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Optical tunneling is an effect extremely sensitive to wavelength changes. In this article, we use this effect to design a new type of biosensor. The tunneling effect is excited by long range surface plasmon resonance, the energy is concentrated in the sensing medium in the form of standing waves, which lead a very high wavelength sensitivity and quality factor. By using COMSOL for finite element analysis, for the sensor structure of BK7/Cytop /Al2O3/Ag/Al2O3/sensing media/air, a quality factor of 10296 RIU-1 is achieved under angle modulation, a sensitivity of 170,000 nm/ RIU and a quality factor of 11333 RIU-1 are obtained under wavelength modulation. At the same time, the advantage of this structure is that there is no excessive requirement on the refractive index of the material, and a good sensing effect can be achieved even if the material is cheap and easy to prepare. After optimization, this structure is suitable for sensing media with a refractive index of 1.335-1.375, which can be applied to most liquid solutions.

Bacteria is one of the main culprits that cause human diseases and pose long-term challenges to people’s health. Rare earth elements have unique antibacterial advantages, but little research is available. In this paper, we reported an antibacterial composite film based on lanthanum-doped carbon quantum dot nanoparticles (La@N-P-CQDs) and polyvinyl alcohol (PVA) film for fluorescence of antibiotics and accelerating wound healing. PVA/La@N-P-CQDs composite film presented excellent hydrophilicity, biocompatibility, fluorescence intensity, and antibacterial effects. The antibacterial activity of La@N-P-CQDs was evaluated by employing antibacterial assay using Escherichia coli (E.coli)and Staphylococcus aureus (S.aureus) in vitro. La@N-P-CQDs showed enhanced antibacterial activity compared with N-P-CQDs. Moreover, the PVA/La@N-P-CQDs composite film with 0.5 mg/mL La@N-P-CQDs showed better antibacterial capability and wound healing performance than PVA and PVA/N-P-CQDs films in bacterial adhesion experiment. PVA/La@N-P-CQDs composite film could be used for wound dressing in vivo experiment and had no side effects on major organs in mice. The antibacterial composite film significantly promoted in vivo wound healing process because of its multifunctional properties. Therefore, it was an excellent candidate for wound dressing.

Based on the excellent performances of nanocrystalline cellulose, sodium alginate, or K-carrageenan in Pb2+ adsorption, nanocrystalline cellulose/sodium alginate/K-carrageenan composite hydrogel beads were prepared to adsorb Pb(II) from aqueous solutions. The objective of this study was to demonstrate the excellent potential of the composite hydrogel beads for heavy metal ion adsorption. We successfully prepared ecofriendly Fe-modified nanocrystalline cellulose/sodium alginate/K-carrageenan composite hydrogel beads and characterized them. The structure and adsorption mechanism were investigated using scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy, and the optimal adsorption conditions were determined. The tricomponent hydrogel beads were robust and exhibited improved adsorption capacity for Pb2+ and good reusability. The adsorption results could be fitted well with a pseudo-second-order kinetic model and the Langmuir adsorption model. The maximum adsorption capacity obtained by fitting was 351.04 mg g−1. Recycling experiments revealed that the adsorption capacity of the adsorbent remained high after five cycles of reuse.

Although traditional commercially available porous carbon-fluorocarbon working pairs have shown promising applicability for adsorption cooling, advancements in engineered carbons may further improve the performance. Moreover, insights into structure-property relationships that target higher sorption capacities within these synthesized carbons may guide such materials' future design. We utilized hierarchically porous carbons (HPCs), synthesized with colossal microporous and mesoporous content characterized by high surface areas (up to 2689 m2/g) and pore volume values (up to 10.31 cm3/g) toward fluorocarbon R134a adsorption. This unique pore topology leads to exceptional R134a uptake, ∼250 wt %, outperforming the highest uptake carbon material to date, Maxsorb III (∼220 wt %). Material characterizations reveal that the outstanding R134a capacity may be attributed to textural properties and oxygen-terminated functional groups more than graphitization of the material. Most importantly, HPCs are efficiently utilized in a two-bed model chiller device, where the performance shows excellent working capacity (105 wt %, ∼2 times the value of reported carbon materials/R134a). Fluorocarbon adsorption on HPCs also displays fast kinetics (equilibrium time: ∼2 min) mainly driven by physical adsorption (Qst: ∼27 kJ/mol), characteristic of swiftly reversible behavior adsorption-desorption behaviors. This work provides a fundamental understanding of the applicability of HPCs/R134a working pair for adsorption cooling.

Chronic wound healing, impeded by bacterial infections and drug resistance, poses a threat to global human health. Antibacterial phototherapy is an effective way to fight microbial infection without causing drug resistance. Covalent organic frameworks (COFs) are a class of highly crystalline functional porous carbon-based materials composed of light atoms (e.g., carbon, nitrogen, oxygen, and borane), showing potential applications in the biomedical field. Herein, we constructed porphyrin-based COF nanosheets (TP-Por CON) for synergizing photodynamic and photothermal therapy under red light irradiation (e.g., 635 nm). Moreover, a nitric oxide (NO) donor molecule, BNN6, was encapsulated into the pore volume of the crystalline porous framework structure to moderately release NO triggered by red light irradiation for realizing gaseous therapy. Therefore, we successfully synthesized a novel TP-Por CON@BNN6-integrated heterojunction for thoroughly killing Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureusin vitro. Our research identified that TP-Por CON@BNN6 has favorable biocompatibility and biodegradability, low phototoxicity, anti-inflammatory properties, and excellent mice wound healing ability in vivo. This study indicates that the TP-Por CON@BNN6-integrated heterojunction with multifunctional properties provides a potential strategy for COF-based gaseous therapy and microorganism-infected chronic wound healing.

Surface modification of cellulose nanocrystals (CNC) is essential for improving their reactivity and adsorption capacity. Oxidation, as a conventional modification method of CNC, has strong reaction conditions, which may partially destroy the structure of CNCs. Herein, we propose a mild cellulose modification method, in which diethylenetriaminepentaacetic acid (DPTA) was grafted onto CNC with an aminosilane coupling agent. To facilitate the enrichment and recovery of adsorbents, we prepared magnetic CNC before grafting DPTA, and finally obtained magnetic carboxylic functionalized CNC (MCNC-DPTA). The effects of the reaction parameters on the adsorption process were systematically studied by transmission electron microscopy, X-ray diffraction, Vibration sample magnetometry, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Additionally, the effects of the solution pH, the initial concentration of Pb, and the adsorption time on the adsorption properties of the materials were evaluated. Furthermore, the structure, morphology, and thermal properties of the solution were systematically studied. After 6 cycle tests, the adsorption amount of Pb(II) by MCNC-DPTA was only reduced by 7%. These results show that MCNC-DPTA is an environment-friendly adsorption material with an excellent Pb(II) removal effect.

Antifouling ability and blood compatibility are critically important in the development of medical metallic implants for clinical applications. Here, we report the zwitterionic-phosphonate block polymer as a new type of high-efficiency antifouling coating for metallic substrates. Six block polymers (pSBMA-b-pDEMMP) with different segment lengths (nSBMA: nDEMMP = 10:25, 40:25, 100:25, 75:5, 75:40, 75:100) were prepared and anchored on titanium alloy (TC4) substrates. 1H nuclear magnetic resonance (NMR) results clearly showed the precise preparation of the block polymers. XPS analysis and water contact angle measurement indicated the successful construction of the block polymer on TC4 substrates. The relationship between the antifouling performance of the polymer coating and the length of pDEMMP and pSBMA segments in the block polymer was established. Results showed that the polymer containing the pSBMA segment above 40 repeat units could significantly inhibit protein adsorption, platelet adhesion, bacterial adhesion and cell adhesion, while the pDEMMP segment above 5 repeat units is able to generate stable zwitterionic polymer coating on TC4 substrates. This ease of production and high-efficiency antifouling modification strategy elucidated here may find broad application for biomedical implants and devices in clinical applications.

Excellent performances promoted by lattice oxygen have attracted wide attention for catalytic degradation of volatile organic compounds (VOCs). However, how to control the continuous regeneration of lattice oxygen from the support is seldom reported. In this study, we selected sepiolite supported manganese-cobalt oxides (CoxMn100-xOy) as model catalysts by tuning Co/(Co + Mn) mass ratio (x = 3%, 10%, 15%, and 20%) to enhance toluene degradation efficiency, owing to lattice oxygen regeneration by redox cycle existing at the interface and Mn species with high valence state, initiated by cobalt catalytic performance under the role of crystal field stability phase. The results of activity test show that the sepiolite-Co15Mn85Oy catalyst exhibit outperformances at 193 °C with 10,000 h−1 GHSV. In addition, the catalyst existed at the bottom of the “volcano” curve correlated T50 or T90 with Co/(Co + Mn) weight ratio is sepiolite-Co15Mn85Oy, conforming its outperformance. Further characterized by investigating active sites structural and electronic properties, the essential of superior catalytic activity is attributed to the grands of lattice oxygen continuous formation resulted from redox engineering based on the high atomic ratio of surface lattice oxygen with continuous refilled from the support and that of Mn4+/Mn3+ cycle initiated by cobalt catalytic behaviors. All in all, redox engineering, not only promotes grands of active species reversible regeneration, but supplies an alternative catalyst design strategy towards the terrific efficiency-to-cost ratio performance.

Smartphones today have attracted a continuous trend of pursuing narrow-bezel and full-screen displays. To allow for a more user-friendly front side fingerprint recognition in full-screen displays, it is crucial to develop an under-display type of fingerprint sensor. Among fingerprint sensing techniques, ultrasonic fingerprint sensing has been proved to be able to provide more distinctive features and give a high resistance to spoof attacks. However, until now no study about under-display ultrasonic fingerprint sensing has been reported. In this article, for the first time, multilayer under-display ultrasonic fingerprint sensor structure using various active materials/structures were theoretically designed and compared. Based on the theoretical analysis results, a lead zirconate titanate (PZT)-5A-based multilayer under-display ultrasonic fingerprint sensor with a resonant frequency of 20 MHz, and a −6-dB fractional bandwidth of more than 70% was fabricated to meet the requirements of resolution and sensitivity for the under-display ultrasonic fingerprint imaging applications. The prototyped sensor was characterized, and the fingerprint recognition capability was tested using a custom-made fingerprint-mimicking phantom. The phantom images were acquired based on the pulse-echo imaging method. With the 1 μJ impulse driving signal, the sensor was manipulated to image a 2.0 mm × 1.0 mm section of fingerprint-mimicking phantom by mechanical scanning, obtaining an electronic image with 500 × 500 DPI. The fingerprint-mimicking phantom imaging results suggest that the 20 MHz broadband PZT-based multilayer structure holds great potential for under-display ultrasonic fingerprint sensor applications.

Urgent requests for environmentally friendly clean energy and the development of modern electronic products have resulted in fervent research on novel energy storage technologies, particularly for supercapacitors. But supercapacitors suffer from low energy densities, restricting their development. In order to obtain high performance supercapacitors with a high energy density and power density, the indispensable factor is designing electrode materials with excellent capacitive performance. We have successfully prepared innovative materials and unique structures to apply in high-performance supercapacitors. The nanowire is good for making close contact with the electrolyte for fast ion diffusion, and the nanoflower sheet enables shortening the electron convey route and provides a number of reaction active sites. Herein, we use copper foam (CF) as the substrate, and binder-free core–shell nanoflower-like CuO/CF@NiCoMn–OH is designed as a battery-style positive electrode. Benefiting from the advantages of a metal–organic framework (MOF)-assisted growth strategy and simple hydrothermal dynamics, the prepared optimizing electrode structure delivers a distinguished specific capacity of 26.8 F cm–² at 8 mA cm–² (3356 F g–¹ at 1 A g–¹). The assembled CuO/CF@NiCoMn–OH//AC exhibits a high energy density of 37.28 W h kg–¹ and a power density of 170 W kg–¹, under a potential window of 1.5 V. This work implies that MOF-assisted construction of core–shell nanoflower-like CuO/CF@NiCoMn–OH has broad application prospects in high-performance energy storage equipment.

Microorganism invasion is still a severe threat for wound healing, which usually induces severe complications and cannot be eradicated completely. Thus, a biodegradable nanomaterial for guarding against bacteria-associated wound infection and accelerating wound healing is of vital importance. Here, black phosphorus nanosheets (BPs) were successfully decorated with cationic carbon dots (CDs) through an in situ growth strategy. The BPs@CDs exhibit photon-responsiveness and contact-responsiveness as an antibacterial agent, which shorten wound healing time. Moreover, the BPs@CDs show available photothermal and photodynamic therapy via exploring their photothermal properties and the ability of singlet-oxygen (1O2) production. Astonishingly, the BPs@CDs could possess antibacterial activity even without laser illumination due to an electrostatic attraction between bacteria and cationic CDs on the surface of BPs. This chemical therapy causes the antibacterial process to occur more accurately and for a faster 1O2 release to kill bacteria than in a normal process. Importantly, BPs@CDs display outstanding cytocompatibility and hemocompatibility. In vitro and in vivo investigations demonstrate that the BPs@CDs have enhanced antibacterial effect and can significantly accelerate skin tissue regeneration and wound closure. Given their antibacterial triple-combination therapy and excellent physicochemical properties, the broad application of BPs@CDs in bacteria-associated wound management is anticipated.

Room-temperature phosphorescent (RTP) carbon dots offer unique opportunities in information security applications, but the delay time of such materials reported thus far is typically shorter than 10 s and thus affects readout of the encoded information. Herein, a fast processable and one-step synthetic approach is developed for the preparation of N and P codoped carbonized polymer dots (NP-CPDs) exhibiting ultralong-lived RTP (URTP) responses. The URTP emission with the delay time exceeding 23 s (lifetime of ∼1.48 s) can be clearly identified with the naked eye. The presence of self-protective covalently crosslinked frameworks with codoped N and P atoms and the formation of interdot/intradot hydrogen-bonded skeletons are suggested to account for the observed URTP phenomena. The NP-CPDs exhibit excellent water solubility and color conservation during repeated liquid–solid transformations, thus allowing for a fast and large-scale ink-jet print of such nanodots to encode information. Consequently, the potential application of such NP-CPDs in anticounterfeiting and information encryption is demonstrated. This study provides a facile strategy to prepare URTP nanostructures for intriguing applications.

Developing advanced technologies to address the bacterial associated infections is an urgent requirement for metallic implants and devices. Here, we report a novel phosphonate/quaternary amine block polymer as the high-efficiency antibacterial coating for metallic substrates. Three pDEMMP-b-pTMAEMA block polymers that bearing identical phosphonate segments (repeat units of 15) but varied cationic segments (repeat units of 8, 45, and 70) were precisely prepared. Stable cationic polymer coatings were constructed on TC4 substrates based on the strong covalent binding between phosphonate group and metallic substrate. Robust relationship between the segment chain length of the polymer coating and the antibacterial property endowed to the substrates have been established based on quantitative and qualitative evaluations. Results showed that the antibacterial rate of the modified TC4 surface were 95.8 % of S. aureus and 92.9 % of E. coli cells attached. Interestingly, unlike the cationic free polymer or cationic hydrogels, the surface anchored cationic polymers do compromise the viability of the attached C2C12 cells but without significant cytotoxicity. In addition, the phosphonate/quaternary amine block polymers can be easily constructed on titanium, stainless steel, and Ni/Cr alloy with significantly improved antibacterial property, indicating the generality of the block polymer for surface antibacterial modification of bio-metals.

In this paper, an implementation method of high sensitivity thin film fiber optic pressure sensor based on air blowing method is proposed. The utility model is characterized in that a film ultra-thin microbubble structure is firstly formed on the surface of the AB epoxy glue solution by using high-pressure air, and then the film portion of the end portion of the microbubble is transferred to a single-mode fiber head with a hollow glass tube at the top. Finally, a thin film structure fiber Fabry-Perot fiber pressure sensor is formed. The experimental results show that the thickness of the thin film layer at the end of the FP sensor is only 16 μm. Correspondingly, the maximum pressure sensitivity can reach 263.15 pm/kPa. Meanwhile, due to the decrease of film thickness, the sensor's resistance to temperature interference is improved. The prepared fiber Fabry-Perot pressure sensor has the advantages of ultra-thin film thickness, high-pressure sensitivity, low cost and good repeatability. Therefore, it has good application value in high sensitivity pressure and sound wave detection.

Active metasurfaces, in which the optical property of a metasurface device can be controlled by external stimuli, have attracted great research interest recently. For optical switching and modulation applications, high-performance active metasurfaces need to show high transparency, high power efficiency, as well as ultrafast switching and large-scale fabrication capability. This paper reports Au/VO2-based active metasurfaces meeting the requirements above. Centimeter-scale Au/VO2 metasurfaces are fabricated by polystyrene sphere colloidal crystal self-assembly. The devices show optical modulation on-off ratio up to 12.7 dB and insertion loss down to 3.3 dB at 2200 nm wavelength in the static heating experiment, and ΔT/T of 10% in ultrafast pump-probe experiments. In particular, by judiciously aligning the surface plasmon resonance wavelength to the pump wavelength of the femtosecond laser, the enhanced electric field at 800 nm is capable to switch off the extraordinary optical transmission effect at 2200 nm in 100 fs time scale. Compared to VO2 thin-film samples, the devices also show 50% power reduction for all-optical modulation. Our work provides a practical way to fabricate large-scale and power-efficient active metasurfaces for ultrafast optical modulation.

The use of fingerprint for biometric identification is one of the most prevalent authentication methods applied today in smartphones. In the course of pursuing narrow-bezel and full-screen display, the under-display fingerprint sensor is considered to be a user-friendly and practical solution for newer models of smartphone. While under-display optical fingerprint sensor has been commercially available in various smartphones, it demonstrates limitations such as sensitivity to humidity and contaminations including oil and water as well as easy to spoof. Ultrasonic fingerprint sensing has been proved to be able to overcome these limitations. In this study, P(VDF-TrFE) piezoelectric polymer-based transducer was reported, for the first time, for under-display ultrasonic fingerprint sensing applications. In specific, a 40 MHz ultrasonic transducer using a layer of $10~\mu \text{m}$ thick P(VDF-TrFE) thin-film was designed, fabricated, and characterized. The under-display ultrasonic fingerprint sensing capability of the prototyped transducer was experimentally validated using phantoms of real fingerprint. Electronic images of fingerprint with resolution of $500\times500$ DPI were obtained through under-display ultrasonic fingerprint sensing tests. The lateral resolution of the transducer was calculated to be $\sim ~70~\mu \text{m}$ . The results of this study illustrate promising advances in under-display ultrasonic fingerprint sensing applications.

ZnO has been widely used as piezoelectric materials in bulk acoustic resonators, especially in shear-mode film bulk acoustic resonators (FBAR). In this paper, we studied the effect of c-axis tilted ZnO thin film on shear mode FBAR in liquid environment. Mechanical impedances of FBARs are compared between shear-mode and longitudinal-mode wave due to their different orientations of ZnO thin film. It is found ZnO thin film with 43° c-axis tilted angels induces quasi-shear-mode acoustic wave only. The Q values of FBAR with 43° c-axis tilted ZnO are 256.94 in air at 0.8148 GHz, and 34.34 in water at 0.814 GHz, respectively. The shifts of the resonant frequencies are proportional to the square root of the product of viscosity and density of liquid medium, which is consistent with Kanazawa-Gordon theory and verified by actual experiment.

The evolution of sliver defect in a Ni-based single crystal superalloy was explored by casting samples with a similar geometry of the airfoil section of a turbine blade using optical microscope and electron backscattered diffraction. It was found that the sliver generally initiated from 1 to 2 tertiary dendrites at the diverging boundary between the mold wall and matrix. All slivers were tilt from matrix along the [001] and some of them rotated relative to the matrix on the plane perpendicular to the solidification direction. During solidification sliver in most castings grew with a fixed orientation. All slivers can extend along the solidification direction to the top of the casting. Most of the sliver defects showed constant width and did not extend on the casting surface. However, the sliver with large misorientation to matrix on the cross section perpendicular to the solidification direction extended on the casting surface and into the casting quickly.

Amorphous iron phosphate (FePO 4 ) has attracted enormous attention as a promising cathode material for sodium-ion batteries (SIBs) because of its high theoretical specific capacity and superior electrochemical reversibility. Nevertheless, the low rate performance and rapid capacity decline seriously hamper its implementation in SIBs. Herein, we demonstrate a sagacious multi-step templating approach to skillfully craft amorphous FePO 4 yolk-shell nanospheres with mesoporous nanoyolks supported inside the robust porous outer nanoshells. Their unique architecture and large surface area enable these amorphous FePO 4 yolk-shell nanospheres to manifest remarkable sodium storage properties with high reversible capacity, outstanding rate performance, and ultralong cycle life.

This article presents new optical pixel sensors that are based on hydrogenated amorphous silicon thin-film transistors (a-Si:H TFTs) for detecting secondary color optical signals to increase the number of colors of sensed light. Three types of series-connected structure with different photo TFTs enable the sensors to receive secondary color optical input signals that combine any two primary colors, such as magenta (blue and red), cyan (green and blue), and yellow (red and green). The secondary color optical sensors also prevent from being affected by light of a single color to integrate with primary color optical sensors for realizing a six-color sensing mechanism. Moreover, only one photo TFT is used to suppress the effect of ambient white light by compensating photocurrents without increasing the complexity of the proposed sensor structure. The measurements demonstrate that the difference in the output voltages is 15.6 V even under ambient white light with an intensity of 10000 lux, proving that the proposed sensor can yield significantly different sensing results with and without an optical input signal under intense ambient white light. Thus, the proposed sensors increase the number of sensed color light that can be integrated with a large TFT-LCD panel for multiuser interaction.

Electronic phase separation in complex oxides is the inhomogeneous spatial distribution of electronic phases, involving length scales much larger than those of structural defects or nonuniform distribution of chemical dopants. While experimental efforts focused on phase separation and established its correlation with nonlinear responses under external stimuli, it remains controversial whether phase separation requires quenched disorder for its realization. Early theory predicted that if perfectly “clean” samples could be grown, both phase separation and nonlinearities would be replaced by a bicritical-like phase diagram. Here, using a layer-by-layer superlattice growth technique we fabricate a fully chemically ordered “tricolor” manganite superlattice, and compare its properties with those of isovalent alloyed manganite films. Remarkably, the fully ordered manganite does not exhibit phase separation, while its presence is pronounced in the alloy. This suggests that chemical-doping-induced disorder is crucial to stabilize the potentially useful nonlinear responses of manganites, as theory predicted.

Chiral nanophotonic devices are promising candidates for chiral molecule sensing, polarization of diverse nanophotonics, and display technologies. Active chiral nanophotonic devices, where the optical chirality can be controlled by an external stimulus has triggered great research interest. However, efficient modulation of the optical chirality has been challenging. Here, we demonstrate switching of the extrinsic chirality by applied magnetic fields in a magnetoplasmonic metasurface device based on a magneto-optical oxide material, Ce1Y2Fe5O12 (Ce:YIG). Due to the low optical loss and strong magneto-optical effect of Ce:YIG, we experimentally demonstrated giant and continuous far-field circular dichroism (CD) modulation by applied magnetic fields from -0.6 ± 0.2° to +1.9 ± 0.1° at 950 nm wavelength under glancing incident conditions. The far-field CD modulation is due to both magneto-optical circular dichroism and near-field modulation of the superchiral fields by applied magnetic fields. Finally, we demonstrate magnetic-field-tunable chiral imaging in millimeter-scale magnetoplasmonic metasurfaces fabricated using self-assembly.

A controllable self-assembled growth using molecular beam epitaxy (MBE) of dense, uniform, and high-aspect-ratio InGaN nanorods (NRs) is achieved through regulating the Ga/In flux ratio and employing high Miller index planes of patterned sapphire substrates (PSSs). It is clearly demonstrated that both the low Ga/In flux ratio and high Miller index plane of PSS patterns facilitate the three-dimensional growth mode for InGaN NRs and simultaneously suppress NR coalescence. A lower Ga/In flux ratio favors a higher density, a larger aspect ratio, and a smaller coalescence degree of InGaN NRs through enhancing axial growth and inversely suppressing radial growth. The specific surface structures of high Miller index planes, e.g., the well-organized step-terrace and irregular bulge structures, critically affect the morphology, dimensions, density, and crystallographic orientation of MBE self-assembled NRs. In particular, the narrow and ordered step-terrace structure in the C3-plane-(4 5[combining macron] 1 38) plane-on a hexagonal pyramid favors the highest density, largest aspect ratio, and best uniformity of semipolar InGaN NRs, thus contributing to optimal photoluminescence performance. A thorough understanding of the mechanism of the effect of the Ga/In flux ratio and crystallographic plane on the MBE self-assembled growth behaviour of InGaN NRs was gained through experimental and theoretical exploration. This work contributes towards a deep understanding of the MBE self-assembled growth mechanism and controllable fabrication of dense, well-separated, and uniform InGaN NRs, thus contributing to the enhanced performance of NR-based optoelectronic devices.

Synthesis of 2D materials with different morphologies is of significance to reveal their morphology-dependent properties and further explore their morphology-dependent applications. This work reports the synthesis of 2D red phosphorus nanosheets (RPNSs) with different thicknesses by means of a phosphorus-amine method together with regulated electrophilicity of the solution. With graphene as the support, the RPNSs produced in 0.01 m HCl feature a unique 2D nanostructure, uniform distribution, and excellent electrochemical performance. Originating from the reacted characteristics between phosphorus and amine, the interaction of aniline with the RPNSs is clarified theoretically and experimentally by means of density functional theory, X-ray photoelectron spectroscopy, and voltammetry. A covalent bond is confirmed to be formed during the deprotonation of aniline and its binding energy reaches -2.31 eV. Stemming from such an adsorption process, different aromatic amines (e.g., p-nitroaniline, p-phenylenediamine) are sensitively and selectively monitored on the RPNSs. Consequently, this work provides a new way to clarify morphology-dependent properties and applications of novel 2D materials.

Two-dimensional (2D) ferromagnetic materials have been discovered with tunable magnetism and orbital-driven nodal-line features. Controlling the 2D magnetism in exfoliated nanoflakes via electric/magnetic fields enables a boosted Curie temperature (TC) or phase transitions. One of the challenges, however, is the realization of high TC 2D magnets that are tunable, robust and suitable for large scale fabrication. Here, we report molecular-beam epitaxy growth of wafer-scale Fe3+XGeTe2 films with TC above room temperature. By controlling the Fe composition in Fe3+XGeTe2, a continuously modulated TC in a broad range of 185–320 K has been achieved. This widely tunable TC is attributed to the doped interlayer Fe that provides a 40% enhancement around the optimal composition X = 2. We further fabricated magnetic tunneling junction device arrays that exhibit clear tunneling signals. Our results show an effective and reliable approach, i.e. element doping, to producing robust and tunable ferromagnetism beyond room temperature in a large-scale 2D Fe3+XGeTe2 fashion.

Graphene electrochemistry is dependent on the quality of produced graphene. Ultrasonic exfoliation of graphite in a solvent with aid of sodium salts is believed to be a convenient method to prepare high-quality graphene layers, although the effect of sodium salts on the yields of exfoliated graphene and electrochemistry of graphene have not been clearly clarified. Herein, different sodium salts (e.g., sodium citrate, sodium phosphate, and sodium pyrophosphate) with different anions are added during ultrasonic exfoliation of graphite in N-methyl-2-pyrrolidone (NMP). Sodium pyrophosphate improves the most efficiently the graphene yield and decreases the number of graphene layers, leading to the highest defect content. On these defect-rich graphene layers, the redox response of K3[Fe(CN)6] exhibits the fastest electron-transfer rate constant. Their active areas are also the largest, as revealed using rotating ring disk electrode and cyclic voltammetry. Moreover, the oxidation signals of biomolecules (e.g., dopamine, uric acid, xanthine, and hypoxanthine), phenolic pollutants (e.g., 4-chlorophenol and 4-nitrophenol), and toxic colorants (e.g., ponceau 4R and rhodamine B) are the mostly enhanced. This work proposes a novel way to synthesize defect-rich exfoliated 2D materials and further to construct universal interfaces for different electrochemical applications.

Although copper oxide high-temperature superconductors constitute a complex and diverse material family, they all share a layered lattice structure. This curious fact prompts the question of whether high-temperature superconductivity can exist in an isolated monolayer of copper oxide, and if so, whether the two-dimensional superconductivity and various related phenomena differ from those of their three-dimensional counterparts. The answers may provide insights into the role of dimensionality in high-temperature superconductivity. Here we develop a fabrication process that obtains intrinsic monolayer crystals of the high-temperature superconductor Bi2Sr2CaCu2O8+δ (Bi-2212; here, a monolayer refers to a half unit cell that contains two CuO2 planes). The highest superconducting transition temperature of the monolayer is as high as that of optimally doped bulk. The lack of dimensionality effect on the transition temperature defies expectations from the Mermin–Wagner theorem, in contrast to the much-reduced transition temperature in conventional two-dimensional superconductors such as NbSe2. The properties of monolayer Bi-2212 become extremely tunable; our survey of superconductivity, the pseudogap, charge order and the Mott state at various doping concentrations reveals that the phases are indistinguishable from those in the bulk. Monolayer Bi-2212 therefore displays all the fundamental physics of high-temperature superconductivity. Our results establish monolayer copper oxides as a platform for studying high-temperature superconductivity and other strongly correlated phenomena in two dimensions. Transport and scanning tunnelling microscopy studies of freestanding monolayers of an unconventional layered copper oxide establish that the superconducting properties of copper oxides are not changed in the 2D limit.

Environmentally friendly pesticide delivery systems have drawn extensive attention in recent years, and they show great promise in sustainable development of agriculture. We herein report a multifunctional nanoplatform, carboxymethyl chitosan modified carbon nanoparticles (CMC@CNP), as the carrier for emamectin benzoate (EB, a widely used insecticide), and investigate its sustainable antipest activity. EB was loaded on CMC@CNP nanocarrier via simple physisorption process, with a high loading ratio of 55.56%. The EB@CMC@CNP nanoformulation showed improved solubility and dispersion stability in aqueous solution, which is of vital importance to its practical application. Different from free EB, EB@CMC@CNP exhibited pH-responsive controlled release performance, leading to sustained and steady EB release and prolonged persistence time. In addition, the significantly enhanced anti-UV property of EB@CMC@CNP further ensured its antipest activity. Therefore, EB@CMC@CNP exhibited superior pest control performance than free EB. In consideration of its low cost, easy preparation, free of organic solution, and enhanced bioactivity, we expect, CMC@CNP will have a brilliant future in pest control and green agriculture.

Molybdenum complexes are versatile and efficient for liquid phase olefin epoxidation reactions. Rational design of catalysts is critical to achieve high atom efficiency during epoxidation processes. Although liquid phase epoxidation has been a popular topic for decades, three key issues, (a) rational control of morphology of molybdenum nanoparticles, (b) manipulating metal-support interaction and (c) altering electronic configuration at molybdenum center remains unsolved in this area. Therefore, in this paper, we have critically revised recent research progress on heterogeneous molybdenum catalysts for facile liquid phase olefin epoxidation in terms of catalyst synthesis, surface characterization, catalytic performance and structure-function relationship. Furthermore, plausible reaction mechanisms will be systematically discussed with the aim to provide insights into fundamental understanding on novel epoxidation chemistry.

We propose a new optical biosensor based on photonic spin Hall effect (PSHE) for detection of DNA hybridization. This device consists of BK7 prism, Ag, SiO2, Au and graphene-MoS2 heterostructure which produces waveguide coupled surface plasmon resonance (WCSPR) effect to enormously enhance PSHE. The adsorption of graphene-MoS2 heterostructure to biomolecules changes the refractive index of the sensing medium, thereby affecting spin-dependent splitting in PSHE. The 2 × 2 transfer matrix method is applied to calculate the generalized Fresnel reflection and we deduce the reflected light shifts in PSHE. We study the correlation between spin-dependent displacements and the refractive index variations of sensed solution to obtain the highest sensitivity in the proposed sensor. However, the PSHE exists in the proposed biosensor is extremely weak, so a signal enhancement technology called weak measurement is adopted to amplify the PSHE shift. Thus, the proposed biosensor can successfully detect the hybridization of probe DNA with target DNA. These results may provide practical applications for PSHE in biological monitoring, medical diagnosis, and food safety.

Phototherapy, including photothermal and photodynamic therapy, has attracted extensive attention due to its noninvasive nature, low toxicity, and high anticancer efficiency. The charge-separation mechanism of plasmon-induced resonance energy transfer (PIRET) has been increasingly employed to design nanotheranotic agents. Herein, we developed a novel and smart PIRET-mediated nanoplatform for enhanced, imaging-guided phototherapy. Prussian blue (PB) was incorporated into a Au@Cu2O nanostructure, which was then assembled with poly(allylamine) (PAH)-modified black phosphorus quantum dots (Au@PB@Cu2O@BPQDs/PAH nanocomposites). The hybrid nanosystem exhibited great absorption in the near-infrared region, as well as the ability to self-supply O2 by catalyzing hydrogen peroxide and convert O2 into singlet oxygen (1O2) under 650 nm laser light (0.5 W/cm2) irradiation. In vitro and in vivo assays showed that the generated heat and toxic 1O2 from Au@PB@Cu2O@BPQDs/PAH nanocomposites could effectively kill the cancer cells and suppress tumor growth. Moreover, the unique properties of the PB-modified nanosystem allowed for synergistic therapy with the aid of T1-weighed magnetic resonance imaging (T1-weighted magnetic resonance imaging) and photoacoustic imaging. This study presented a suitable way to fabricate smart PIRET-based nanosystems with enhanced photothermal therapy/photodynamic therapy efficacy and dual-modality imaging functionality. The great biocompatibility and low toxicity ensured their high potential for use in cancer therapy.

In this work, three azole-based ternary deep eutectic solvents (DESs) were designed for highly efficient absorption of NH3 by utilizing the weak acidity of azoles. Specifically, the DESs are compos...

The cancer cell membrane (CCM) is widely used for nanomedicine encapsulation to improve their tumor-targeting ability. However, few researches are focused on drug release process and mechanism of these composite. Cell membrane fusion (two separate lipid membranes merge into a single continuous bilayer), one of the most fundamental processes in biology could be promoted by heating. Thus, in this manuscript, CCM was exploited as the gate keeper and tumor-targeting moiety of anticancer drug-loaded mesoporous silica nanoparticles (MSN). In addition, the drug release process and mechanism based on cell membrane fusion were studied. The loaded drugs included indocyanine green (ICG), a FDA-approved near-infrared photothermal agent for clinical applications, and doxorubicin (DOX), a chemotherapy drug. By coating CCM on drug-loaded MSN, the keeper could prevent unexpected drug leaking during the circulation and provide tumor targeting based on its specific recognition function. After arriving tumor tissue post-tail vein injection, the tumor position is irradiated by 808 nm light to trigger light–thermal conversion process of ICG to heat the composite (DOX-ICG@MSN@CCM) and promote cell membrane fusion between the encapsulated CCM and targeted tumor cell membrane. Such process can enhance the uptake efficacy of DOX-ICG@MSN@CCM to tumor cells. Furthermore, ICG could provide a synergistic photothermal therapy activity with DOX.

Biocompatible and biodegradable magnesium (Mg) and its alloys possess excellent potential as orthopedic implant biomaterials, but they corrode too quickly inside the human body to maintain such functions as supporting and fixation. In this study, we have successfully prepared a composite biomedical material with Mg as the substrate and a multilayered coating on the metal, which contains a chemical conversion layer of fluoride or phosphate, an adhesion layer, and a layer of biodegradable polylactic acid (PLA). The recorded weight loss and the release of ionic magnesium (Mg2+) in the simulated body fluid (SBF) demonstrate that the corrosion rate of the protected Mg has been reduced to 1/10 that of the unprotected bare Mg. The corrosion rate of the protected Mg can be adjusted with either the chemical conversion type or the thickness of the PLA layer. The bare and the protected Mg has been manufactured as an implant for bone defect repair of Sprague–Dawley rats. The X-ray and micro-CT images show an improved...

This paper reports a novel routine for the fabrication of a polycaprolactone-derived (PCL-derived) photocured material cross-linked by pentaerythritol tetra (PETMP) with enhanced mechanical property and excellent biocompatibility. The photocured material is cross-linked via UV irradiation through thiol-ene “click” chemistry. The main novelty of this technique is the facile fabrication of high-resolution patterns (∼5 μm) using photolithography, and without adding photo-initiators. The photocured material is studied regarding to its thermal property, mechanical property and cytocompatibility. DSC and DMA suggest that the flexibility and toughness of PCL-derived photocured material have improved. Accordingly, the PCL-derived photocured material achieves enhanced mechanical property (with the increase of PCL segment content from 0 to 38.0%, the photocured samples monotonically increased their breaking strength from 0.62 to 3.10 MPa and Young’s modulus from 1.39 to 9.22 MPa). Due to the incorporation of the PCL-derived copolymer, the material shows excellent affinity to cells, which is demonstrated by the cell proliferation and release of LDH. The hemolysis ratio of PCL-derived photocured materials is all

We propose a refractive index sensing structure based on Mach–Zehnder interferometer (MZI) with a hybrid silica/polymer waveguide. Due to the thermo-optic (TO) effects of polymer and silica, the refractive index of sample can be measure by an integrated circuit. We discuss the design principle of the refractive index sensing waveguide and give its equivalent circuit to explain the sensing process. The sensitivity of MZI waveguide achieves 5556 °C/RIU which has a compact size of 10 μm × 6 mm. The sensing structure can be applied in a highly compact biosensing system and possess a great potential in point-of-care diagnostics and healthcare applications.

We study the spin hall effect of light (SHEL) in prism coupling configuration with magneto-optical (MO) material and bimetallic film which is called MOSHEL. Compared with single gold film, the surface plasmon resonance (SPR) with the bimetallic film can achieve minimum reflectivity and the difference between transverse shifts with opposite magnetic field directions can achieve 13 μm at resonance angle. By adjusting the thickness of magneto-optical layer and bimetallic film, we find that both SPR and SHEL can be modulated by the magnetic field. Base on this we propose that MOSHEL can be enhanced by MOSPR for the first time.

Understanding the relative permeability characteristics of coal in a gas-water system is crucial for coalbed methane development. Due to a lack of experimental information on the gas-water relative permeability of coal, the relative permeability of the low-rank coals in the Erlian Basin in the north of China was investigated under different conditions using the unsteady-state method. The studied coals are dominated by huminite with high moisture content, volatile yield, and low ash yield. The pore sizes of the coals feature a bimodal pattern distribution with a higher left peak of approximately 10–100 nm and a relatively lower right peak of approximately 10000 nm. The measurement of mercury intrusion-extrusion hysteresis also suggests that ink bottle-shaped pores are possibly developed within the coals. The results from relative permeability tests with methane (CH4) and water depend on the pore structure, coal wettability, confining pressure, and pressure difference in the coal. The results show that a definite correlation does not exist between relative permeability and porosity in the low-rank coal. However, macropore porosity rather than the whole range of the porosity is the most likely property affecting the water relative permeability, whereas the effect of pore size on gas relative permeability varies along with a broader range. It has been observed that the low-rank coal with higher water wettability exhibits lower water relative permeability, narrower two-phase span, higher gas relative permeability, and irreducible water saturation. With the increase in the confining pressure, both the methane and water relative permeabilities decrease, while the ratio of relative permeability (krw/krg) increases. This suggests that the confining pressure has less influence on water relative permeability than that on gas. As the pressure difference increases under the same effective stress, the residual water saturation in the low-rank coals decreases, and the associated two-phase span increases. Water relative permeability obviously increases above the crossover point water saturation, whereas gas relative permeability increases below the crossover point water saturation.

The lack of blood compatibility and antifouling ability is still one of the challenges of bare metallic implants and devices for biomedical applications. Here, based on the strong binding affinity of the phosphonic group on metallic substrates and excellent antifouling ability of zwitterionic materials, we reported the rational design of zwitterionic–phosphonic copolymers for efficient antifouling surface modification of diverse biomedical metals. Firstly, nine copolymers with a wide range of mole ratios between the zwitterionic and phosphonic components (from 10 : 90 to 99 : 1) were precisely prepared via conventional radical copolymerization. The XPS result revealed that the copolymers, even if only 1% of the phosphonic component was present, were able to bind onto the titanium alloy substrates. Water contact angle measurement showed that the more zwitterionic component in the coating copolymer, the better the surface wettability of the titanium alloy substrates. Systematic antifouling evaluation (protein adsorption, platelet adhesion, bacterial adhesion, and cell adhesion tests) results consistently indicated that the copolymers bearing the zwitterionic components, ranging from 20 to 95%, can efficiently confer perfect antifouling ability to the titanium alloy substrates, establishing a robust relationship between the composition of the copolymer and the surface antifouling property conferred to the titanium alloy substrates. In addition, the ability of the zwitterionic–phosphonic copolymers to improve the antifouling ability of other biomedical metals (pure Ti and stainless steel) and devices (scalpels) was clearly demonstrated, indicating that the zwitterionic–phosphonic copolymers could serve as general antifouling coating materials for biomedical metals.

Three polymorphic copper carboxylate-phosphonates are reported, namely, α-Cu(4-cnappH)(H2O) (α-Cu-1), α-Cu(4-cnappH)(H2O)·0.5H2O (α-Cu-2) and β-Cu(4-cnappH)(H2O) (β-Cu), where 4-cnappH3 is (4-carboxynaphthalen-1-yl)phosphonic acid. All show layer structures but with different layer topologies. The layer topologies of the α-phases are similar, where the distorted {CuO4} planes and {PO3C} tetrahedra are corner-shared forming an inorganic layer containing 8- and 16-member rings. In β-Cu, double chains made up of corner-sharing {CuO5} and {PO3C} are crossed-linked through edge-sharing of the {CuO5} square pyramids to form an inorganic layer containing 4- and 8-member rings. The uncoordinated carboxylate groups are protonated and are involved in the interlayer hydrogen bonds in all cases. Antiferromagnetic interactions are dominant in all cases. Compounds α-Cu-1, α-Cu-2 and β-Cu can be exfoliated in THF resulting in 2D nanosheets of mainly two-layer thickness. Proton conductivity measurements reveal that the proton conduction is more favorable in α-Cu-2 than in α-Cu-1, but exfoliation into nanosheets decreases the conductivity.

Hydrothermal reactions of the multitopic ligand 1-hydroxy-1-(piperidin-4-yl)methylidenebisphosphonic acid (hpdpH4) with cobalt or nickel sulfates afforded two new isostructural metal phosphonates, M3II(hpdpH)2(H2O)6·4H2O [M = Co (Co-10H2O), Ni (Ni-10H2O)]. Their structures consist of parallel diamond chains of three MO6 octahedra bridged by the PO3C tetrahedra. Six of the seven oxygen atoms of the ligand are involved in coordination; for two ligands that amounts to 12 bonds for 3 MO6 and the remaining six are occupied by terminal water molecules. In addition, four water molecules sit in between the chains providing H-bonds to the formation of a 3D-net. Thermal analyses show identical two-step dehydration processes involving first the departure of six water molecules followed by the remaining four. A detailed study of the ac- and dc-magnetization as a function of temperature, field and frequency reveals associated drastic changes. The virgin form Co-10H2O is a paramagnet while its partial dehydrated form Co-4H2O is an antiferromagnet displaying canting below TN = 4.7 K and the fully dehydrated form Co is a ferrimagnet (TC = 12 K). Ni-10H2O and Ni-4H2O exhibit long-range ordered antiferromagnetism (TN = 2.7 and 4.0 K, respectively) and also become ferrimagnets (TC = 9.4 K) when fully dehydrated to Ni. The dehydrated samples can be fully rehydrated with the complete recovery of both the structures and magnetic properties.

A kind of fiber PH sensor coated with PANI (polyaniline) on the surface of LPFG (long-period fiber grating) has been developed in the work. PANI film was nurtured in the solution by in-situ chemical oxidative polymerization and the growth process of the PH sensitive film was traced by an optical spectrum analyzer to optimize the response of the sensor. The RI and optical properties of PANI change regularly in the PH range of 2-12, which is the basic principle of LPFG coated with PANI sensing material for PH measurement. Though the experiment, the sensor can achieve a high sensitivity of 152pm/ph. Besides, other performances of the sensor, such as response time, temperature stability, reversibility and long-term stability were studied in the experiment. As a result, The PANI-LPFG sensor has such advantages as fast response speed, excellent temperature stability, low cost, easy to be used, and continuous measurement of the environment.

The optimal therapy effect of tumors is frequently restricted by the dense extracellular matrix (ECM) and anoxia. Herein, an intelligent BPNs-Arg-GOx@MnO2 (BAGM) nanozyme is innovatively designed as a multimodal synergistic therapeutic paradigm that possesses both nitric oxide (NO) self-supplying and ECM degradation properties to reinforce the therapy effect by a tumor microenvironment (TME)-activatable cyclic cascade catalytic reaction. This theranostic nanoplatform is constructed by using polyethyleneimine-modified black phosphorus nanosheets as a "fishnet" to attach l-Arginine (l-Arg) and glucose oxidase (GOx) and then depositing mini-sized MnO2 nanosheets (MNs) on the surface by a facile situ biomineralization method. As an intelligent "switch", the MNs can effectively trigger the cascade reaction by disintegrating intracellular H2O2 to release O2. Then, the conjugated GOx can utilize O2 production to catalyze intracellular glucose to generate H2O2, which not only starves the tumor cells but also promotes oxidation of l-Arg to NO. Thereafter, matrix metalloproteinases will be activated by NO production to degrade the dense ECM and transform matrix collagen into a loose state. In turn, a loose ECM can enhance the accumulation of the BAGM nanozyme and thereby reinforce synergistic photothermal therapy/starvation therapy/NO gas therapy. Both in vitro and in vivo results indicate that the TME-tunable BAGM therapeutic nanoplatform with cascade anticancer property and satisfactory biosecurity shows potential in nanomedicine.

Permanent magnet biased axial-radial magnetic bearing (ARMB) can realize axial and radial suspension simultaneously. It has a compact configuration with the volume and weight reduced. However, its magnetic field distribution is quite complicated, its bias and control magnetic field are coupled. In order to design the magnetic bearing accurately, this paper divides the leakage and soft magnetic material routes according to the 2D FE simulation, establishes the accurate magnetic circuit including the leakage and soft magnetic material reluctance. The circuit can be used to observe the flux distribution in each route, verify and regulate the magnetic bearing structure parameter, so the FE computation efforts of the basic structure parameter are significantly reduced. An experimental sample was designed, 3D FE simulation and experiments were processed to test the prototype. The results confirm that the design method is reasonable and correct.

To prevent the illegal discharge of metal plating wastewater (MPW), it is necessary to explore a monitoring method that could achieve the identification of MPW in natural water bodies. Fluorescence excitation-emission matrix-parallel factor (EEM-PARAFAC) analysis might be a promising tool for the detection of MPW. However, before conducting the practical monitoring, the apparent fluorescence features of different kinds of MPW must be first understood. In this study, six types of MPW (576 samples) from ten metal plating plants were collected and their fluorescence fingerprints (FFs) were characterized by EEM-PARAFAC analysis. Results showed that pretreatment wastewater (PTW), copper-contained electroplating wastewater (Cu-EPW), nickel-contained electroplating wastewater (Ni-EPW), copper-contained electroless wastewater (Cu-ELW), nickel-contained electroless wastewater (Ni-ELW), and metal plating effluent (MPE) presented one, three, one, one, two, and three types of FFs, respectively. Among them, three individual fluorescent components were identified in Ni-EPW and two were decomposed in other kinds of MPW. Owing to the discrepancies of production processes, electroplating additives, wastewater treatment techniques, and management levels, different metal plating plants owned different FFs. By spectral comparison, the tyrosine-like components in PTW and Ni-ELW might derived from some phenolic and benzenesulfonic acidic compounds. Fluorescent component similarity analysis indicated that EEM-PARAFAC technique could distinguish the raw and treated MPW. This study not only constructed the first FF database for MPW, but also provided valuable guidance for their practical monitoring in aquatic environment.