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The spontaneous exchange bias effect (SEB) has wide application prospects in information storage technologies. In this study, nanoscale raw materials were used to fabricate antiferromagnetic Fe3BO6 polycrystals. The obtained Fe3BO6 exhibited a large SEB effect, where the value of the spontaneous exchange bias field at room temperature was as large as ∼4234 Oe. The room-temperature training effect, temperature-dependence, and maximum field-dependence of the HSEB were investigated. We propose that this giant SEB originates from the exchange-coupling interactions between the weak ferromagnetic surface state and the bulk antiferromagnetic state. The theoretical analysis results were further verified by comparing the magnetic properties of the Fe3BO6 with relatively low crystallinity. The results of this investigation will help find promising candidate materials for devices based on the SEB effect. [ABSTRACT FROM AUTHOR]

The in situ growth dynamics of colloidal silver–gold core–shell (Ag@Au CS) nanoparticles (NPs) are studied using time-dependent second harmonic generation (SHG) and extinction spectroscopy. Four sequential additions of chloroauric acid, sodium citrate, and hydroquinone are added to a silver nanoparticle solution to form a gold shell around a 45 nm silver core under different reaction conditions, resulting in final sizes ranging from 80 to 125 nm in diameter. In the first addition, a bumpy, urchin-like surface morphology is produced, while the second, third, and fourth additions provide additional nanoparticle growth with the surface morphology becoming more smooth and uniform, as shown using transmission electron microscopy measurements. The in situ extinction spectra increase in intensity for each addition, where blue-shifting and spectral narrowing are observed as the Ag@Au CS NPs grow in size. The extinction spectra are compared to Mie theory simulations, showing general agreement at later stages of the reactions for smooth CS surfaces. The in situ SHG signal is dominated by surface-enhanced plasmonic hotspots at the early stages of the shell growth, followed by gradual decreases in signal as the surface becomes more smooth. Two-photon fluorescence is also monitored during the CS growth, showing complementary information for comparisons to the extinction and SHG results. The holistic study of the synthesis and characterization of Ag@Au CS nanoparticles using in situ SHG spectroscopy, extinction spectroscopy, and Mie theory simulations allows for a comprehensive analysis of the complex growth dynamics occurring at the nanoscale for developing optimized plasmonic nanomaterial properties. [ABSTRACT FROM AUTHOR]

We investigate the MX2 (M = {Hf, Zr}, X = {S, Se}) transition metal dichalcogenides patterned into armchair (AC) and zigzag (ZZ) nanoribbons (NRs) as potential channel materials in future logic field-effect devices. Ab initio quantum transport simulations are employed to assess the electronic, transport, and ballistic field-effect transistor (FET) properties of devices with such quasi-one-dimensional channels. We report a non-monotonic scaling behavior of MX2NR properties due to strong quantum confinement effects, which is reflected in a strong dependence of the ON-state current (ION) of MX2NR FETs on the nanoribbon configuration. The ∼2 nm-wide HfSe2 and ZrSe2 AC-PFETs have the highest ION of up to 2.6 mA/μm at 10 nA/μm OFF-state current. Surprisingly, MX2NR ZZ-NFETs exhibit a current increase of up to 70% when channel width is scaled down, with ION reaching 2.2 mA/μm in ∼2 nm-wide devices. The high ON-state performance is a direct consequence of high carrier injection velocity, which is explained by analyzing the band structure, transmission, and density of states. We demonstrate that nanostructured MX2 materials can be promising candidates for future logic transistors based on multi-nanowire architectures. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) reduced graphene oxide (rGO)/Ti2CTx MXene hybrid aerogels were effectively prepared by a two-step method involving hydrothermal reaction and freeze-drying. The intimately coupled rGO/Ti2CTx hybrid aerogel combined high electrical conductivity, large interlayer spacing, and excellent mechanical stability of Ti2CTx, which not only effectively prevents the self-restacking of Ti2CTx nanosheets, exposes more active sites exposed, and improves the volume change during the charge/discharge process but also increases the accessibility of ions and promotes the rapid transfer of ions/electrons. As a result, rGO/Ti2CTx 17.5–2.5 as the working electrode of electric double layer capacitors delivers a large specific capacity (107.05 F g−1 at 0.5 A g−1 in a 1M Na2SO4 electrolyte), a high rate capability (maintains 30% of its initial capacitance at 10 A g−1, which is much better than rGO and Ti2CTx), and excellent long-term large-current cycle stability (the initial capacitance remains above 71.1% after 10 000 cycles at 1 A g−1). In addition to providing a high-performance electrode for supercapacitors, this study proposes an efficient and time-saving strategy for constructing 3D structures from 2D materials. [ABSTRACT FROM AUTHOR]

In the liquid phase of heterogeneous catalysis, solvent plays an important role and governs the kinetics and thermodynamics of a reaction. Although it is often difficult to quantify the role of the solvent, it becomes particularly challenging when a zeolite is used as the catalyst. This difficulty arises from the complex nature of the liquid/zeolite interface and the different solvation environments around catalytically active sites. Here, we use ab initio molecular dynamics simulations to probe the local solvation structure and dynamics of methanol and water over MWW zeolite nanosheets with varying Brønsted acidity. We find that the zeolite framework and the number and location of the acid sites in the zeolite influence the structure and dynamics of the solvent. In particular, methanol is more likely to be in the vicinity of the aluminum (Al3+) at the T4 site than at T1 due to easy accessibility. The methanol oxygen binds strongly to the Al at the T4 site, weakening the Al–O for the bridging acid site, which results in the formation of the silanol group, significantly reducing the acidity of the site. The behavior of methanol is in direct contrast to that of water, where protons can easily propagate from the zeolite to the solvent molecules regardless of the acid site location. Our work provides molecular-level insights into how solvent interacts with zeolite surfaces, leading to an improved understanding of the catalytic site in the MWW zeolite nanosheet. [ABSTRACT FROM AUTHOR]

The acid-resistant tungsten trioxide photoelectrochemical solid–liquid ultraviolet (UV) photodetector uses a thin film of tungsten trioxide as the photoelectrode, forming a stable heterojunction with the electrolyte. This study employed band theory and double electron layer theory to analyze the mechanisms underlying the effect of pH on the redox potential and photocurrent, utilizing the ion product constant of water and the Nernst equation. By applying the principles of energy band theory and the two-electron layer model, the electron transfer process was analyzed and explained. These findings hold significant promise for enhancing solid–liquid heterojunction UV photodetectors. Tungsten trioxide has fast response and high sensitivity under extreme conditions. The device performance of WO3 nanosheets fabricated by annealing at 300 °C for one hour is excellent, including a rise time of 0.7 s, decay time of 6.8 s, photosensitivity of 1.90, and photoresponsivity of 2.31 mA/W. 0.5M sulfuric acid produced the highest photocurrent (5.46 μA) and sensitivity (14.07). This material has potential applications in optoelectronics, catalysis, sensing, water treatment, and air purification. [ABSTRACT FROM AUTHOR]

Surface tension and interfacial tension are crucial to the study of nanomaterials. Herein, we report a solubility method using magnesium oxide nanoparticles of different radii (1.8–105.0 nm, MgO NPs) dissolved in pure water as a targeted model; the surface tension and interfacial tension (and their temperature coefficients) were determined by measuring electrical conductivity and combined with the principle of the electrochemical equilibrium method, and the problem of particle size dependence is discussed. Encouragingly, this method can also be used to determine the ionic (atomic or molecular) radius and Tolman length of nanomaterials. This research results disclose that surface/interfacial tension and their temperature coefficients have a significant relationship with particle size. Surface/interfacial tension decreases rapidly with a radius <10 nm (while the temperature coefficients are opposite), while for a radius >10 nm, the effect is minimal. Especially, it is proven that the value of Tolman length is positive, the effect of particle size on Tolman length is consistent with the surface/interfacial tension, and the Tolman length of the bulk does not change much in the temperature range. This work initiates a new era for reliable determination of surface/interfacial tension, their temperature coefficients, ionic radius, and Tolman length of nanomaterials and provides an important theoretical basis for the development and application of various nanomaterials. [ABSTRACT FROM AUTHOR]

Magic-sized nanocrystals (MSNCs) grow via jumps between very specific sizes. This discrete growth is a possible avenue toward monodisperse nanomaterials that are completely identical in size and shape. In spite of this potential, MSNCs have seen limited study and application due to their poor optical properties. Specifically, MSNCs are limited in their range of emission wavelengths and commonly exhibit poor photoluminescence quantum yields (PLQYs). Here, we report silver doping of CdSe MSNCs as a strategy to improve the optical properties of MSNCs. Silver doping leads to controllable shifts in emission wavelength and significant increases in MSNC PLQYs. These results suggest that doped MSNCs are interesting candidates for displays or luminescent solar concentrators. Finally, we demonstrate that the doping process does not affect the magic size of our MSNCs, allowing further photophysical study of this class of nanomaterial. [ABSTRACT FROM AUTHOR]

Gallenene is a novel metallic 2D material that can provide a semiconducting counterpart if patterned into quasi-one-dimensional (quasi-1D) nanostructures, i.e., gallenene nanoribbons (GaNRs). We investigate semiconducting GaNRs as a potential channel material for future ultrascaled field-effect transistors (FETs) by employing quantum transport simulations based on Green's functions and tight-binding Hamiltonians with the orbital resolution calibrated on ab initio calculations. The impact of GaNR width downscaling from ∼6 nm down to ∼0.2 nm on the electronic, transport, and ballistic device properties is investigated for the FET channel length of 15 nm. We report current enhancement and injection velocity overshoot effects for sub-1.2 nm-wide nFETs and pFETs, with a maximum current increase of 53% in the 1.2 nm-wide GaNR pFET in comparison to the widest device. In addition, promising current-driving capabilities of n- and p-channel GaNR FETs are observed with top ballistic currents of more than 2.2 mA/μm and injection velocities of up to 2.4 × 107 cm/s. The reported data are explained by analyzing the evolution of band structure and related parameters such as injection velocity, quantum capacitance, effective transport mass etc., with increasing quantum confinement effects in ultranarrow GaNRs. Generally, we find that quasi-1D gallenene is a promising channel material for future nanoscale FETs, especially for transistor architectures based on stacked nanosheets. [ABSTRACT FROM AUTHOR]

The intrinsically low electrical conductivity and poor structural fragility of MnO2 have significantly hampered the zinc storage performance. In this work, Ba2+-implanted δ-MnO2 nanosheets have been hydrothermally grown on a carbon cloth (Ba–MnO2@CC) as an extremely stable and efficient cathode material of aqueous zinc-ion batteries. The three-dimensionally porous architecture composed of interwoven thin MnO2 nanosheets effectively shortens the electron/ion transport distances, enlarges the electrode/electrolyte contact area, and increases the active sites for the electrochemical reaction. Meanwhile, Ba2+ could function as an interlayer pillar to stabilize the crystal structure of MnO2. Consequently, the as-optimized Ba–MnO2@CC exhibits remarkable Zn2+ storage capabilities, such as a high capacity (305 mAh g−1 at 0.2 A g−1), prolonged lifespan (95% retention after a 200-cycling test), and superb rate capability. The binder-free cathode is also applicable for flexible energy storage devices with attractive properties. The present investigation provides important insights into designing advanced cathode materials toward wearable electronics. [ABSTRACT FROM AUTHOR]

Nanomaterials have excellent adsorption performance due to nano-effect and have been widely used in many fields. The adsorption performance of nanomaterials depends on their adsorption thermodynamics and kinetics. Here, the thermodynamic and kinetic equations of adsorption for spherical nanoparticles are first derived in theory. The mechanisms and regularities of influences of nano-effect on thermodynamics and kinetics, using nano-CdS adsorption of methylene blue as a probe, were investigated. The results show that there are significant influences of nano-effect (i.e., interface area effect and interface tension effect) on the thermodynamics and kinetics of nanoparticle adsorption. When the particle radius is larger and beyond the nanometer scale (∼100 nm), the nano-effect can be neglected. When the radius of the nanoparticle is within 10–50 nm, the nano-effect of adsorption is mainly the interface area effect. When the radius is less than 10 nm, the influences of both the interface area effect and the interface tension effect on adsorption thermodynamics and kinetics become more significant. The theoretic equations and experimental insights in the present work could provide a significant basis and reference for improving and perfecting the adsorption theory involving nanomaterials and provide guidelines for the explanations of adsorption mechanisms as well as the selection of adsorbents. [ABSTRACT FROM AUTHOR]

Understanding interparticle interactions has been one of the most important topics of research in the field of micro/nanoscale materials. Many significant characteristics of such materials directly stem from the way their building blocks interact with each other. In this work, we investigate the efficacy of a specific category of Machine Learning (ML) methods known as interaction networks in predicting interparticle interactions within colloidal systems. We introduce and study Local Neighborhood Graph Neural Networks (LN-GNNs), defined according to the local environment of colloidal particles derived from particle trajectory data. The LN-GNN framework is trained for unique categories of particle neighborhood environments in order to predict interparticle interactions. We compare the performance of the LN-GNN to a baseline interaction network with a simpler architecture and to an Instance-Based ML algorithm, which is computationally more expensive. We find that the prediction performance of LN-GNN measured as an average normalized mean absolute error outperforms the baseline interaction network by a factor of 2–10 for different local neighborhood configurations. Furthermore, LN-GNN's performance turns out to be very comparable to the instance-based ML framework while being an order of magnitude less expensive in terms of the required computation time. The results of this work can provide the foundations for establishing accurate models of colloidal particle interactions that are derived from real particle trajectory data. [ABSTRACT FROM AUTHOR]

Two-dimensional transition metal dichalcogenides and semiconductor metal oxides have shown great potential in photocatalysis. However, their stability and efficiency need to be further improved. In this paper, porous ZnO nanorods with high specific surface area were prepared from metal-organic framework ZIF-8 by a simple hydrothermal method. A MoS2/ZnO composite was constructed by loading MoS2 onto the surface of porous ZnO nanorods. Compared with ZnO materials prepared by other methods, MoS2/ZnO prepared in this paper exhibits superior photocatalytic performance. The enhanced photocatalytic activity of the MoS2/ZnO composite can be attributed to the formation of heterojunctions and strong interaction between them, which greatly facilitate the separation of electrons and holes at the contact interface. In addition, due to the wide absorption region of the visible spectrum, MoS2 can greatly broaden the light absorption range of the material after the formation of the composite material, increase the utilization rate of visible light, and reduce the combination of electrons and holes. This study provides a new way to prepare cheap and efficient photocatalysts. [ABSTRACT FROM AUTHOR]

As the channel lengths of electronic devices are scaled down to the nanometer range, the conventional methods to evaluate charge-carrier mobility approach a technical limit that is imposed by interfering effects of the electrode and forcing field. In this study, we demonstrate that electron spectroscopy provides additional (yet hidden) information on unipolar charge transport, which is free from conventional problems. We demonstrate that the estimated effective diffusion current through the target sample allows the measurement that is precise enough (10−4 cm2/V s) to obtain the mobility of electrons μelectron and holes μhole in nanolength organic channels. Using this method, we show how μelectron and μhole are correlated with the local structural order of poly(3-hexylthiophene) at the nanoscale. This method enables in situ charge-resolved observations of μelectron and μhole by eliminating the need for electrode and forcing field and will help to expand our understanding of charge conduction in nanoscale materials. [ABSTRACT FROM AUTHOR]

The study of van der Waals (vdW) materials has seen increased interest in recent years due to the wide range of uses for these materials because of their unique mechanical, electronic, and optical properties. This area has recently expanded further into studying the behavior of vdW nanomaterials as decreasing dimensions open up opportunities to interact with these materials in new ways. However, measuring the band structures of nanomaterials, which is key to understanding how confinement affects material properties and interactions, comes with several challenges. In this review, we survey a range of techniques for synthesizing and characterizing vdW nanomaterials, in order to outline the key material and characterization challenges. This includes controlling the Fermi level in vdW nanoparticles, preparing these particles for either ensemble or individual particle measurement, as well as protecting the pristine surface from oxidation. [ABSTRACT FROM AUTHOR]

Nanosheets of transition metal dichalcogenides with prospects of photocatalysis and optoelectronics applications have significant potential in device fabrication due to their low-cost production and easily controllable morphology. Here, non-degenerate pump-probe differential transmission studies with varying pump-fluence have been carried out on single-phase 2H–MoSe2 and mixed-phase 1T/2H–MoSe2 nanosheets to characterize their excited carrier dynamics. For both the samples, the differential probe transmission data show photo-induced bleaching at earlier pump-probe delay followed by photo-induced absorption unveiling signatures of exciton-state filling, exciton trapping, defect-mediated photo-induced probe absorption and recombination of defect bound excitons. The exciton trapping and photo-induced absorption by the trapped-carriers are estimated to occur with time constant of ∼430 to 500 fs based on multi-exponential modelling of the differential transmission till pump-probe delay of ∼3.5 ps. Biexponential modeling of the subsequent slow-recovery of the negative differential transmission at pump-probe delay ≳3.5 ps reveals that the exciton recombination happens via two distinct decay channels with ∼25 to 55 ps (τ1) and ≳1 ns (τ2) time constants. Pump-fluence dependent reduction in τ1 and further modelling of exciton population using higher order kinetic rate equation reveals that the two-body exciton-exciton annihilation governs the exciton recombination initially with a decay rate of ∼ 10 − 8 cm3s−1. The detailed analysis suggests that the fraction of total excitons that decay via long decay channel decreases with increasing exciton density for 2H–MoSe2, in contrast to 1T/2H–MoSe2 where the fraction of excitons decaying via long decay channel remains constant. [ABSTRACT FROM AUTHOR]

Nanosheets of transition metal dichalcogenides with prospects of photocatalysis and optoelectronics applications have significant potential in device fabrication due to their low-cost production and easily controllable morphology. Here, non-degenerate pump-probe differential transmission studies with varying pump-fluence have been carried out on single-phase 2H–MoSe2 and mixed-phase 1T/2H–MoSe2 nanosheets to characterize their excited carrier dynamics. For both the samples, the differential probe transmission data show photo-induced bleaching at earlier pump-probe delay followed by photo-induced absorption unveiling signatures of exciton-state filling, exciton trapping, defect-mediated photo-induced probe absorption and recombination of defect bound excitons. The exciton trapping and photo-induced absorption by the trapped-carriers are estimated to occur with time constant of ∼430 to 500 fs based on multi-exponential modelling of the differential transmission till pump-probe delay of ∼3.5 ps. Biexponential modeling of the subsequent slow-recovery of the negative differential transmission at pump-probe delay ≳3.5 ps reveals that the exciton recombination happens via two distinct decay channels with ∼25 to 55 ps (τ1) and ≳1 ns (τ2) time constants. Pump-fluence dependent reduction in τ1 and further modelling of exciton population using higher order kinetic rate equation reveals that the two-body exciton-exciton annihilation governs the exciton recombination initially with a decay rate of ∼ 10 − 8 cm3s−1. The detailed analysis suggests that the fraction of total excitons that decay via long decay channel decreases with increasing exciton density for 2H–MoSe2, in contrast to 1T/2H–MoSe2 where the fraction of excitons decaying via long decay channel remains constant. [ABSTRACT FROM AUTHOR]

To enhance the gas sensing response performance of LDH materials, this study employed a hydrothermal synthesis method using sodium citrate as an inducer and urea as a precipitant. Graphene with excellent conductivity was used as a substrate. By controlling the solution's alkalinity, sheet-like NiFe-LDHs were successfully induced and assembled on the ultra-thin graphene surface. SEM and AFM characterizations confirmed that the flower-ball morphology of the LDHs, formed by the aggregation of nanosheets, created ultra-thin nanosheets of 6–8 nm that fully covered both sides of the 3–4 nm GO, rendering the material highly porous and well ordered (specific surface area of 111.39 m2 g−1). At ambient temperature (RH = 26%), the sample NF/rGO2 with 0.12 g of sodium citrate exhibited extremely high sensitivity and rapid response to 100 ppm NO2, with a response value and response/recovery time of 22.30 and 2.8/46 s, respectively. Moreover, the sensor demonstrated high selectivity and remarkable long-term stability for up to 100 days. The superior gas sensing performance can be attributed to the unique morphology of the composite material: the inhibited growth of LDHs on the graphene surface exposed numerous basic sites between layers, enhancing NO2 adsorption capability. Additionally, the staggered and orderly arrangement of ultra-thin LDHs significantly improved the electron transport rate. Therefore, the response/recovery time of the gas sensing material was considerably shortened, enhancing the gas sensing performance of the material. This study provides a novel approach for the preparation and synthesis of high-sensitivity and high-performance NO2 sensors at room temperature. [ABSTRACT FROM AUTHOR]

An ultrasensitive and selective voltammetric microsensor (multiwalled carbon nanotube [MWCNT]/carbon black nanoparticle [nCB])‐modified carbon paste microelectrode (mCPµE) with ultra‐trace level detection limit is designed for the determination of danofloxacin (DAN) in real samples. The (MWCNT/nCB)‐mCPµE consists of a carbon paste cavity microelectrode (MEC) modified with nCBs and MWCNTs. The nanostructure of the different MEC materials are characterized by scanning electron microscopy and electrochemical impedance spectroscopy. Under optimal conditions, a wide linear range (2.5 × 10−9–2.5 × 10−7 mol L−1) is obtained. The detection and quantification limits are estimated at 4.3 × 10−10 and 1.43 × 10−9 mol L−1, respectively. For the measurement of DAN in the presence of many possible interfering chemical molecules, the suggested microsensor demonstrates remarkable selectivity. Analysis of the real samples confirms that the (MWCNT/nCB)‐mCPµE is a suitable electrochemical sensor for the determination of DAN in wastewater and urine samples with satisfactory recoveries of 103.5%–104.6% and relative standard deviations less than 4.93%. Finally, in terms of sustainability (availability of materials used), analytical efficiency (precision and very low limit of quantification), and economic considerations (use of a very small quantity of materials), the proposed method outperforms previously reported methods. [ABSTRACT FROM AUTHOR]

We have developed a carbon dots/Ag (CDs/Ag) nanocomposite electrocatalyst for electrocatalytic nitrate reduction (NO3RR) to ammonia, achieving a remarkable NH3 faradaic efficiency (FE) of 98.48% and an ammonia yield rate of 198.12 μmol h−1 cm−2 at −0.93 V vs. RHE. Harnessing the CDs' ability to regulate the hydrogen evolution reaction (HER) and the presence of surface-active hydrogen (*H) on CDs/Ag effectively enhance the selectivity of silver nanomaterials toward ammonia synthesis. [ABSTRACT FROM AUTHOR]

The preparation of nanomaterials employing ionic liquids (ILs) and surface active ionic liquids (SAILs) in a relatively sustainable manner for different applications is reviewed. ILs offer structure directing and templating effects via inherent bi-continuous structures formed by the segregation of polar and non-polar domains. On the other hand, SAILs offer a structure-directing effect governed by their ability to lower the surface tension, self-assembling nature and interaction with precursors via ionic head groups. Binary mixtures of ILs with other relatively greener solvents or utilization of metal-based ILs (MILs), which act as precursors of metal ions, templates and stabilizing agents propose a new way to prepare a variety of nanomaterials. The introduction of SAILs that exfoliate 2D materials under low-energy bath sonication and also aid in photoreduction and stabilization of photocatalytically active nanomaterials at the surface of 2D materials poses a distinctive perspective in sustainable preparation and utilization of nanomaterials in different photocatalytic applications. The present feature article reviews the employment of distinctive properties of ILs in precise morphological control of nanomaterials, and their after-effects on their catalytic efficiencies. [ABSTRACT FROM AUTHOR]

With the growing adoption of hydrogen energy and the rapid advancement of Internet of Things (IoT) technologies, there is an increasing demand for high-performance hydrogen gas (H2) sensors. Among various sensor types, chemiresistive H2 sensors have emerged as particularly promising due to their excellent sensitivity, fast response times, cost-effectiveness, and portability. This review comprehensively examines the recent progress in chemiresistive H2 sensors, focusing on developments over the past five years in nanostructured materials such as metals, metal oxide semiconductors, and emerging alternatives. This review delves into the underlying sensing mechanisms, highlighting the enhancement strategies that have been employed to improve sensing performance. Finally, current challenges are identified, and future research directions are proposed to address the limitations of existing chemiresistive H2 sensor technologies. This work provides a critical synthesis of the most recent advancements, offering valuable insights into both current challenges and future directions. Its emphasis on innovative material designs and sensing strategies will significantly contribute to the ongoing development of next-generation H2 sensors, fostering safer and more efficient energy applications. [ABSTRACT FROM AUTHOR]

The purpose of the present study is to develop an easy and effective one-step pyrolytic method for synthesizing carbon dots (CDs) derived from folic acid (FA), denoted herein as FACDs. This method is green, inexpensive, and simplifies the synthesis of fluorescent carbon nanomaterials with enhanced and stable fluorescence. Moreover, the as-prepared FACDs are effective in the sensitive and selective detection of cysteine (Cys) by such a "turn-on" mechanism of fluorescence. FACDs have been able to realize a low detection limit of 1.7 × 10−7 M and a wide linear range from 5.0 × 10−7 to 8.0 × 10−5 M, successfully restoring quenched fluorescence in the presence of Cys. Obtained results confirm FACDs as a trustful high-performance sensor for various biological and environmental applications and pave the way for facile and efficient fluorescence-based detection platforms. [ABSTRACT FROM AUTHOR]

The electrochemical manipulation of organic compounds offers a promising alternative for the synthesis of valuable organic materials under mild conditions. In this study, the MoO2@NiO heterostructure was successfully synthesized as an efficient thin-film electrode material for electrochemical ethanol oxidation, using amorphous Ni(OH)x nanosheets as the precursor. During electrocatalytic ethanol oxidation, this electrode exhibited a significantly reduced overpotential, achieving a value of only 1.41 V at a current density of 50 mA cm−2. Additionally, product analysis revealed that the heterojunction electrode demonstrated high faradaic efficiency (70%) and selectivity (80%) for acetaldehyde. The outstanding performance of this electrode can be attributed to the in situ transformation of MoO2 species during the catalytic process. In the electrolyte, MoO2 exists as MoO42− and undergoes a series of processes including precipitation, dissolution, and redeposition on the electrode surface. These processes lead to the formation of a novel molecular outer layer, significantly enhancing the activity and stability of the electrode material. This study provides valuable insights into the potential replacement of anodes in the electrocatalytic oxidation of ethanol in aqueous solutions, thereby contributing to the development of more efficient and sustainable electrochemical systems. [ABSTRACT FROM AUTHOR]

MAX phase represents a new class of solids that combine some of the best attributes of metals and ceramics, exhibiting unusual, mechanical, electrical, and thermal properties. Further Ti 3 AlC 2 MAX phase is exfoliated to create 2D nanosheet material called Ti 3 C 2 MXene and both have unmatched qualities for difficult and unusual applications. The Ti 3 AlC 2 MAX phase powder is the precursor material to synthesize the Ti 3 C 2 MXene nanosheets, but the cost effective synthesis of Ti 3 AlC 2 powder is still a challenging problem which ultimately decides the quality and cost of Ti 3 C 2 MXene. In this paper, we present the novel synthesis of Ti 3 AlC 2 MAX phase using carbon flex generated as an industrial waste from aluminum, Steel, and other metal industries in composites production. To the best of our knowledge we first time novely report the use of Industrial waste carbon flex as a base carbon material to partially replace commercial graphitic carbon powder in Ti 3 C 2 synthesis. The effect of adding carbon flexes precursor to synthesizing Ti 3 AlC 2 MAX phase solving many current challenges. In present work we comparatively report the physicochemical study of the MAX phase synthesized with three different carbon precursors to establish the role of industrial waste carbon flex in the quantitative growth of Ti 3 C 2 MXene as the final product. [ABSTRACT FROM AUTHOR]

In this paper, pod-like Fe7Se8/C nanocomposite catalyst materials were prepared by MIL-88 selenide annealing and the as-prepared Fe7Se8/C nanocatalyst exhibited excellent electrocatalytic performance in neutral electrolyte for the electrocatalytic nitrogen reduction reaction (eNRR). The average ammonia yield rate was 7.11 μg h−1 mgcat−1 with a corresponding faradaic efficiency (FE) of 10.44% obtained at the optimum potential of −0.3 V. Moreover, the as-prepared Fe7Se8/C electrocatalyst shows good selectivity and stability for the eNRR. [ABSTRACT FROM AUTHOR]

A modified co-precipitation technique assisted with cetyltrimethylammonium bromide (CTAB) surfactant was used to synthesize a nanostructured and zinc-doped mixed metal oxide (Zn-Bi 2 O 3 /CeO 2) composite. Using X-ray diffraction (XRD), the synthesized nanocomposite was studied in terms of its crystal structure, grain size, percentage crystallinity, and percentage porosity. Energy dispersive X-ray elemental analysis (EDX) was used to ascertain the chemical composition, SEM to confirm the creation of nanostructure material, and Fourier transform infrared spectroscopy (FTIR) to extract the existing functional groups. Investigation of light harvesting properties (UV/Vis) and thermogravimetric analysis (TGA) reveals that the doped composite exhibits a band gap driven by visible light and remarkable thermal stability at high temperatures. The pH value at which a material's net charge is zero, known as pH pzc , is 7.93 for the doped mixed metal oxide composite. The Zn-Bi 2 O 3 /CeO 2 nanocomposite effectively eliminates 98.4 percent of the quinolone antibiotic (levofloxacin) via a mechanism that integrates sorption and photocatalytic degradation induced by visible light. To determine the optimal circumstances for the efficient operation of a photocatalyst, we experimented with different time intervals, beginning drug concentrations, catalyst dosages, operating temperatures, and pH levels. Reusability tests and post-activity FTIR analysis were used to investigate the long-term usability and structural stability of the newly developed doped composite photocatalyst. The scavenging tests revealed a potential photocatalytic mechanism to explain the annihilation of the levofloxacin drug on the synthesized catalyst. The physicochemical and photocatalytic evaluations recommend that the assembled integrated material has excellent potential for mineralizing medicinal products in pharmaceutical wastes. [Display omitted] [ABSTRACT FROM AUTHOR]

In our study, we focused on gas sensing, particularly ammonia detection. We synthesized and examined three types of nanoparticles: pure and conducting polymer-based TiO 2 nanoparticles. The nanoparticles were prepared by an easy sol-gel approach. All of the samples were characterized using XRD, FTIR, UV–vis, FESEM, EDAX and BET. Gas sensing measurements were carried out for each sample. Among them, PEG-TiO 2 stood out with remarkable gas sensing abilities, distinguishing it from other gas detection technologies. We thoroughly investigated the sensor performance, focusing close scrutiny to metrics such as response and recovery times. The greatest reduction in response time and recovery time (95 s/123 s) was achieved at 25 ppm. These metrics provide insights into how quickly the sensor detects and recovers from the presence of the target gas. Our findings offer important insights for optimizing the sensor performance of PEG-TiO 2 , highlighting its remarkable gas sensing capabilities. [ABSTRACT FROM AUTHOR]

For the purpose of achieving boron nitride nanosheets (BNNSs) intrinsic strengthening and relating microscopic interface characteristics to macroscopic mechanical behavior in BNNSSs/Ti composites, the BNNSs/Ti composites were fabricated by field-assisted hot pressing (FHP) and subsequent 923K, 1023K, 1123K or 1223K hot-rolling (HR). Herein, we succeeded in simultaneously maintaining the BNNSs intrinsic structure and considerable interfacial nano-sized TiB w. Interestingly, the superior tensile property (UTS: 1166 MPa, El. 9.3 %) was realized in 1123K as-rolled BNNSs/Ti composite, whereas the dramatic ductility deterioration exhibited in composite when the HR temperature setting at 1223K. BNNSs load transfer and interface failure behavior were investigated by direct in-situ tensile SEM observation. The nano-TiB w on partially reacted BNNSs played a predominant role on BNNSs load-transfer efficiency and contributed to the desirable ductility. These findings highlighted the untapped potential for improving mechanical properties in BNNSs reinforced metal matrix composite. [ABSTRACT FROM AUTHOR]

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An anatase/TiO2(B) homojunction loaded with Au nanoparticles was synthesized, achieving a C2H6 yield rate of 170 μmol g−1 h−1 in a flow photoreactor. The homojunction reduces TiO2(B)'s strong oxidative ability, offering a more moderate environment for methane dehydrogenation, while Au aids in charge mitigation and methyl radical coupling. The catalyst highlights homojunction engineering and a ternary synergistic effect in photocatalytic CH4 coupling. [ABSTRACT FROM AUTHOR]

Herein, stacked films of WO3 separated by indium nanosheets are fabricated as quad‐band antennas suitable for high‐frequency applications. The amorphous WO3 films and indium nanosheets are coated onto each other using the thermal evaporation technique under a high vacuum pressure of 10−5 mbar. The stacked layers of Pt/WO3/In/WO3/Pt are structurally and electrically characterized. The tunneling‐type quad‐band antennas are tested in the driving frequency domain of 0.01–1.80 GHz and a low signal amplitude of 0.10 V. It is observed that the insertion of indium nanosheets between layers of WO3 remarkably increases the width of the tunneling barrier from 55 to 70 nm without altering the tunneling barrier height. This also enhances the cutoff frequency at a quad‐band frequency of 1.80 GHz from 10 GHz to 1.46 THz and increases the return loss values from ≈5 to 21 dB. A widely tunable cutoff frequency extending from 0.30 GHz to 1.46 THz can be obtained based on the selected driving signal frequency. The microwave‐controlling features of the Pt/WO3/In/WO3/Pt devices, with their high cutoff frequency and high power transmission ratios at the quad‐band frequency, make them attractive for 6G technology. [ABSTRACT FROM AUTHOR]

Inorganic-organic composite proton exchange membranes (PEMs) are promising substitutes in proton exchange membrane fuel cells. To improve the compatibility between inorganic fillers and polyelectrolytes, along with alleviating filler aggregation, a series of composite PEMs incorporating both sulfonated titanium dioxide nanotubes (sTiNT) and graphitic carbon nitride nanosheets (g-C 3 N 4) into sulfonated poly (aryl ether sulfone) s (SPAES) have been prepared. The distinct morphology of sTiNT and g-C 3 N 4 , coupled with their respective sulfonic acids and amine/imine functionalities, endow the fillers with exceptional compatibility and dispersivity within SPAES. The obtained SPAES/sTiNT/g-C 3 N 4 membranes exhibit superior thermal, size and mechanical stability, robust oxidative resistance, together with high proton conductivity. The SPAES/sTiNT/g-C 3 N 4 (1/3) membrane particularly exhibits proton conductivity of 202 mS/cm and swelling below 10% (90 °C), a hydrogen fuel cell output of 512 mW/cm2 (80 °C), which is 1.6 times of the SPAES membrane. The results suggest the great potential of multi-filler compositing strategy for alternative PEMs exploration. [Display omitted] • Sulfoalkoxyl-functionalized titanium nanotubes (sTiNT) have been synthesized. • STiNT and g-C 3 N 4 nanosheets are co-doped into SPAES matrix to prepare PEMs. • 1D/2D fillers co-doped PEMs exhibit exceptional compatibility and dispersivity. • Enhanced dimensional stability and conductivity result from co-doping strategy. • SPAES/sTiNT/g-C 3 N 4 (1/3) has 1.2 times higher σ and 1.6 times better power output. [ABSTRACT FROM AUTHOR]

The interactions between ZnO nanorods and H2 at different temperatures are revealed with 17O solid-state NMR spectroscopy in combination with a variety of different characterization methods. These results should enable further understanding of the adsorption properties of H2 on ZnO nanocrystalline or related nanomaterials. [ABSTRACT FROM AUTHOR]

Pseudocapacitors are an emerging class of energy storage materials that offer an attractive compromise between the energy density of batteries and power density of electric double‐layer capacitors. Decreasing particle size and increasing surface area of battery materials is a common approach for introducing pseudocapacitive behavior and increasing power density. However, in many cases, as the crystal size is reduced, lattice disorder of unknown extent is also introduced, making it difficult to characterize the relative contribution of size and disorder to fast‐charging performance. In this work, a series of nanostructured MoS2 materials are synthesized with different crystallite sizes and degrees of crystallinity to decouple the effects of size and disorder on charge/discharge kinetics. The extent and type of disorder in each material is quantified by total X‐ray scattering experiments and pair distribution function analyses. Electrochemical characterization, including galvanostatic rate capability, cyclic voltammetry, and various kinetic analyses, are used to demonstrate that both decreasing particle size and introducing lattice disorder are effective strategies for increasing charge storage kinetics, and that the effects are additive. Finally, operando X‐ray diffraction measurements show that both size and disorder can be used suppress first‐order Li+ intercalation‐induced phase transitions, a key feature for enabling pseudocapacitive charge storage. [ABSTRACT FROM AUTHOR]

New generation of nanomaterials with organelle‐level precision provide significant promise for targeted attacks on mitochondria, exhibiting remarkable therapeutic potency. Here, we report a novel amphiphilic phenolic polymer (PF) for the mitochondria‐targeted photodynamic therapy (PDT), which can trigger excessive mitochondrial DNA (mtDNA) damage by the synergistic action of oxidative stress and furan‐mediated DNA cross‐linking. Moreover, the phenolic units on PF enable further self‐assembly with Mn2+ via metal‐phenolic coordination to form metal‐phenolic nanomaterial (PFM). We focus on the synergistic activation of the cGAS‐STING pathway by Mn2+ and tumor‐derived mtDNA in tumor‐associated macrophages (TAMs), and subsequently repolarizing M2‐like TAMs to M1 phenotype. We highlight that PFM facilitates the cGAS‐STING‐dependent immunity at the organelle level for potent antitumor efficacy. [ABSTRACT FROM AUTHOR]

Interest in antibacterial nanomaterials has surged in recent years, driven by the rise in antibiotic resistance among microbes. However, their practical application remains limited because many crucial properties have yet to be thoroughly investigated. In this study, we have developed novel nanofibrous membranes based on hydrophilic polyacrylonitrile (PAN) or hydrophobic polycaprolactone (PCL) with embedded hydrophilic or hydrophobic zinc(II)phthalocyanines (ZnPcs) as photosensitizers and investigated their water disinfection properties. Several key characteristics were evaluated to link the activity of the material and composition/structure. As demonstrated by reflectance UV/Vis spectroscopy, the aggregation states of dyes within the polymer support vary significantly. We have proposed and validated the use of fluorescence lifetime imaging (FLIM) for visualizing "active sites" in the membranes. The results of this study provide useful insights for the engineering of photoactive nanomaterials with tailor‐made properties and highlight the crucial role of the nature of polymeric support in modulating the material's activity. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate a straightforward and versatile approach for fabricating flexible SERS substrates for highly sensitive fentanyl detection. Our design strategy integrates the synthesis of a yolk–shell structured plasmonic nanomaterial with a flexible cellulose substrate. The resulting SERS platform demonstrates excellent sensing capabilities, achieving a fentanyl detection limit as low as 4.89 ng mL−1. [ABSTRACT FROM AUTHOR]

A template-directed synthesis of one-dimensional hexagonal PdTe nanowires using Te nanowires as a template through a two-step hydrothermal process is developed, which exhibit excellent mass activity of 4.4 A mgPd−1 for ethanol electrooxidation in an alkaline medium. This work enriches the controlled synthesis of one-dimensional noble metal chalcogenide nanomaterials. [ABSTRACT FROM AUTHOR]

Pb-based perovskites play pivotal roles in ferroelectric research. In the search for new Pb-based ferroelectrics, we investigated the ferroelectric properties of Dion–Jacobson type CsPb2Nb3O10 and exfoliated 2D nanosheets. Ferroelectricity in CsPb2Nb3O10 was demonstrated for the first time. CsPb2Nb3O10 adopted a polar tetragonal structure with a modest TC = 260 °C and polarization PS = 7.93 μC cm−2; the polarization mainly arose from the out-of-plane displacements of Nb5+ ions and nearby oxygens. CsPb2Nb3O10 layered perovskite offers additional advantages for tailoring ferroelectric nanomaterials, as exfoliated 2D nanosheets provide novel platforms for investigating ferroelectric properties down to the 2D limit. Piezoresponse force microscopy confirmed stable ferroelectricity even in exfoliated 2D Pb2Nb3O10 nanosheets. [ABSTRACT FROM AUTHOR]

When exposed to an alternating current (AC) electric field, a polarized microparticle is moved by the interaction between the voltage-induced dipoles and the AC electric field under dielectrophoresis (DEP). The DEP force is widely used for manipulation of microparticles in diverse practical applications such as 3D manipulation, sorting, transfer, and separation of various particles such as living cells. In this study, we propose the integration of surface-enhanced Raman spectroscopy (SERS), an extremely sensitive and versatile technique based on the Raman scattering of molecules supported by nanostructured materials, with DEP using a microfluidic device. The microfluidic device combines microelectrodes with gold nanohole arrays to characterize the electrophysiological and biochemical properties of biological cells. The movement of particles, which varies depending on the electrical properties such as conductivity and permittivity of particles, can be manipulated by the cross-frequency change. For proof of concept, Raman spectroscopy using the DEP–SERS integration was performed for polystyrene beads and biological cells and resulted in an improved signal-to-noise ratio by determining the direction of the DEP force applied to the cells with respect to the applied AC power and collecting them on the nanohole arrays. The result illustrates the potential of the concept for simultaneously examining the electrical and biochemical properties of diverse chemical and biological microparticles in the microfluidic environment. [ABSTRACT FROM AUTHOR]

• Nanostructured neural probes enable multimodal sensing and advanced imaging.. • Advanced probes integrate electrodes, sensors, and waveguides for precise analysis. • Decoding neural codes, brain mapping, and therapeutic advances hold great promise. • Addressing data integration and biocompatibility require multifaceted developments. Neuroprobes that use nanostructured photonic interfaces are capable of multimodal sensing, stimulation, and imaging with unprecedented spatio-temporal resolution. In addition to electrical recording, optogenetic modulation, high-resolution optical imaging, and molecular sensing, these advanced probes combine nanophotonic waveguides, optical transducers, nanostructured electrodes, and biochemical sensors. The potential of this technology lies in unraveling the mysteries of neural coding principles, mapping functional connectivity in complex brain circuits, and developing new therapeutic interventions for neurological disorders. Nevertheless, achieving the full potential of nanostructured photonic neural probes requires overcoming challenges such as ensuring long-term biocompatibility, integrating nanoscale components at high density, and developing robust data-analysis pipelines. In this review, we summarize and discuss the role of photonics in neural probes, trends in electrode diameter for neural interface technologies, nanophotonic technologies using nanostructured materials, advances in nanofabrication photonics interface engineering, and challenges and opportunities. Finally, interdisciplinary efforts are required to unlock the transformative potential of next-generation neuroscience therapies. [ABSTRACT FROM AUTHOR]

A method to obtain sodium titanate nanoribbons starting from a mixture of brookite and anatase TiO₂ nanopowder is described. As-prepared TiO 2 nanopowder with a major brookite phase was used as a precursor in an alkaline hydrothermal approach, where the temperature was kept at 200 °C. The influence of hydrothermal treatment and consequent annealing temperature (T = 500 °C) on the crystal structure, phase composition, and morphology of samples were investigated by X-ray powder diffraction (XRPD), Raman and FTIR spectroscopy, and electron microscopy techniques (FESEM, HRTEM). All these methods point out that the hydrothermally treated sample, containing the NaTi 3 O 6 (OH)(H 2 O) 2 , Na 2 Ti 3 O 7 , and Na 2 Ti 9 O 19 , is dominated by layer-structured sodium hydroxititanate dihydrate. The annealing leads to the formation of rare sodium titanates, Na 3 Ti 6 O 13 and Na 2 Ti 9 O 19 , with tunnel structures where the hexatitanate with increased sodium content prevails. The photocatalytic activity of synthesized nanostructures was tested in the degradation process of Reactive Orange (RO16) azo-dye upon UV excitation. It appears that photocatalytic activity is lower after hydrothermal treatment, but subsequent annealing makes sodium titanate nanoribbons faster in the degradation of RO16. The research implies that these sodium titanate nanostructures are promising photocatalytic materials and should be considered in the future for removing different pollutants from water. [ABSTRACT FROM AUTHOR]

Energy storage technologies play a crucial role in addressing the intermittent characteristics of renewable energy sources, improving the stability of electrical grids, and decreasing the release of greenhouse gas emissions. In this study, we presented nickel indium oxalate (Ni 1-x In x C 2 O 4) as a promising material with potential applications in the field of electrochemical energy storage. The as-prepared Ni-In- oxalate sample was subjected to different physical characterizations, including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Regarding the electrochemical energy storage capability, the Ni 1-x In x C 2 O 4 electrode material exhibited a specific capacitance of 835 F g−1 (417.5 C g−1) at 1 A g−1. The incorporation of nickel (Ni) into the indium (In) oxalate nanoplates enhances their electrochemical performance. The presence of Ni in the nanoplates generated from substrate, improving the overall conductivity of the material and enhances its electrochemical reactions, thus leading to improved energy storage capabilities. [ABSTRACT FROM AUTHOR]