Nanosheet Research Articles

Activity–Stability Trends of the Sb-SnO2@RuOx Heterostructure toward Acidic Water Oxidation

Accomplishments of enhanced activity and durability are a major concern in the design of catalysts for acidic water oxidation. To date, most studied supported metal catalysts undergo fast degradation in strongly acidic and oxidative environments due to improper controlling of the interface stability caused by their lattice mismatches. Here, we evaluate the activity-stability trends of in situ crystallized antimony-doped tin oxide (Sb-SnO2)@RuOx (Sb-SnO2@RuOx) heterostructure nanosheets (NSs) for acidic water oxidation. The catalyst prepared by atomic layer deposition of a conformal Ru film on antimony-doped tin sulfide (Sb-SnS2) NSs followed by heat treatment highlights comparable activity but longer stability than that of the ex situ catalyst (where Ru was deposited on Sb-SnO2 followed by heating). Air calcination for in situ crystallization allows the formation of hierarchical mesoporous Sb-SnO2 NSs from as-prepared Sb-SnS2 NSs and parallel in situ transformation from Ru to RuOx, resulting in a compact heterostructure. The significance of this approach significantly resists corrosive dissolution, which is justified by the enhanced oxygen evolution reaction (OER) stability of the catalyst compared to most of the state-of-the-art ruthenium-based catalysts including Carbon@RuOx (which shows ∼10 times higher dissolution) as well as Sb-SnO2@Com. RuOx and Com. RuO2. This study demonstrates the controlled interface stability of heterostructure catalysts toward enhancing OER activity and stability.

Photocatalytic and Glucose Sensing Properties of ZnO-Based Nanocoating

Here, we report a simple and versatile synthesis of low-dimensional ZnO nanosheet (NS) arrays modified with Fe2O3 (hematite) to assemble photocatalytic coatings and non-enzymatic glucose sensors. Photocatalytic coatings made of widespread elements (zinc and iron) were tested for methylene blue (MB) dye decolorization under ultraviolet and visible (UV-vis) irradiation. A comparative study of unmodified and modified ZnO NS photocatalysts revealed a significant decrease in the dye concentration in 180 min when ZnO/Fe2O3 arrays were used. Size dependence efficiency of the hematite layer deposited onto ZnO is presented. A study of the sensitivity of biosensors made of ZnO nanostructures and ZnO/Fe2O3 nanocomposites for glucose detection showed an improvement in sensitivity with increased Fe2O3 thickness. The structure and morphology of low-dimensional coatings were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDX). The optical properties of nanoarrays showed a red shift of absorption after modifying ZnO with hematite layers, which holds good promise for expanding photocatalytic activity in the visible region.

New Insights into the Surfactant-Assisted Liquid-Phase Exfoliation of Bi2S3 for Electrocatalytic Applications

During water electrolysis, adding an electrocatalyst for the hydrogen evolution reaction (HER) is necessary to reduce the activation barrier and thus enhance the reaction rate. Metal chalcogenide-based 2D nanomaterials have been studied as an alternative to noble metal electrocatalysts because of their interesting electrocatalytic properties and low costs of production. However, the difficulty in improving the catalytic efficiency and industrializing the synthetic methods have become a problem in the potential application of these species in electrocatalysis. Liquid-phase exfoliation (LPE) is a low-cost and scalable technique for lab- and industrial-scale synthesis of 2D-material colloidal inks. In this work, we present, to the best of our knowledge, for the first time a systematic study on the surfactant-assisted LPE of bulk Bi2S3 crystalline powder to produce nanosheets (NSs). Different dispersing agents and LPE conditions have been tested in order to obtain colloidal low-dimensional Bi2S3 NSs in H2O at optimized concentrations. Eventually, colloidally stable layered nano-sized Bi2S3 suspensions can be produced with yields of up to ~12.5%. The thus obtained low-dimensional Bi2S3 is proven to be more active for HER than the bulk starting material, showing an overpotential of only 235 mV and an optimized Tafel slope of 125 mV/dec. Our results provide a facile top-down method to produce nano-sized Bi2S3 through a green approach and demonstrate that this material can have a good potential as electrocatalyst for HER.

Ru(II) Complex Grafted Ti3C2Tx MXene Nano Sheet with Photothermal/Photodynamic Synergistic Antibacterial Activity

For a long time, the emergence of microbial drug resistance due to the abuse of antibiotics has greatly reduced the therapeutic effect of many existing antibiotics. This makes the development of new antimicrobial materials urgent. Light-assisted antimicrobial therapy is an alternative to antibiotic therapy due to its high antimicrobial efficiency and non-resistance. Here, we develop a nanocomposite material (Ru@MXene) which is based on Ru(bpy)(dcb)2+ connected to MXene nanosheets by ester bonding as a photothermal/photodynamic synergistic antibacterial material. The obtained Ru@MXene nanocomposites exhibit a strengthened antimicrobial capacity compared to Ru or MXene alone, which can be attributed to the higher reactive oxygen species (ROS) yield and the thermal effect. Once exposed to a xenon lamp, Ru@MXene promptly achieved almost 100% bactericidal activity against Escherichia coli (200 μg/mL) and Staphylococcus aureus (100 μg/mL). This is ascribed to its synergistic photothermal therapy (PTT) and photodynamic therapy (PDT) capabilities. Consequently, the innovative Ru@MXene can be a prospective non-drug antimicrobial therapy that avoids antibiotic resistance in practice. Notably, this high-efficiency PTT/PDT synergistic antimicrobial material by bonding Ru complexes to MXene is the first such reported model. However, the toxic effects of Ru@MXene materials need to be studied to evaluate them for further medical applications.

Polyvinyl alcohol/montmorillonite/magnesium diboride fibers with superior flame retardancy, strength, and flexibility

Using delaminated montmorillonite (MMT) nanosheets (NSs) and MgB2 NSs as crosslinking units and methanol as a coagulation bath, polyvinyl alcohol (PVA)/MMT/MgB2 composite fibers with excellent mechanical and flame-retardant properties were fabricated via wet spinning, and their flame retardancy was studied via limiting oxygen index (LOI) and microcaloric combustion calorimetry measurements. The delaminated MMT NSs (45 wt%) and MgB2 NSs (5 wt%) can be uniformly dispersed into PVA. The synergistic effect between the MgB2 NSs and the MMT NSs as well as the formation of a dense char layer with a continuous crosslinked network significantly enhance the mechanical properties and flame retardancy of the PVA/MMT/MgB2-5 composite fibers. The fibers possess not only a high mechanical strength of 304 MPa and an elongation at break of 9.8% but also an LOI value of 49.8% and a self-extinguishing time of only 1.2 s for a single fiber. Furthermore, the peak heat release rate and the total heat release are 89% and 85% lower than those of the pure PVA fibers, respectively. PVA/MMT/MgB2-5 composite fibers are promising candidates for application in the textile, architecture, and fire protection fields due to their outstanding flame retardancy, high mechanical strength, and good flexibility.

Fabrication of Highly Oriented Ultrathin Zirconium Metal‐Organic Framework Membrane from Nanosheets towards Unprecedented Gas Separation

AbstractConcurrent regulation of crystallographic orientation and thickness of zirconium metal–organic framework (Zr‐MOF) membranes is challenging but promising for their performance enhancement. In this study, we pioneered the fabrication of uniform triangular‐shaped, 40 nm thick UiO‐66 nanosheet (NS) seeds by employing an anisotropic etching strategy. Through innovating confined counter‐diffusion‐assisted epitaxial growth, highly (111)‐oriented 165 nm‐thick UiO‐66 membrane was prepared. The significant reduction in thickness and diffusion barrier in the framework endowed the membrane with unprecedented CO2 permeance (2070 GPU) as well as high CO2/N2 selectivity (35.4), which surpassed the performance limits of state‐of‐the‐art polycrystalline MOF membranes. In addition, highly (111)‐oriented 180 nm‐thick NH2‐UiO‐66 membrane showing superb H2/CO2 separation performance with H2 permeance of 1230 GPU and H2/CO2 selectivity of 41.3, was prepared with the above synthetic procedure.

Fabrication of Highly Oriented Ultrathin Zirconium Metal-Organic Framework Membrane from Nanosheets towards Unprecedented Gas Separation.

Concurrent regulation of crystallographic orientation and thickness of zirconium metal-organic framework (Zr-MOF) membranes is challenging but promising for their performance enhancement. In this study, we pioneered the fabrication of uniform triangular-shaped, 40 nm thick UiO-66 nanosheet (NS) seeds by employing an anisotropic etching strategy. Through innovating confined counter-diffusion-assisted epitaxial growth, highly (111)-oriented 165 nm-thick UiO-66 membrane was prepared. The significant reduction in thickness and diffusion barrier in the framework endowed the membrane with unprecedented CO2 permeance (2070 GPU) as well as high CO2 /N2 selectivity (35.4), which surpassed the performance limits of state-of-the-art polycrystalline MOF membranes. In addition, highly (111)-oriented 180 nm-thick NH2 -UiO-66 membrane showing superb H2 /CO2 separation performance with H2 permeance of 1230 GPU and H2 /CO2 selectivity of 41.3, was prepared with the above synthetic procedure.

Pyrene based two-dimensional metal-organic framework nanosheets for targeted chemo-chemodynamic therapy

Metal-organic frameworks (MOFs), as drug delivery carriers, have been extensively studied in biomedical fields. Among them, two-dimensional metal-organic frameworks (2D MOFs) have the advantages of high metal active sites, large specific surface area and easy surface modification. Herein, a novel 2D MOFs nanosheets were constructed by Cu2+ and 1,3,6,8-tetrakis(p-benzoic acid)pyrene (H4TBAPy) under hydrothermal conditions (Cu-MOFs). Then the DOX@Cu-MOFs-HA nanosheets (NSs) were gained through loading doxorubicin (DOX) and modifying with hyaluronic acid (HA), where Cu2+/Cu+ can initiate Fenton-like reaction for chemodynamic therapy (CDT) and HA can actively target tumor cells. In the tumor microenvironment, DOX@Cu-MOFs-HA NSs was gradually degraded to release DOX and Cu2+, where Cu2+ was reduced to Cu+ with glutathione (GSH) to catalyze the conversion of H2O2 to yield highly toxic ROS through a Fenton-like reaction, and DOX acted on the nucleus to induce apoptosis and successfully achieved the combination of chemo-chemodynamic therapy. This strategy provides a new perspective for two-dimensional MOFs NSs in the field of drug delivery.

Enhanced ammonia sensing response based on Pt-decorated Ti3C2T x /TiO2 composite at room temperature

Herein, we report a Pt-decorated Ti3C2T x /TiO2 gas sensor for the enhanced NH3 sensing response at room temperature. Firstly, the TiO2 nanosheets (NSs) are in situ grown onto the two-dimensional (2D) Ti3C2T x by hydrothermal treatment. Similar to Ti3C2T x sensor, the Ti3C2T x /TiO2 sensor has a positive resistance variation upon exposure to NH3, but with slight enhancement in response. However, after the loading of Pt nanoparticles (NPs), the Pt-Ti3C2T x /TiO2 sensor shows a negative response with significantly improved NH3 sensing performance. The shift in response direction indicates that the dominant sensing mechanism has changed under the sensitization effect of Pt NPs. At room temperature, the response of Pt-Ti3C2T x /TiO2 gas sensor to 100 ppm NH3 is about 45.5%, which is 13.8- and 10.8- times higher than those of Ti3C2T x and Ti3C2T x /TiO2 gas sensors, respectively. The experimental detection limit of the Pt-Ti3C2T x /TiO2 gas sensor to detect NH3 is 10 ppm, and the corresponding response is 10.0%. In addition, the Pt-Ti3C2T x /TiO2 gas sensor shows the fast response/recovery speed (23/34 s to 100 ppm NH3), high selectivity and good stability. Considering both the response value and the response direction, the corresponding gas-sensing mechanism is also deeply discussed. This work is expected to shed a new light on the development of noble metals decorated MXene-metal oxide gas sensors.

CFET SRAM DTCO, Interconnect Guideline, and Benchmark for CMOS Scaling

This article explores and evaluates six-transistor static random access memory (SRAM) bitcell design options for sequential and monolithic complementary field-effect transistors (CFET) in 5-Å-compatible (A5) and 3-Å-compatible (A3) technology. A5 CFET offers up to 55% and 40% SRAM bitcell area scaling due to stacked architecture as compared to 14-Å-compatible (A14) nanosheet (NS) technology and 10-Å-compatible (A10) forksheet (FS) technology counterparts, respectively. A dielectric isolation wall (DIW) between gates is introduced in A3 CFET SRAM as a scaling booster. Replacement of gate-cuts with DIW results in up to 17% bitcell area scaling in A3 as compared to A5 CFET SRAM. However, aggressive area scaling introduces routing complexity and limits the node-to-node power and performance (PP) gain. Thus, the interconnect design guidelines are provided to overcome these challenges for power, performance, and area (PPA) enhancements of high-density (HD) SRAM.

Synergistic effect of polypyrrole modified WS2 nanosheets on visible light assisted catalysis for the removal of chromium (VI) and humic acid

In this work, a novel nanocomposite was synthesized by the surface modification of tungsten disulphide (WS2) with polypyrrole (PPy) for the photocatalytic removal of heavy metal ions (chromium hexavalent (Cr (VI)) and natural organic contaminant (humic acid (HA)). The morphological analysis of synthesized samples was carried out using Field Emission Scanning Electron Microscopy (FESEM) which shows that PPy nanoparticles (NPs) are randomly distributed on the surface of WS2 nanosheets (NSs). The interlayer spacing of fringe width of WS2 NSs calculated from High Resolution Transmission Electron Microscopy (HRTEM) studies comes out to be 0.65 nm also in coherence with XRD analysis. Elemental analysis of synthesized nanocomposite was confirmed by using X-Ray Photoelectron Spectroscopy (XPS). The synthesized WP nanocomposite shown enhanced efficiencies (ɳCr ∼98.75% and ɳHA ∼77.78%) as compared to negligible efficiency of pristine WS2 (∼15% and 16%) and PPy (∼49% and 40%) for the reduction of Cr (VI) and degradation of HA, respectively. The enhanced removal efficiency of nanocomposite was attributed to decrease in the bandgap (2.03 to 1.80 eV), enhanced carrier concentrations (4.0 × 1030 cm−3 to 3.2 × 1031 cm−3) and low recombination rate (1.85 to 7.40 ns) of WP nanocomposite on the incorporation of PPy in WS2 as evident from UV–Vis, Mott-Schottky technique (MSK) and Time-correlated single-photon counting (TCSPC) decay measurement, respectively. The enhancement in removal efficiency is also attributed to the high surface area (160.36 m2/g) of the nanocomposite as analyzed using Brunauer-Emmett-Teller (BET) technique. The photocatalytic reduction efficiency was also studied as a function of pH (4,7 and 9). The reduction pathways follow second-order rate kinetics with high value of correlation coefficient (R2 ∼ 0.99). The proposed photocatalytic reduction mechanism was supported by a trapping study which shows that the superoxide radicals (⋅O2−) were the primary species taking part in photocatalytic reaction. Reusability test and stability of materials demonstrates promising photocatalytic performance of the synthesized nanocomposite.

Determining the Zero-Temperature-Coefficient Point From Device Simulation to Circuit for Improving Temperature Variation Immunity

Thermal issue emerges as one of the critical reliability concerns in integrated circuit design, especially for advanced technology. To improve the temperature immunity and reduce the thermal-related timing guard bands in digital circuits, in this work, we offer a new insight into the zero-temperature-coefficient (ZTC) based design strategy featuring minimizing the temperature-induced delay variation. An effective current-based method to facilitate the ZTC point ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {ZTC}}$ </tex-math></inline-formula> ) determination for standard cells is developed, which is demonstrated on advanced gate-all-around (GAA) nanosheet (NS) FETs from 300 to 425 K using the calibrated TCAD simulation. The <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {ZTC}}$ </tex-math></inline-formula> dependencies on the signal input slew rate, output capacitance, and self-heating effects (SHEs) are further investigated from the perspective of the effective current by tracing the voltage trajectory. The mixed-mode TCAD simulation results show that the frequency variation of ring oscillator (RO) reduces nearly ten times when operating near <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {ZTC}}$ </tex-math></inline-formula> and great power-performance trade-offs can also be achieved. The <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {ZTC}}$ </tex-math></inline-formula> determination for standard cells combined with the compensation effect among different standard cells benefits selecting the optimal zero-temperature-delay (ZTD) point in the target path, thereby helping to implement a robust digital design against temperature variation.

A Simulation Study of SiGe Shell Channel CFET for Sub-2-nm Technology Nodes

In this article, a SiGe shell complementary FET (CFET) composed of an inversion mode (IM) nFET and a junctionless accumulation mode pFET under 2-nm (N2) and 1.5-nm (N1.5) technology nodes was studied for the characteristics of a single device and the CMOS logic circuit using 3-D numerical simulation. A comparison study between Si shell nanosheet and SiGe shell CFET with a Ge mole fraction in the range of 0.5–0.9. Compared with the Si shell nanosheet (NS), the SiGe shell CFET improves the ON-state current, transconductance, transition frequency, and intrinsic delay up to 29%, 32%, 31%, and 21%, respectively. Due to the mobility improvement in SiGe shell CFET, the fall time, rise time, propagation delay, and maximum operating frequency of the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text {Si}_{{0.5}}\text {Ge}_{{0.5}}$ </tex-math></inline-formula> shell CFET are also improved up to 2%, 43%, 3%, and 3%, respectively, compared with their Si shell counterparts. This SiGe shell CFET has a lower parasitic RC, a smaller layout area, and better analog and digital performance at the sub-2-nm technology node. This makes it a promising architecture for future high-performance CMOS logic applications.

Structure and stability of Au, Au2 and Au8 cluster on Ni(111) supported h-BN sheet: Role of size and support towards oxygen bond activation

Atomic level heterogenous catalysis has been of importance for in-depth understanding and designing of novel catalytic material. Present work aims to investigate the chemical reactivity of Au, Au 2 and Au 8 cluster on hexagonal boron nitride nano sheet (h-BN) and its Ni(111) activated analogue using density functional theory (DFT). The average vertical separation of gold atom(s) from h-BN is significantly influenced by Ni(111) support. Oxygen molecule, which is the key reactant for any oxidation reaction, is considered as probe molecule to verify the reactivity. Contrary to the case of Au atom, which is the most reactive on free-standing h-BN, Au 2 and Au 8 clusters show higher reactivity on Ni supported h-BN. Thus the agglomeration of Au (Au–Au interaction) and Ni(111) support is important in controlling the reactivity and therefore, will play a key role to design Au based efficient catalyst for future. • On free-standing h-BNNS, Au atom and Au dimer favours on top B and N atoms, respectively. • With Ni (111) supported h-BNNS both Au and Au 2 favour on-top B atom. • On free-standing h-BNNS, Au elongates the O–O bond more than Au 2 and Au 8 . • On Ni (111) supported h-BNNS, the O–O bond elongation is maximum on Au 8 cluster. • The presence of Ni(111) support improves the catalytic activity by spin modulation of the B atoms of h-BNNS.

Atomically Precise Ni Nanoclusters for Improving Hydrogen Evolution Reaction Performance

The generation of green hydrogen via electrocatalytic water splitting is an emerging strategy in the prospect of developing future energy devices. Herein, we designed water-soluble atomically precise Ni nanoclusters (NCs) on MoSe2 nanosheets (NSs) to enhance the hydrogen evolution reaction (HER) performance. The strong UV–vis absorption band and matrix-assisted laser deposition ionization (MALDI) time-of-flight mass spectra confirm the formation of Ni7 NCs. The energy-dispersive X-ray spectroscopy mapping confirms the homogeneous distribution of Ni, Mo, and Se throughout the surface of the ultrathin NS. X-ray photoelectron spectroscopy study reveals the strong interfacial interaction between Ni NCs and MoSe2 in the nanocomposite by substantial electron density transferring from Ni NCs to the MoSe2 NSs. It is seen that the 5 wt % Ni/MoSe2 composite structure exhibits the most notable HER efficiency with an overpotential of 170 mV vs reversible hydrogen electrode @ 10 mA/cm2 which is significantly lower than that of bare MoSe2 NSs (350 mV). The significantly lower Tafel slope of the Ni/MoSe2 nanocomposite indicates that the HER kinetics of MoSe2 is accelerated in the presence of Ni NCs. The charge-transfer resistance of the nanocomposite is significantly low compared to pristine MoSe2, confirming the enhanced interfacial charge transfer. This work opens up further opportunities to design efficient and low-cost electrocatalysts for improving the HER performance by incorporating the advantages of both non-precious atomically precise metal NCs and transition-metal dichalcogenides in one system.

A Novel Source/Drain Extension Scheme with Laser-Spike Annealing for Nanosheet Field-Effect Transistors in 3D ICs.

This study proposed a novel source/drain (S/D) extension scheme to increase the stress in nanosheet (NS) field-effect transistors (NSFETs) and investigated the scheme by using technology-computer-aided-design simulations. In three-dimensional integrated circuits, transistors in the bottom tier were exposed to subsequent processes; therefore, selective annealing, such as laser-spike annealing (LSA), should be applied. However, the application of the LSA process to NSFETs significantly decreased the on-state current (Ion) owing to diffusionless S/D dopants. Furthermore, the barrier height below the inner spacer was not lowered even under on-state bias conditions because ultra-shallow junctions between the NS and S/D were formed far from the gate metal. However, the proposed S/D extension scheme overcame these Ion reduction issues by adding an NS-channel-etching process before S/D formation. A larger S/D volume induced a larger stress in the NS channels; thus, the stress was boosted by over 25%. Additionally, an increase in carrier concentrations in the NS channels improved Ion. Therefore, Ion increased by approximately 21.7% (37.4%) in NFETs (PFETs) compared with NSFETs without the proposed scheme. Additionally, the RC delay was improved by 2.03% (9.27%) in NFETs (PFETs) compared with NSFETs using rapid thermal annealing. Therefore, the S/D extension scheme overcame the Ion reduction issues encountered in LSA and significantly enhanced the AC/DC performance.

Boron doped 1T phase MoS2 as a cocatalyst for promoting photocatalytic H2 evolution of g-C3N4 nanosheets

As one of the 2D transition metal sulfides, 1T phase MoS2 nanosheets (NSs) have been studied because of their distinguished conductivity and suitable electronic structure. Nevertheless, the active sites are limited to a small number of edge sites only, while the basal plane is catalytically inert. Herein, we report that boron (B) doped 1T phase MoS2 NSs can replace precious metals as a co-catalyst to assist in photocatalytic H2 production of 2D layered g-C3N4 nanosheets (g-C3N4 NSs). The H2 evolution rate of prepared B-MoS2@g-C3N4 composites with 15 wt% B-MoS2 (B-MoS2@g-C3N4–15, 1612.75 µmol h−1 g−1) is 52.33 times of pure g-C3N4 NSs (30.82 µmol h−1 g−1). Furthermore, the apparent quantum efficiency (AQE) of B-MoS2@g-C3N4–15 composites under the light at λ = 370 nm is calculated and reaches 5.54%. The excellent photocatalytic performance of B-MoS2@g-C3N4–15 composites is attributed to the B ions doping inducing the distortion of 1T phase MoS2 crystal, which can activate more base planes to offer more active sites for H2 evolution reaction (HER). This work of B-MoS2@g-C3N4 composites offers experience in the progress of effective and low-price photocatalysts for HER.

Injectable FHE+BP composites hydrogel with enhanced regenerative capacity of tendon-bone interface for anterior cruciate ligament reconstruction.

Features of black phosphorous (BP) nano sheets such as enhancing mineralization and reducing cytotoxicity in bone regeneration field have been reported. Thermo-responsive FHE hydrogel (mainly composed of oxidized hyaluronic acid (OHA), poly-ε-L-lysine (ε-EPL) and F127) also showed a desired outcome in skin regeneration due to its stability and antibacterial benefits. This study investigated the application of BP-FHE hydrogel in anterior cruciate ligament reconstruction (ACLR) both in in vitro and in vivo, and addressed its effects on tendon and bone healing. This BP-FHE hydrogel is expected to bring the benefits of both components (thermo-sensitivity, induced osteogenesis and easy delivery) to optimize the clinical application of ACLR and enhance the recovery. Our in vitro results confirmed the potential role of BP-FHE via significantly increased rBMSC attachment, proliferation and osteogenic differentiation with ARS and PCR analysis. Moreover, In vivo results indicated that BP-FHE hydrogels can successfully optimize the recovery of ACLR through enhancing osteogenesis and improving the integration of tendon and bone interface. Further results of Biomechanical testing and Micro-CT analysis [bone tunnel area (mm2) and bone volume/total volume (%)] demonstrated that BP can indeed accelerate bone ingrowth. Additionally, histological staining (H&E, Masson and Safranin O/fast green) and immunohistochemical analysis (COL I, COL III and BMP-2) strongly supported the ability of BP to promote tendon-bone healing after ACLR in murine animal models.

FeS2 nanosheets-H2 O2 -NaHCO3 chemiluminescence method for procaine hydrochloride determination.

FeS2 nanosheets (NSs) were produced and exploited as a new catalyst for a chemiluminescence (CL) reaction. The characterization of FeS2 NSs was performed using spectroscopic methods. In this regard, transmission electron microscopy images showed that FeS2 NSs have a length of ~0.5-1μm. The direct optical band gap energy of FeS2 NSs was found to be 3.45 eV. Prepared FeS2 NSs were used to catalyze the NaHCO3 -H2 O2 CL reaction. It was found that procaine hydrochloride (PCH) could reduce the intensity of the FeS2 NSs-NaHCO3 -H2 O2 CL reaction so, with increasing PCH concentrations, the intensity of light emission decreased. Therefore, a simple and sensitive method was introduced to measure PCH with a linear range expanded from 1.00 × 10-6 to 1.00 × 10-3 mol L-1 and an 8.32 × 10-7 mol L-1 limit of detection. Studies related to the effect of foreign species and reaction mechanisms were performed. The application of the approach was verified by quantifying the PCH in the injection.

Coupled Femtosecond Laser Assisted Doping and Fragmentation of MoO3 Nanosheets Generates Plasmonic QDs with Strong NLO Response

AbstractThe ability to modulate the nonlinear optical (NLO) response of low‐dimensional metal oxides is highly desirable for diverse applications. It is shown here that the irradiation of a dispersion of 2D oxide (MoO3) nanosheets (NSs) by femtosecond laser pulses enables simultaneous scissoring of the NSs to form well‐dispersed MoO3 quantum dots (QDs) and the modulation of the NLO response in the visible and near‐infrared (NIR) regions. The inversion of the absorptive nonlinearity is observed combined with a larger enhancement of NLO response in the laser‐irradiated MoO3−x NSs and the as‐generated QDs, which is associated with the steady laser‐deprival of oxygen atoms and the resultant localized surface plasmon resonance due to electron doping. By leveraging the sub‐picosecond NLO response of the plasmonic MoO3−x QDs, the development of ultrafast optical switches is demonstrated for ultrashort pulse laser generation based on fiber lasers operating in the NIR regions. Furthermore, the strong field enhancement of these non‐noble metal plasmonic QDs is exploited for the fabrication of substrates for surface‐enhanced Raman scattering, which demonstrate a detection limit down to the part‐per‐billion level. This work delineates an efficient strategy for creating plasmonic oxide QDs with strong NLO response that is attractive for photonic applications.