revealed that the adsorption process was endothermic in nature. Furthermore, the mechanism underlying the adsorption and detection of SSX by CQDs-DAH was elucidated. CQDs-DAH offered a combination of rapid kinetics, high sensitivity, and dual functionality. This study provides valuable insights into the production of multifunctional adsorbents for the sensitive detection and efficient adsorption of SSX.

Bulk acoustic wave resonators (BAWR) and bandpass filters operating at GHz frequency are the workhorse of (Vo-)LTE telecommunication and broadband internet. In line with the Singapore Green Plan 2030 for innovating environmentally friendly products, we fabricated lead-free BAWR with sodium niobate (NaNbO3) piezoelectric on silicon with a high electromechanical coupling factor up to 31.3

ABSTRACT Quantum dots (QDs) have emerged as standout candidates among inorganic nanomaterials, distinguished by their tunable photoluminescence, exceptional photostability, and size‐dependent quantum confinement effects that enable tailored emission from the visible to the near‐infrared range. These remarkable optical properties, coupled with broad absorption spectra and high quantum yields, have positioned QDs at the forefront of diverse biomedical applications. This review provides a systematic overview of QDs fabrication strategies, with a focus on bottom‐up approaches, such as colloidal synthesis, hydrothermal, and solvothermal methods, as well as emerging biomimetic synthesis inspired by natural biomineralization. Additionally, we offer an in‐depth discussion of cutting‐edge QDs applications across three key areas: high‐sensitivity biosensing for biomarker detection and point‐of‐care diagnostics; bioimaging, including fluorescence, magnetic resonance, and photoacoustic imaging; and intelligent nanocarrier‐based cancer therapeutics, encompassing targeted drug delivery and imaging‐guided precision surgery. Furthermore, this review examines the key challenges and optimization strategies for QDs in biomedical applications, with a particular focus on the critical bottlenecks impeding their clinical translation. By analyzing these barriers and outlining future directions, it aims to provide both theoretical and practical guidance for translating QDs from laboratory‐scale innovations into routine clinical practice.

Aqueous zinc‑iodine batteries (AZIBs) represent a highly attractive technology for large-scale energy storage, yet their practical deployment is severely hindered by the concurrent challenges of zinc dendrite growth, parasitic side reactions, and the polyiodide shuttle effect. Herein, we design an electrostatic-interaction-tailored polyacrylamide-phytic acid-choline chloride (PAM-PA-ChCl) deep-eutectic gel electrolyte (DEGE) to fundamentally manipulate the interfacial microenvironment. Within this DEGE, the electrostatic shielding of choline cations (Ch+) effectively homogenizes the local Zn2+ flux to suppress dendrite proliferation, while the coordination between PA and Zn2+ optimizes deposition kinetics. Concurrently, the robust electrostatic repulsion from the phosphate anions of PA blocks polyiodide crossover, thereby eliminating the shuttle effect. Benefiting from this sophisticatedly tailored microenvironment, the DEGE enables an exceptionally stable zinc stripping/plating lifespan of up to 4000 h at 1 mA cm−2. Remarkably, the assembled AZIB full cells deliver an ultra-stable cycling performance exceeding 19,000 cycles at 10 A g−1. Furthermore, a practical high-loading pouch cell successfully achieves a high reversible capacity of 21.6 mAh after 200 cycles at 1 A g−1. This work provides an effective strategy for designing multi-functional eutectic electrolytes toward practically viable, long-life AZIBs.

The manipulation of phases in two-dimensional materials has garnered significant attention in recent years. Utilizing first-principles calculations, we investigate the crystal structures, magnetic mechanism, and electronic properties of the CrSBr bilayer in the presence of external vertical pressure. Our results demonstrate that the application of pressure leads to metallization and magnetic transition in the CrSBr bilayer. The distinct behaviors of Cr-Cr distance at low-and high-pressure induce a transition from an antiferromagnetic to a ferromagnetic state. The delocalization of electrons around Cr atoms, along with the enhanced hybridization of S and Br atoms, contributes to the metallization under pressure. The bandgap closure of the ferromagnetic CrSBr bilayer takes place at 3.9 GPa, while that of the antiferromagnetic CrSBr bilayer takes place at 5.0 GPa. Furthermore, applying pressure will markedly alter the out-of-plane magnetic anisotropy energy, resulting in a shift of the easy axis from the b axis to the c axis. This work demonstrates the control of phase transitions in the antiferromagnetic CrSBr bilayer, indicating CrSBr bilayer is a promising candidate for designing related spintronic devices.

Knowledge of the kinetics of polymerization plays a crucial role in the optimization of a synthesis process with appropriate polymerization rate and product quality. The polymerization of acryloyloxyethyl trimethyl ammonium chloride (DAC) was investigated using a dilatometer method in an aqueous solution. The impacts of temperature, monomer concentration, and initiator concentration on the polymerization rate were examined. The results showed that the polymerization rate increased with an increase in the temperature, monomer concentration, and initiator concentration. The activation energy of polymerization under the given conditions of 2.07 molL-1 DAC, 1.72 x 10-3 molL-1 ammonium persulfate, and 1.05 x 10-4 molL-1 Na4 EDTA was E a = 85.25 kJmol-1. The overall polymerization rate equation was R p = K[M]1.69[I]0.53. Based on the experimental results, the mechanism of polymerization was discussed in detail. The studies supplied the experimental basis for the industrial implementation of this reaction.

Engineering sapphire substrates with specific surface characteristics is crucial for the epitaxial growth of high-quality wafer-scale transition metal dichalcogenides, essential for integration with semiconductor industry processes. Here, we report that atomic-step-engineered sapphire surfaces undergo structural and chemical changes upon air exposure, which may be associated with surface hydrolysis and the formation of aluminum (oxy)hydroxides as revealed by a self-developed charge-contrast enhanced X-ray photoelectron spectroscopy technique. We suggest these species transform into oxygen-deficient Al2O3-x under typical growth conditions, associated with disrupted domain alignment. We further demonstrate that ultraviolet light irradiation in air appears to mitigate this degradation, restoring surface stoichiometry and promoting epitaxial alignment. The grown monolayer WS₂ films exhibit high crystalline quality, good uniformity, and low defect density. Statistical analysis of 100 field-effect transistors shows a device yield >95% and a mobility variation <20%. These findings provide relevant insights for the consistent production of industrial-scale, high-quality 2D semiconductors.

The synthesis of two-dimensional AgCr2S4 has generated significant interest in AM2X4 type non-van der Waals materials. AM2X4 monolayer breaks the central inversion symmetry of the system by intercalation, resulting in intrinsic multiferroicity. Based on recent experimental achievements of the FeS2 monolayer, we predict two intrinsic multiferroic materials: CuFe2S4 and CuFe2Se4. Utilizing first-principles calculations, we demonstrate their ferroelectric and ferromagnetic properties. Our findings indicate that strain can switch the direction of polarization due to the different displacements of the ionic center and the center of electron density. CuFe2X4 (X = S, Se) monolayers are metal with antiferromagnetic coupling in the perpendicular direction under ambient conditions. The spontaneous polarizations for CuFe2S4 and CuFe2Se4 monolayers are 1.73 and 1.42 pC/m, respectively. Applying a compressive strain exceeding 3% can reverse the polarization direction, while a tensile strain of 4% enhances the polarization of CuFe2S4 to 2.65 pC/m. In addition, the strain effectively influences the magnetic ground state, the direction of the easy axis, and the contribution of different orbital hybridization. These findings help us understand the ferromagnetic and ferroelectric mechanisms in the CuFe2X4 monolayers and expand the family of 2D multiferroic materials.

Photocatalytic degradation offers a highly efficient and ecofriendly way of removing organic pollutants such as antibiotics, from the water under visible light, though the design of effective photocatalyst remains a key challenge. In this study, a 3D new copper-based metal-organic framework (Cu-MOF), [Cu2(BPYP)(CPA)(2)center dot 2DMA] (1), was synthesized hydrothermally using camphoric acid (H(2)CPA) and 2,5-bis(pyrid-4-yl)pyridine (BPYP) as organic linkers. Structural was characterization by FT-IR spectroscopy, thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction confirmed that 1 features a paddle-wheel dinuclear Cu(II) architecture, with each Cu center adopting a distorted trigonal bipyramidal geometry. The carboxylate groups exhibit a syn-syn bridging mode between the two Cu ions. Photocatalytic studies confirmed that 1 effectively degrades trace (ppb) concentrations of various antibiotics, including oxytetracycline (OXY), secnidazole (SIZ), sulfasalazine (SLA), sulfamethoxazole (SMT), and bicalutamide (BCL), following pseudo-first-order kinetics. Under visible-light irradiation, OXY degradation reached 91.45 % within 60 min. Radical trapping examinations show that superoxide radicals (center dot O-2(-)) play a dominant role in the photocatalytic mechanism. Reusability tests confirmed the material's structural robustness and sustained catalytic performance over four successive cycles. These findings highlight the potential of 1 as an efficient and reusable photocatalyst for the removal of pharmaceutical pollutants from aqueous environments.

The synthesis of carbon quantum dots (CQDs) with high added value from a wide range of renewable biowaste sources holds utmost significance in addressing environmental and economic concerns. Herein, we present a simple and environmentally friendly method for synthesizing high-quality fluorescent nitrogen-doped CQDs (NCQDs) using orange peel. The obtained N-CQDs were employed as an efficient on-off-on fluorescent sensor for sequential ferric ions (Fe3+) and ascorbic acid (AA) detection. The linear range for the determination of Fe3+ was observed to be 2-150 mu M, with a limit of detection (LOD) of 0.253 mu M. Additionally, within the concentration range of 30-130 mu M, the recovery fluorescence exhibited a favorable linearity with the concentration of AA. The calculated LOD for this range was found to be 1.57 mu M. In addition, the prepared N-CQDs have been readily applied as information encryption. Besides, the paper based N-CQDs sensor, combined with the RGB/HSV analysis software, provides a cost-effective and portable solution for on-site fluorescence detection. To our knowledge, it is the first time that the CQDs derived from orange peel have been utilized in the domains of anticounterfeiting and smartphone-assisted portable detection. These findings highlight the significant and diverse applications of biomass-derived CQDs.

A schematic illustration of the synthesis pathway of CQDs and their application in MnO 4 − sensing based on a smartphone-assisted platform is shown.

This study investigates the influence of local defects introduced in highly oriented pyrolytic graphite (HOPG) substrates on the electronic properties of two-dimensional transition-metal dichalcogenides (TMDs). Utilizing a combination of X-ray photoelectron spectroscopy (XPS) and angle-resolved photoemission spectroscopy (ARPES), we studied the changes in energy level alignment and interface charge transfer phenomena at the HOPG/WS2 interface. While XPS did not detect significant spectral changes for defect densities up to similar to 7%, ARPES line shape analysis revealed that the increased defect density in the HOPG interfacing the WS2 monolayer significantly shortened carrier lifetimes. This provides crucial guidance for the study and optimization of devices wherein TMDs are interfaced with a HOPG or graphene.

Methyl orange is one of the most commonly used acidic/anionic dyes, and its removal from wastewater is imperative to ensure environmental sustainability. This study developed a novel cationic CQDs/AM/DMC hydrogel using acrylamide (AM) and methylacryloxyethyl trimethyl ammonium chloride (DMC) as main materials, incorporating carbon quantum dots (CQDs). The hydrogel was comprehensively characterized for morphological features, chemical composition and fluorescence characteristics using FTIR, TEM, SEM, PL and XRD analyses. Moreover, as an adsorbent, the hydrogel effectively removed methyl orange (MO) dye from aqueous solutions. Notably, the CQDs/AM/DMC hydrogel exhibited a maximum adsorption capacity of 298.93 mg/g within 30 min, surpassing that of AM/DMC hydrogel (268.29 mg/g within 50 min) in 50 mg/L MO solution. The Langmuir isotherm and pseudo-second-order models had the best agreement with the experimental data, highlighting monolayer and chemical adsorption as the predominant mechanism governing dye uptake. This study contributes valuable insights into the development of an efficient adsorbent for the removal of hazardous materials from wastewater.

Semiconducting transition metal dichalcogenides (TMDs) are a class of two-dimensional materials with potential applications in optoelectronics, spintronics, valleytronics, and quantum information processing. Understanding their stability under ambient conditions is critical for determining their in-air processability during device fabrication and for predicting their long-term device performance stability. While the effects of environmental conditions (i.e., oxygen, moisture, and light) on TMD degradation are well-acknowledged, the role of defects in driving their oxidation remains unclear. We conducted a systematic X-ray photoelectron spectroscopy study on WS2 single crystals with different surface S-vacancy concentrations formed via controlled argon sputtering. Oxidation primarily occurred at defect concentrations ≥ 10%, resulting in stoichiometric WO3 formation, while a stable surface was observed at lower concentrations. Theoretical calculations informed us that single S-vacancies do not spontaneously oxidize, while defect pairing at high vacancy concentrations facilitates O2 dissociation and subsequent oxide formation. Our XPS results also point to vacancy-related structural and electrostatic disorder as the main origin for the p-type characteristics that persists even after oxidation. Despite the complex interplay between defects and TMD oxidation processes, our work unveils scientifically informed guidance for working effectively with TMDs.

AbstractThe diverse morphologies of 2D transition metal dichalcogenides (2D TMDs) motivate their broad potential applications in the next generation of electronic, optical, and catalytic technologies. It is advantageous to develop controllable growth techniques that afford versatility through direct manipulation of the growth parameters. A fundamental understanding of the physical mechanisms driving various growth modes is crucial for achieving the process precision necessary for obtaining reproducible morphologies in 2D TMDs. Thermodynamic and kinetic considerations are two key physical strategies. Thermodynamic strategies mainly involve the manipulation of parameters like temperature and the chemical potential of precursors to ensure the thermostability of various morphologies. Conversely, kinetic strategies, focusing on the factors, like precursor diffusion, adsorption, and desorption during the growth, also enable atomic‐level kinetics control of the resulting morphologies. Often, an interplay of both mechanisms drives the growth of a particular morphology. This review aims to provide an updated guidance for exploiting these physical strategies in the versatile technique of chemical vapor deposition. The opportunities for further exploring the control of these physical mechanisms are discussed through recent examples with an eye on unlocking the untapped potential of 2D TMDs in areas such as phase engineering and shape control for advanced applications.

Self-intercalation in two-dimensional (2D) materials, converting 2D materials into ultrathin covalently bonded materials, presents great possibilities for studying a new family of quantum-confined materials with the potential to realize multifunctional behavior. However, understanding the mechanisms and associated in situ kinetics of synthesizing self-intercalated 2D (ic-2D) materials, particularly at the atomic scale, remains elusive, greatly hindering the practical applications of ic-2D crystals. Here, we successfully in situ synthesized ic-2D thin films via thermal annealing of their parental TMDCs inside an electron microscope. We atomically visualized the evolution from TaS2 and NbS2 into the corresponding ic-2D Ta1+xS2 and ic-2D Nb1+xS2, respectively, by in situ scanning transmission electron microscopy (STEM). The self-intercalation process in TaS2 is atomically realized by metal adatom edge adsorption and subsequent diffusion in an atom-by-atom manner. On the other hand, MoS2 and MoSe2 tend to coalesce into metal crystals under the same annealing conditions, suggesting that the self-intercalation process is predominantly controlled by thermodynamic factors as further verified by density functional theory (DFT). By varying the ramping rate and annealing temperature, the coverage and spatial arrangement of the filling sites can be precisely tuned, ranging from 2a × 3a, 3a × 3a, or Ta trimers, as predominantly gauged by kinetic factors. Our work sheds light on the thermodynamics and growth kinetics involved in ic-2D formation and paves the way for growing highly crystalline ic-2D materials with intercalation concentration and topology-dependent properties.

The exploration of two-dimensional (2D) intrinsic ferromagnetic materials has garnered significant attention in recent years. Most discovered 2D ferromagnets typically exhibit low Curie temperatures and unstable magnetic configurations under strain due to the competition between the direct exchange and the superexchange interaction. In this work, we apply the density functional theory to investigate the electronic structures, magnetic properties, and Curie temperatures of a single-atomic thick ferromagnet CrAs. Our findings indicate that the CrAs monolayer maintains half-metallic properties and a stable ferromagnetic state over a wide strain range of -10% to 10%. The Heisenberg exchange parameter J(1) can be regulated linearly from 28 to 51 meV. Furthermore, the Monte Carlo simulations demonstrate that the Curie temperature of the CrAs monolayer (942 K) is much higher than room temperature. These intriguing electronic and magnetic properties reveal that CrAs is a promising candidate for various spintronic devices.

Broadband, energy-efficient signal transfer between a cryogenic and room-temperature environment has been a major bottleneck for superconducting quantum and classical logic circuits. Photonic links promise to overcome this challenge by offering simultaneous high bandwidth and low thermal load. However, the development of cryogenic electro-optic modulators—a key component for the photonic readout of electrical signals—has been stifled by the stringent requirements of superconducting circuits. Rapid single-flux-quantum circuits, for example, operate with a tiny signal amplitude of only a few millivolts, far below the volt-level signal used in conventional circuits. Here we demonstrate one of the first direct optical readouts of a rapid single-flux-quantum circuit without additional electrical amplification enabled by a novel superconducting electro-optic modulator featuring a record-low half-wave voltage V π of 42 mV on a 1-m-long superconducting electro-optic modulator. Leveraging the low ohmic loss of superconductors, we break the fundamental V π –bandwidth trade-off and demonstrate an electro-optic bandwidth up to 17 GHz on a 0.2-m-long superconducting electro-optic modulator at cryogenic temperatures. Our work presents a viable solution towards high-bandwidth signal transfer between future large-scale superconducting circuits and room-temperature electronics.

Prussian blue (PB), a representative metal-organic framework, holds great promise as an electrode material for optical applications. However, the preparation of cycle-stable PB with minimal defects/vacancies and coordinated water has been limited by the uncontrollable growth kinetics. Here, we report on the electrodeposition of a cycle-stable PB film via presilanization on the growth substrate. By self-assembling an aminosilane layer on the indium-tin oxide (a-ITO) substrate before the PB growth, we demonstrate an a-ITO/PB film with minimal defects/vacancies and water (similar to 5%), as validated by a combination of X-ray photoelectron spectroscopy (XPS), Raman and thermogravimetric analysis (TGA) studies. In addition, scanning electron microscopy (SEM) measurements indicate that the conventional delamination and cracking issue of the PB film can be effectively impeded in our a-ITO/PB film over 1000 cycles. The cyclic tests also indicate that the a-ITO/PB film attains a remarkably higher charge density of 17.4 mC/cm2 with better stability (charge density retention similar to 87% over 1000 cycles) than the state-of-the-art PB benchmark. The crucial role of the aminosilane treatment in increasing the a-ITO/PB interaction/binding is elucidated by density functional theory (DFT) simulations. DFT results suggest that there is a substantial charge redistribution localized around the interface of a-ITO/PB, leading to six times increment in binding energy as compared to non-treated ITO/PB. As an exemplified application, the cycle-stable a-ITO/PB film is applied as an efficient counter electrode in a smart glass. This study paves an effective interfacial engineering means for increasing the binding at the PB-substrate interface and structural integrity of PB itself for long-term electrochemical and optical applications.