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Colloidal clusters with well-controlled shapes have attracted extensive interest in the fields of materials, chemistry, physics, and biology. This communication reports the controllable fabrication of photoresponsive colloidal clusters with a wide range of adjustable sizes and complex architectures through an approach of microsphere formation and fusion. The clusters of colloidal spheres were obtained via adding ethanol dropwise into a tetrahydrofuran solution of an isosorbide-based azo compound (IAC-4). In the process, the colloidal spheres with soft and sticky shells were first formed in the dispersion. After stirring at an appropriate rate and time, clusters composed of controlled numbers of colloidal spheres were obtained. With increasing stirring time, the colloidal spheres in the clusters underwent fusion transforming into a range of structures with particular architectures. The structure formation, evolution and control were investigated by scanning electron microscopy (SEM) and dynamic light scattering (DLS). Under linearly polarized light irradiation, colloidal spheres in the clusters in the solid state were observed to be stretched along the direction of electric-field oscillation and these clusters were thus transformed into complex particles with unique morphologies. This exploration can lead to a new methodology to effectively fabricate colloidal clusters with complex architectures and shed new light on colloidal packing and organization under the driving forces of extrinsic energy input.

Rechargeable Li-CO 2 batteries have attracted extensive attention owing to their high theoretical energy density (1876 W h Kg -1 ). However, their practical application is hindered by large polarization, low coulombic efficiency, and cathode degradation. The electrochemical performance of Li-CO 2 batteries is significantly affected by the thermodynamic stability and reaction kinetics of discharge products. Although advances have been achieved in cathode design and electrolyte optimization over the past decade, the reaction mechanism of the CO 2 cathode has not yet been clear. In this review, various reaction mechanisms of CO 2 reduction and evolution at the cathode interface are discussed, including different reaction routes under mixed O 2 /CO 2 and pure CO 2 environments. Furthermore, the regulating strategies of different discharge products, including Li 2 CO 3 , Li 2 C 2 O 6 , and Li 2 C 2 O 4 , are summarized to decrease the polarization and improve the cycling performance of Li-CO 2 batteries. Finally, the challenges and perspectives are discussed from three aspects: reaction mechanisms, cathode catalysts, and electrolyte engineering, offering insights for the development of Li-CO 2 batteries in the future.

Acupoints are the local initial response sites of acupuncture therapeutic effects. As a biomarker, histamine is released into the acupoint region and plays its role concurrently as acupuncture needles are inserted into acupoints. Hence, real-time monitoring of histamine at acupoints is important to elucidate the effectiveness of the acupoint-activation process in acupuncture. Therefore, we developed highly sensitive acupuncture/Au particles/graphene biosensors by electrodeposition, brushing, and annealing methods based on bare acupuncture needles. We achieved a histamine detection limit of approximately 4.352 (±3.419) × 10 -12 mol L -1 and good sensitivity of approximately 6.296 (±3.873) μA μM -1 , with satisfactory specificity, repeatability, and stability in vitro , rendering them more competitive and suitable for real-time monitoring in vivo without causing additional damage. Subsequently, we conducted real-time histamine monitoring at non-acupoint and acupoint PC6 in rats, respectively. Our results showed minimal changes at the non-acupoint, whereas a trend of initial increase followed by a decrease was observed at acupoint PC6. The change in histamine concentration at acupoint PC6 reflected its involvement in the acupoint-activation procedure. Moreover, its peak position at ∼18 min could provide guidance for optimizing needle retaining time for maximum therapeutic effect. This work presents the first real-time in vivo monitoring of histamine at acupoints with high sensitivity and underscores the specificity of histamine release between non-acupoint and acupoint PC6, demonstrating great potential for elucidating the acupoint-activation mechanisms in acupuncture. Additionally, this work expands the application of nanomaterials in the integration of medicine and engineering, which is an important aspect of the future development of materials science.

The electrochemical reduction of carbon dioxide (CO 2 RR) to carbon monoxide represents a cost-effective pathway towards realizing carbon neutrality. To suppress the hydrogen evolution reaction (HER), the presence of alkali cations is critical, which can however lead to precipitate formation on the electrode, adversely impacting the device stability. Employing pure water as the electrolyte in zero-gap CO 2 electrolyzers can address this challenge, albeit at the cost of diminished catalyst performance due to the absence of alkali cations. In this study, we introduce a novel approach by implementing amino modifications on the catalyst surface to mimic the function of alkali metal cations, while simultaneously working in pure water. This modification enhances the adsorption of carbon dioxide and protons, thereby facilitating the CO 2 RR while concurrently suppressing the HER. Utilizing this strategy in a zero-gap CO 2 electrolyzer with pure water as the anolyte resulted in an impressive carbon monoxide faradaic efficiency (FE CO ) of 95.5% at a current density of 250 mA cm -2 , while maintaining stability for over 180 hours without any maintenance.

Two-dimensional (2D) Janus trihalides have attracted widespread attention due to their potential applications in spintronics. In this work, the valley polarization of MoSe 2 at the K' and K points can be modulated by Ni 2 Cl 3 I 3 , a new 2D Janus trihalide. The Ni 2 Cl 3 I 3 /MoSe 2 heterostructure has an in-plane magnetic anisotropy energy (IMA) and is characterized by three distinct electronic structures: metallic, semiconducting, and half-metallic. It is noted that the semiconducting state features a band gap of 0.07 eV. When spin-orbit coupling (SOC) is considered, valley polarization is exhibited in the Ni 2 Cl 3 I 3 /MoSe 2 heterostructure, with the degree of valley polarization varying across different configurations and reaching a maximum value of 4.6 meV. The electronic properties, valley polarization and MAE of the system can be tuned by biaxial strains. The application of a biaxial strain ranging from -6% to +6% can enhance the valley polarization value from 0.9 meV to 12.9 meV. The directions of MAE of the Ni 2 Cl 3 I 3 /MoSe 2 heterostructure can be changed at biaxial strains of -6%, +2%, +4% and +6%. The above calculation results show that the heterostructure system possesses rich electronic properties and tunability, with extensive potential applications in the fields of spintronic and valleytronic devices.

The hierarchical assembly of nanoapatite within a type I collagen matrix was achieved through biomimetic mineralization in vitro , cooperatively regulated by non-collagenous proteins and small biomolecules. Here, we demonstrated that IP6 could significantly promote intrafibrillar mineralization in two- and three-dimensional collagen models through binding to collagen fibrils via hydrogen bonds (the interaction energy ∼10.21 kJ mol -1 ), as confirmed by the FTIR spectra and isothermal experimental results. In addition, we find that IP6 associated with dental collagen fibrils can also enhance the remineralization of calcium-depleted dentin and restore its mechanical properties similar to the natural dentin within 4 days. The promoting effect is mainly due to the chemical modification of IP6, which alters the interfacial physicochemical properties of collagen fibrils, strengthening the interaction of calcium phosphate minerals and mineral ions with collagen fibrils. This strategy of interfacial regulation to accelerate the mineralization of collagen fibrils is essential for dental repair and the development of a clinical product for the remineralization of hard tissue.

Colloidal quantum dots (CQDs) have been a hot research topic ever since they were successfully fabricated in 1993 via the hot injection method. The Nobel Prize in Chemistry 2023 was awarded to Moungi G. Bawendi, Louis E. Brus and Alexei I. Ekimov for the discovery and synthesis of quantum dots. The Internet of Things (IoT) has also attracted a lot of attention due to the technological advancements and digitalisation of the world. This review first aims to give the basics behind QD physics. After that, the history behind CQD synthesis and the different methods used to synthesize most widely researched CQD materials (CdSe, PbS and InP) are revisited. A brief introduction to what IoT is and how it works is also mentioned. Then, the most widely researched CQD devices that can be used for the main IoT components are reviewed, where the history, physics, the figures of merit (FoMs) and the state-of-the-art are discussed. Finally, the challenges and different methods for integrating CQDs into IoT devices are discussed, mentioning the future possibilities that await CQDs.

With continuous advances in medical technology, non-invasive embolization has emerged as a minimally invasive treatment, offering new possibilities in cancer therapy. Fluorescent labeling can achieve visualization of therapeutic agents in vivo , providing technical support for precise treatment. This paper introduces a novel in situ non-invasive embolization composite material, Au NPs@( m PEG-PLGTs), created through the electrostatic combination of L-cysteine-modified gold nanoparticles (Au NPs) and methoxy polyethylene glycol amine-poly[(L-glutamic acid)-(L-tyrosine)] ( m PEG-PLGTs). Experiments were undertaken to confirm the biocompatibility, degradability, stability and performance of this tumor therapy. The research results demonstrated a reduction in tumor size as early as the fifth day after the initial injection, with a significant 90% shrinkage in tumor volume observed after a 20-day treatment cycle, successfully inhibiting tumor growth and exhibiting excellent anti-tumor effects. Utilizing near-infrared in vivo imaging, Au NPs@( m PEG-PLGTs) displayed effective fluorescence tracking within the bodies of nude BALB-c mice. This study provides a novel direction for the further development and innovation of in situ non-invasive embolization in the field, highlighting its potential for rapid, significant therapeutic effects with minimal invasiveness and enhanced safety.

The sluggish kinetics of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) significantly impede the broader implementation of Zn-air batteries (ZABs), underscoring the necessity for advanced high-efficiency materials to catalyze these electrochemical processes. Recent advancements have highlighted the potential of transition metal/carbon nanofiber (TM/CNF) composite materials, synthesized via electrospinning technology, due to their expansive surface area, profusion of active sites, and elevated catalytic efficacy. This review comprehensively examines the structural characteristics of TM/CNFs, with a particular emphasis on the pivotal role of electrospinning technology in fabricating diverse structural configurations. Additionally, it delves into the mechanistic underpinnings of various strategies aimed at augmenting the catalytic activity of TM/CNFs. A meticulous discourse is also presented on the application scope of TM/CNFs in the realm of electrocatalysis, with a special focus on their impact on the performance of assembled ZABs. Lastly, this review encapsulates the challenges and future prospects in the development of TM/CNF composite materials via electrospinning, aiming to provide an exhaustive understanding of the current state of research in this domain and to foster further advancements in the commercialization of ZABs.

The biomedical application of nanotechnology in cancer treatment has demonstrated significant potential for improving treatment efficiencies and ameliorating adverse effects. However, the medical translation of nanotechnology-based nanomedicines faces challenges including hazardous environmental effects, difficulties in large-scale production, and possible excessive costs. In the present study, we extracted and purified natural exosome-like nanoparticles (ELNs) from Phellinus linteus . These nanoparticles (denoted as P-ELNs) had an average particle size of 154.1 nm, displayed a negative zeta potential of -31.3 mV, and maintained stability in the gastrointestinal tract. Furthermore, P-ELNs were found to contain a diverse array of functional components, including lipids and pharmacologically active small-molecule constituents. In vitro investigations suggested that they exhibited high internalization efficiency in liver tumor cells (Hepa 1-6) and exerted significant anti-proliferative, anti-migratory, and anti-invasive effects against Hepa 1-6 cells. Strikingly, the therapeutic outcomes of oral P-ELNs were confirmed in an animal model of metastatic hepatocellular carcinoma by amplifying reactive oxygen species (ROS) and rebalancing the gut microbiome. These findings demonstrate the potential of P-ELNs as a promising oral therapeutic platform for liver cancer treatment.

Plasmonic nanostructures can be used to enhance the efficiency of upconversion nanoparticles (UCNPs) and enable new functionalities. However, the fabrication of these hybrid plasmon-UCNP nanostructures has traditionally relied on either wet chemistry or nanolithography routes that are difficult to control, scale up, or both. In this work, we present a scalable nanofabrication process, capable of producing a massive array of gold-UCNP hybrid nanostructures over a few mm 2 area and with excellent uniformity in the photoluminescence intensity. This new approach combines the scalability of the bottom-up self-assembly method and the precision of the top-down nanolithography approach. It provides an efficient alternative route for the production of plasmonically enhanced UCNPs. A detailed discussion on the optimization of the UCNP self-assembly, the gold nanodisk lithography, and the nanopattern transfer processes is presented here. Additionally, we showcase the potential of this new approach for fabricating mechanical force sensors based on the selective plasmonic enhancement of the UCNP emission. This new approach holds great potential in facilitating the production of plasmonically enhanced UCNPs that can be deployed for both imaging and sensing applications.

The electrothermal coupling model of Pt/CoFe 2 O 4 /TiO 2 /TiN devices was established to study their resistive switching characteristics and basic biological synaptic properties in our research. The processes of set and reset are simulated, and the distribution of the temperature, the electric field and the concentration of oxygen vacancies in the dielectric layer are obtained. The switching performance of the TiO 2 -based device is significantly improved after the CoFe 2 O 4 layer is inserted, with the switching voltage, working current and power consumption being reduced, while the switching ratio is increased. By changing the thermal conductivity of the top electrode, the rupture position of the conductive filament can be controlled. The I - V characteristics of the Pt/CoFe 2 O 4 /TiO 2 /TiN device during the reset and set processes are fitted linearly in logarithmic coordinates, and the ohmic conduction mechanism or the space-limited charge conduction mechanism is mainly satisfied in the high and low resistance states. Finally, the application of dual-layer devices on biological synapses is studied, and the basic biological characteristics of enhancement, inhibition and paired pulse promotion are simulated successfully. In addition, the redox reaction induced by oxygen vacancy migration also promotes the formation and rupture of the conductive filament. Results of the study show this ferrite material as an insertion layer in a resistive random-access memory structure that offers potential for future information storage and bioneuromorphic computation devices.

It is highly challenging to control (stop and resume as needed) molecular rotors because their intramolecular rotations are electronically enabled by delocalized σ bonding, and the desired control needs to be able to destroy and restore such σ bonding, which usually means difficult chemical manipulation (substitution or doping atom). In this work, we report CBe 4 H 6 , a molecular rotor that can be controlled independently of chemical manipulation. This molecule exhibited the uninterrupted free rotation of Be and H atoms around the central carbon in first-principles molecular dynamics simulations at high temperatures (600 and 1000 K), but the rotation cannot be witnessed in the simulation at room temperature (298 K). Specifically, when a C-H bond in the CBe 4 H 6 molecule adopts the equatorial configuration at 298 K, it destroys the central delocalized σ bonding and blocks the intramolecular rotation (the rotor is turned "OFF"); when it can adopt the axial configuration at 600 and 1000 K, the central delocalized σ bonding can be restored and the intramolecular rotation can be resumed (the rotor is turned "ON"). Neutral CBe 4 H 6 is thermodynamically favorable and electronically stable, as reflected by a wide HOMO-LUMO gap of 7.99 eV, a high vertical detachment energy of 9.79 eV, and a positive electron affinity of 0.24 eV, so it may be stable enough for the synthesis, not only in the gas phase, but also in the condensed phase.

Lead halide perovskites (LHPs) are emerging semiconductor materials for light-emitting diodes (LEDs) owing to their unique structure and superior optoelectronic properties. However, defects that initiate degradation of LHPs through external stimuli and prompt internal ion migration at the interfaces remain a significant challenge. The electric field (EF), which is a fundamental driving force in LED operation, complicates the role of these defects in the physical and chemical properties of LHPs. A deeper understanding of EF-induced defect behavior is crucial for optimizing the LED performance. In this review, the origins and characterization of defects are explored, indicating the influence of EF-induced defect dynamics on LED performance and stability. A comprehensive overview of recent defect passivation approaches for LHP bulk films and nanocrystals (NCs) is also provided. Given the ubiquity of EF, a summary of the EF-induced defect behavior can enhance the performance of perovskite LEDs and related optoelectronic devices.

Position-sensitive detectors (PSDs) based on the lateral photovoltaic effect are crucial components in non-contact distance measurement, process control, guidance systems, and other related applications. However, PSDs are challenging due to the narrow spectral range and low sensitivity, limiting further practical application. Here, we present an ultra-sensitive SnSe/Si PSD device. A large-area uniform SnSe nanorod (NR) array film was grown on Si using a glancing-angle magnetron sputtering deposition technique and a SnSe/Si heterojunction PSD device was fabricated. PSDs exhibit an excellent photoresponse in a wide spectral range of 405-980 nm, showing an ultrahigh position sensitivity of 1517.4 mV mm -1 and an excellent spectral sensitivity of 4 × 10 4 V W -1 . More importantly, the detection limit power of the device is as low as 10 nW, indicating the outstanding potential for weak light detection. Based on the unique structural features and interface effect, the mechanisms for the remarkable performance of the fabricated SnSe/Si PSD device are clarified. This work indicates the large potential of SnSe/Si heterojunctions as a promising material for ultrasensitive optical position-sensitive devices.

Circulating tumor cells in human peripheral blood play an important role in cancer metastasis. In addition to the size-based and antibody-based capture and separation of cancer cells, their electrical characterization is important for rare cell detection, which can prove fatal in point-of-care testing. Herein, an organic electrochemical transistor (OECT) biosensor made of solution-gated carboxyl graphene mixed with PEDOT:PSS for the detection of cancer cells in situ is reported. Carboxyl graphene was used in this work to modulate cancer cell morphology, which differs significantly from normal blood cells, to achieve rare cancer cell detection. When the concentration of carboxyl graphene mixed in PEDOT:PSS was increased from 0 to 5 mg mL -1 , the cancer cell surface area increased from 218 μm 2 to 530 μm 2 , respectively. A change in cell morphology was also detected by the OECT. Negative charges in the cancer cells induced a positive shift in gate voltage, which was approximately 40 mV for spherical-shaped cells. When the cell surface area increased, transfer curves of transistor revealed a negative shift in gate voltage. Therefore, the sensor can be used for in situ detection of cancer cell morphology during the cell capture process, which can be used to identify whether the captured cells are deformable.

Nanoparticle-functionalized carbon nanotubes are promising in many research fields, especially in sensing, due to their intriguing performance in catalysis. However, these nanomaterials are mainly produced through batch processes under harsh conditions, thus encountering inherent limitations of low throughput and uncontrollable morphology of functional nanoparticles (NPs). In this work, we propose a method for high-yield and continuous production of bimetallic (Pt-Pd) NPs on multi-walled carbon nanotubes (MWCNTs) at room temperature through a custom 3D-printed microfluidic platform. A homogenous particle nucleation and growth environment could be created on the microfluidic platform that was equipped with two 3D-printed micromixers. Pt-Pd NPs loaded on MWCNTs were prepared in the microfluidic platform with high throughput and controlled size, dispersity and composition. The synthetic parameters for these nanocomposites were investigated to optimize their electrocatalytic performance. The optimized nanocomposites exhibited excellent electrocatalytic activity with exceptional sensitivity and wide detection range, superior to their counterparts prepared via conventional approaches. This method proposed here could be further adapted for manufacturing other catalyst support materials, opening more avenues for future large-scale production and catalytic investigation of functional nanomaterials.

The utilization of metal nanoparticles for antibacterial thermoplastic composites has the potential to enhance the safety of human and animal life by mitigating the spread and transmission of foodborne pathogenic bacteria. The dispersion, antioxidant and antimicrobial activities of metal nanoparticles directly affect the application performance of the composites. This study focused on achieving amine-carboxyl co-modified copper nanoparticles (Cu-AC) with excellent antioxidant properties and monodispersity through in situ grafting of amine and carboxyl groups onto the surface of copper nanoparticles via ligand interaction. Polyacrylic acid's extended carbon chain structure was utilized to improve its dispersion and antioxidant properties, and its antibacterial properties were synergistically enhanced using secondary amines. It was found that Cu-AC possesses high antibacterial properties, with a minimum inhibition concentration of 0.156 mg mL -1 . Antibacterial masterbatches and their composites (polypropylene/Cu) manufactured by melt blending of polypropylene and Cu-AC exhibited excellent antibacterial rates of up to 90% and 99% at 300 ppm and 700 ppm Cu-AC, respectively. Additionally, Cu-AC bolstered the thermal degradation, processing and mechanical properties of polypropylene. The successful implementation of this product substantiates the potential applications of polypropylene/Cu composite materials across diverse industries.

This study uses hybrid functional calculations to investigate the effects of various crystal facet combinations in BiOCl and BiOI on the photocatalytic activity of the BiOCl/BiOI heterostructure. The results show that the separation efficiencies of photo-generated electron-hole pairs in BiOCl(010)/BiOI(001) and BiOCl(010)/BiOI(010) are constrained by type I band alignments in principle. In contrast, BiOCl(001)/BiOI(001) and BiOCl(001)/BiOI(010) heterostructures, which operate under the direct Z-scheme type, exhibit an enhanced photo-generated charge separation efficiency, superior redox capacity, and enhanced visible light absorption. Specifically, BiOCl(001)/BiOI(010) exhibits a more remarkable reduction ability that can reduce O 2 to ˙O 2 - . Furthermore, our investigations demonstrate that targeted I element doping in BiOCl(001)/BiOI(010) can reduce the band gap of the BiOCl(001) sheet, enhance visible light absorption, and maintain the direct Z-scheme characteristics, thereby further improving the photocatalytic performance. Additionally, we discovered that I doping can transform the BiOCl(010)/BiOI(001) heterostructure from type I into a direct Z-scheme heterostructure, resulting in a substantial enhancement in the separation efficiency and reduction ability of photo-generated carriers as well as visible light absorption with increasing I doping concentration. Considering the excellent charge injection efficiency observed in experiments with the BiOCl(010)/BiOI(001) heterostructure, I-BiOCl(010)/BiOI(001) may represent a superior photocatalyst. Thus, this study highlights the crucial and substantial roles of engineering specific crystal facet combinations and I doping in enhancing the photocatalytic performance of the BiOCl/BiOI heterostructure. This theoretical study contributes to the comprehension of related experimental findings and offers valuable insights for the development of novel BiOCl/BiOI heterostructures with superior photocatalytic activity.

Flash-sintered (FS) ceramics have shown promising mechanical deformability at room temperature compared to conventional sintered ceramics. One major contributing factor to plasticity is high-density defects, such as dislocations, stacking faults and point defects, resulted presumably from the high electrical field during flash sintering. However, such direct experiemtnal evidence for defect formation and evolution under the electric field remains lacking. Here we performed in situ biasing experiments in FS and conventionally sintered (CS) polycrystalline TiO 2 in a transmission electron microscope (TEM) to compare the defect evolution dynamics. In situ TEM studies revealed the coalescence of point defects under the electrical field in both FS and CS TiO 2 and the subsequent formation of stacking faults, which are often referred to as Wadsley defects. Surprisingly, under the electrical field, the average fault growth rate in the FS samples is 10 times as much as that in the CS TiO 2 . Furthermore, the Magnéli phase, a 3D oxygen-deficient phase formed by the aggregation of Wadsley defects, is observed in the FS samples, but not in the CS samples. The present study provides new insights into defect dynamics in FS ceramics.

Minimizing the amount of metallic lithium (Li) to zero excess to achieve an anode-free configuration can help achieve safer, higher energy density, and more economical Li metal batteries. Nevertheless, removal of excess Li creates challenges for long-term cycling performance in Li metal batteries due to the lithiophobic copper foils as anodic current collectors. Here, we improve the long-term cycling performance of anode-free Li metal batteries by modifying the anode-free configuration. Specifically, a lithiophilic Au nanoparticle-anchored reduced graphene oxide (Au/rGO) film is used as an anodic modifier to reduce the Li nucleation overpotential and inhibit dendrite growth by forming a lithiophilic Li x Au alloy and solid solution, which is convincingly evidenced by density functional theory calculations and experimentally. Meanwhile, the flexible rGO film can also act as a buffer layer to endure the volume expansion during repeated Li plating/stripping processes. In addition, the Au/rGO film promotes a homogeneous distribution of the electric field over the entire anodic surface, thus ensuring a uniform deposition of Li during the electrodeposition process, which is convincingly evidenced by finite element simulations. As expected, the Li||Au/rGO-Li half-cell shows a highly stable long-term cycling performance for at least 500 cycles at 0.5 mA cm -2 and 0.5 mA h cm -2 . A Li 2 S-based anode-free full cell allows achieving a stable operation life of up to 200 cycles with a capacity retention of 63.3%. This work provides a simple and scalable fabrication method to achieve anode-free Li 2 S-based cells with high anodic interface stability and a long lifetime.

Photocatalytic oxidation of toluene to valuable fine chemicals is of great significance, yet faces challenges in the development of advanced catalysts with both high activity and selectivity for the activation of inert C(sp 3 )-H bonds. Halide perovskites with remarkable optoelectronic properties have shown to be prospective photoactive materials, but the bulky structure with a small surface area and severe recombination of photogenerated electron-hole pairs are obstacles to application. Here, we fabricate a hierarchical nanoflower-shaped CsPbBr 3 /TiO 2 heterojunction by assembling CsPbBr 3 nanoparticles on 2D TiO 2 nanoflake subunits. The design significantly downsizes the size of CsPbBr 3 from micrometers to nanometers, and forms a type II heterojunction with intimate interfacial contact between CsPbBr 3 and TiO 2 nanoflakes, thereby accelerating the separation and transfer of photogenerated charges. Moreover, the formed hierarchical heterojunction increaseslight absorption by refraction and scattering, offers a large surface area and enhances the adsorption of toluene molecules. Consequently, the optimized CsPbBr 3 /TiO 2 exhibits a high performance (10 200 μmol g -1 h -1 ) for photocatalytic toluene oxidation with high selectivity (85%) for benzaldehyde generation under visible light. The photoactivity is about 20 times higher than that of blank CsPbBr 3 , and is among the best photocatalytic performances reported for selective oxidation of toluene under visible light irradiation.

Optical skyrmions have recently attracted growing interest due to their potential applications in deep-subwavelength imaging and nanometrology. While optical skyrmions have been successfully demonstrated using different field vectors, the study of their generation and control, as well as their general correlation with electromagnetic (EM) fields, is still in its infancy. Here, we theoretically propose that evanescent transverse-magnetic-polarized (TM-polarized) EM fields with rotational symmetry are actually Néel-type optical target skyrmions of the electric field vectors. Such optical target skyrmions are independent of the operation frequency and medium. Our proposal was verified by numerical simulations and real-space nano-imaging experiments performed on a graphene monolayer, where the target skyrmions could be as small as ∼100 nm in diameter. The results can therefore not only further our understanding of the formation mechanisms of EM topological textures, but also provide guidelines for the facile construction of EM skyrmions that may impact future information technologies.

The lack of macroscopic magnetic moments makes antiferromagnetic materials promising candidates for high-speed spintronic devices. The 2D ternary V-based chalcogenides (VXYSe 4 ; X, Y = Al, Ga) monolayers are investigated based on the density-functional theory and Monte Carlo simulations. The results reveal that the Néel temperature of the VGa 2 Se 4 monolayer is 18 K with zigzag2-antiferromagnetic (AFM) spin ordering. Also, the magnetic ordering of V ions in VAl 2 Se 4 and VAlGaSe 4 monolayers prefer zigzag1-AFM coupling with Néel temperature of 47 K and 33 K, respectively. The magnetic anisotropy calculations demonstrate that the easy magnetization axis of the VXYSe 4 monolayers is parallel to the y axis. In addition, the VXYSe 4 monolayers can be adjusted from the AFM state to the ferromagnetic (FM) state under biaxial stretching, which can be attributed to the competition between d-p-d superexchange and d-d direct exchange caused by the variation of bond length. The transition temperature of VXYSe 4 monolayers can be elevated above room temperature with the help of compression strain. In particular, the in-plane magnetic anisotropy is a robust characteristic regardless of the magnitude of the applied biaxial strain. These explorations not only enrich the family of AFM monolayers with excellent stability but also provide distinctive ideas for the performance control of AFM materials and their applications in nanodevices.

Monolayer (ML) Ga 2 O 3 with outstanding properties is promising for advanced nanodevice applications; however, its high exfoliation energy makes obtaining it challenging. In this study, we propose a more efficient solution to obtain ML Ga 2 O 3 by exfoliation from indium-doped bulk β-Ga 2 O 3 . The exfoliation efficiency with the assistance of In-doping and the doping influence on the stability and structural and electronic properties of ML Ga 2 O 3 are systematically studied using first-principles calculations. The exfoliation energy of ML Ga 2 O 3 is found to be reduced by 28% and is of the same order of magnitude as that of typical van der Waals (vdWs) 2D materials. Besides, excellent stability is preserved for ML Ga 2 O 3 at extremely high In doping concentration by phonon spectrum and ab initio molecular dynamics inspections. The bandgap of ML Ga 2 O 3 decreases from 4.88 to 4.25 eV with increased In concentration, and the modification of the VBM converts ML Ga 2 O 3 to a direct bandgap semiconductor. With the suppression of ZA mode phonon scattering, the pristine and In-doped ML Ga 2 O 3 exhibit high electron mobility, whereas the strong electron-phonon coupling (EPC) effect significantly decreases the hole mobility. Finally, the transfer characteristics of 5 nm MOSFETs based on the pristine and In-doped ML Ga 2 O 3 with varied In concentrations are simulated based on the non-equilibrium Green's function (NEGF) formalism. The I on for HP has a maximum of 3060 μA μm -1 at In doping concentration of 5% and is triple that of the pristine ML Ga 2 O 3 for LP at In doping concentration of 20%. The FOMs of n-type MOSFETs based on the In-doped ML Ga 2 O 3 and typical 2D materials are compared and shows huge potential for sub-5 nm applications. Our study applies a new strategy for obtaining ML Ga 2 O 3 and can also improve the device performance at the same time.

In clinical studies, the toxicity of platinum-based antitumor drugs limits their use. DNA is the most widely studied target of metal-based complexes. Thus, nuclear targeting and selective killing have become the purpose of ruthenium complex design. We synthesized a carboline derivative and its ruthenium complex, NBD and NBD-Ru, and characterized their properties. UV spectra were used to monitor their stability. Transmission electron microscopy and dynamic light scattering were used to identify the self-assembly properties. Inductively coupled plasma mass spectrometry was used to assay the distribution of the Ru complexes in cells with or without transferrin. Besides, the tumor cell killing activities with or without transferrin were detected by MTT assay. An imaging flow cytometer was applied to observe the fluorescence further to identify the cellular distribution. The effects of NBD and NBD-Ru on DNA and the cell cycle were also measured. In vivo , the antitumor and antimetastatic activities of NBD and NBD-Ru were assessed in S180 and LLC tumor-bearing mice. We found that introducing Ru improved the solubility and stability, enabling NBD-Ru to self-assemble into nanoparticles with the EPR effect. At the same time, binding affinity with transferrin increased significantly after complexation, meaning NBD-Ru could target and selectively kill tumors via Tf/TfR pathway. More interestingly, ruthenium assisted the complex in achieving nuclear penetration, which can kill tumor cells by interacting with DNA. In vivo experiments further verified our conclusion in vitro . NBD-Ru could inhibit not only the growth of a primary tumor but also lung metastasis, which was related to the killing effect of the complex on tumor cells (Ki67) and inhibition of neovascularization (CD31). At the same time, the systemic toxicity of the ruthenium complex in vivo was reduced because of the targeting effect, and the biosafety was improved. In conclusion, we found that ruthenium assisted in nuclear targeting and selective killing in vitro and in vivo .

Zinc oxide nanoparticles (ZnO NPs) have been actively pursued as the most effective electron transport layer for quantum-dot light-emitting diodes (QLEDs) in light of their unique optical and electronic properties and low-temperature processing. However, the high electron mobility and smooth energy level alignment at QDs/ZnO/cathode interfaces cause electron over-injection, which aggravates non-radiative Auger recombination. Meanwhile, the abundant defects hydroxyl group (-OH) and oxygen vacancies (O V ) in ZnO NPs act as trap states inducing exciton quenching, which synergistically reduces the effective radiation recombination for degrading the device performance. Here, we develop a bifunctional surface engineering strategy to synthesize ZnO NPs with low defect density and high environmental stability by using ethylenediaminetetraacetic acid dipotassium salt (EDTAK) as an additive. The additive effectively passivates surface defects in ZnO NPs and induces chemical doping simultaneously. Bifunctional engineering alleviates electron excess injection by elevating the conduction band level of ZnO to promote charge balance. As a result, state-of-the-art blue QLEDs with an EQE of 16.31% and a T 50 @100 cd m -2 of 1685 h are achieved, providing a novel and effective strategy to fabricate blue QLEDs with high efficiency and a long operating lifetime.

Optical limiters are greatly needed to protect eyes and sensitive optoelectronic devices such as photodetectors and sensors from laser damage, but they are currently plagued by low efficiency. In this work, we utilized Cu 3 VSe 4 nanocrystals (NCs) to enhance laser protection performance, and they exhibit higher saturation intensity and broader nonlinear spectral response extending into the near IR region than the C60 benchmark. A flexible optical limiter goggle prototype based on the NCs significantly attenuated the incident laser beam, with Z scan and I scan measurements demonstrating a giant nonlinear absorption coefficient β value of 1.0 × 10 -7 m W -1 , a large optical damage threshold of 3.5 J cm -2 , and a small starting threshold of 0.22 J cm -2 . Transient absorption spectroscopy disclosed that the origin of the excellent nonlinearity was associated with quasi-static dielectric resonance behavior and a large TPA cross-section of 3.3 × 10 6 GM was measured for Cu 3 VSe 4 NCs, suggesting the potential of intermediate bandgap (IB) semiconductors as alternatives to plasmonic noble metals for ultrafast photonics. Hence, optical limiters based on such semiconductors offer new avenues for laser protection in optoelectronic and defense fields.

Polydopamine (PDA) as an anode of potassium ion batteries (PIBs) has received a lot of attention due to its convenient preparation, environment friendliness, and low cost. However, due to the low conductivity of organic polydopamine, the active substance can easily dissolve in the cycle process, which leads to a low rate performance and short cycle life of PIBs. Here, dopamine was quantitatively polymerized onto the surface of a carbon-intertwined network of carbon nanotubes (CNTs). By means of density functional theory calculation and electrochemical measurement, the adsorption/desorption of potassium ions by oxygen-containing and nitro-containing functional groups in PDA and its promotion by CNTs are revealed. The π-π superposition effect between dopamine and CNTs effectively alleviates the dissolution of PDA during the cycle. A combination of PDA and CNTs could resolve low conductivity issues and provide excellent battery cycle performance. Results show that PDA@CNT-10 exhibits a high reversible capacity (223 mA h g -1 , 200 cycles at 0.2 A g -1 ) and a long cycle life (151 mA h g -1 , 3000 cycles at 1 A g -1 ). When first used as an organo-potassium hybrid capacitor assembled from the anode of the battery and activated carbon as the cathode, it can provide a high reversible capacity (76 mA h g -1 , 2000 cycles at 2 A g -1 ), which promotes the potential application of PIBs in the future.

Urea pollution is a growing environmental concern, and its removal via catalytic hydrolysis is challenging due to the resonance-stabilized amide bonds. In nature, this reaction is catalyzed by ureases in many soil bacteria. However, the remedy of this problem with natural enzymes is not feasible as they are easily denatured and require high costs for both preparation and storage. Given this, the development of nanomaterials bearing enzyme-like activity (nanozymes) with advantages such as low production cost, simple storage, and pH/thermal stability has attracted much attention over the past decade. As inspired by the mechanism of urease-catalyzed urea hydrolysis, the co-presence of Lewis acid (LA) and Brønsted acid (BA) sites is imperative to proceed with this reaction. Herein, layered HNb 3 O 8 samples with intrinsic BA sites were adopted for investigation. The layer reduction of this material to few-/single layers can expose Nb sites with various LA strengths depending on the degree of NbO 6 distortion. Among the catalysts examined, single-layer HNb 3 O 8 bearing strong LA and BA sites displays the best hydrolytic activity towards acetamide and urea. This sample with high thermal stability was found to outperform urease at temperatures higher than 50 °C. The acidity-activity correlation established in this study is believed to guide the future design of industrial catalysts to remediate urea pollution.

A combined computational and experimental study of small unilamellar vesicle (SUV) fusion on mixed self-assembled monolayers (SAMs) terminated with different deuterated tether moieties (-(CD 2 ) 7 CD 3 or -(CD 2 ) 15 CD 3 ) is reported. Tethered bilayer lipid membrane (tBLM) formation of synthetic 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine was initially probed on SAMs with controlled tether (d-alkyl tail) surface densities and lateral molecular packing using quartz crystal microbalance with dissipation monitoring (QCM-D). Long time-scale coarse-grained molecular dynamics (MD) simulations were then employed to elucidate the mechanisms behind the interaction between the SUVs and the different phases formed by the -(CD 2 ) 7 CD 3 and -(CD 2 ) 15 CD 3 tethers. Furthermore, a series of real time kinetics was recorded under different osmotic conditions using QCM-D to determine the accumulated lipid mass and for probing the fusion process. It is shown that the key factors driving the SUV fusion and tBLM formation on this type of surfaces involve tether insertion into the SUVs along with vesicle deformation. It is also evident that surface densities of the tethers as small as a few mol% are sufficient to obtain stable tBLMs with a high reproducibility. The described "sparsely tethered" tBLM system can be advantageous in studying different biophysical phenomena, such as membrane protein insertion, effects of receptor clustering, and raft formation.

Halide perovskites (HPs) are highly susceptible to heat, light, or moisture and are easily decomposed even in an ambient environment, which greatly hinders their practical applications. Herein, an in situ growth strategy is presented for implanting an inorganic lead-free HP, Cs 2 AgBiBr 6 , into SiO 2 sub-microcapsules to form a Cs 2 AgBiBr 6 @SiO 2 yolk-shell composite. The SiO 2 sub-microcapsule endows Cs 2 AgBiBr 6 with good thermal and light stability, as well as excellent corrosion resistance against polar solvents. Furthermore, when employed as a lead-free perovskite photocatalyst, the composite exhibits a higher visible-light-driven CO 2 -to-CO rate (271.76 μmol g -1 h -1 ) and much better stability than Cs 2 AgBiBr 6 in water. The formation of a Cs 2 AgBiBr 6 /SiO 2 heterostructure using an in situ growth method alleviates water binding on the perovskites, supported by density functional theory calculations, which is the key to an improvement in the stability of the composite. The in situ growth strategy developed here sheds light on the design and development of HP-based materials for applications involving polar solvents.

With the development of intelligent wearable electronic products, new requirements are put forward for large-scale production and durable power supplies and sensors. Herein, a flexible and stretchable single-electrode triboelectric nanogenerator (TENG) based on a medical conductive hydrogel (MCH) has been fabricated for biomechanical energy harvesting and electronic switches. The obtained MCH-TENG encapsulated by silicone rubber as an electrification layer demonstrated high electrical output performances. The size of the fabricated MCH-TENG was 40 × 60 mm 2 , which can generate an open-circuit voltage of 400 V, a power density of 444.44 mW m -2 , and power 240 LEDs in series at a contact frequency of 3.0 Hz. The device can act not only as a power supply to drive electronic devices, but also as an energy collector to collect the energy of human movements. Particularly, as an electronic switch, the device enabled a high current amplification through the Darlington transistor circuit. Consequently, this work provides a new perspective of flexible and stretchable MCH-TENGs for wearable electronic devices.

2 μm mid-infrared (MIR) light sources have shown great potential for broad applications in molecular spectroscopy, eye-safe lasers, biomedical systems and so on. However, previous research studies were mainly focused on conventional materials such as glasses, glass-ceramics and crystals, limiting the luminescence intensity and miniaturization of photonic devices. Here we report a new strategy to realize the multiple excitation wavelength responsive MIR emission in a single nanoparticle by employing an erbium sublattice as the sensitizing host. Intense 2 μm emission of Ho 3+ from its 5 I 7 → 5 I 8 optical transition was observed under 808, 980 and 1530 nm excitations. The possible energy transfer mechanism between Er 3+ and Ho 3+ ions was discussed. We also designed a core-shell-shell nanostructure by inserting an NaYF 4 :Yb interlayer to maximize the absorption of 980 nm photons and enhance the 2 μm emission. The MIR luminescence under 808 nm excitation can be further improved by introducing Nd 3+ into the outermost shell and attaching indocyanine green dyes. These results present an efficient way for the development of MIR luminescent nanomaterials with great potential in the fields of MIR gain devices, nanosized MIR light sources, and nanophotonics.

Carrier spatial separation efficiency and active electron density are the key factors affecting photocatalytic hydrogen evolution activity. Heterojunction catalysts with fast charge separation and directed electron transport systems were successfully prepared by a synergistic modification strategy of transition metal (Co) doping and crystal plane modulation. The optimized electronic structure and enhanced reaction kinetics enabled unidirectional electron transfer. Photocatalytic results show that CdS(002)/Co-C 3 N 4 exhibits remarkable hydrogen evolution activity (991.2 μmol h -1 g -1 ) in the absence of a co-catalyst, which is 37.0 and 3.4 times higher than that of C 3 N 4 (26.8 μmol h -1 g -1 ) and Co-C 3 N 4 (294.6 μmol h -1 g -1 ), respectively. Density functional theory (DFT) calculations indicate that the enhanced catalytic activity of CdS(002)/Co-C 3 N 4 is attributed to the reduced electron-hole recombination rate and the increased electron density at the active site. This work provides a new idea for the design of photocatalysts with directed charge transport channels from the perspective of re-optimizing heterojunctions.

Low-dimensional group IV-VI metal chalcogenide-based semiconductors hold great promise for opto-electronic device applications owing to their diverse crystalline phases and intriguing properties related to thermoelectric and ferroelectric effects. Herein, we demonstrate a universal chemical vapor deposition (CVD) growth method to synthesize stable germanium chalcogenide-based (GeS, GeS 2 , GeSe, GeSe 2 ) nanosheets, which increases the library of the p-type semiconductor. The phase transition between different crystalline polytypes can be deterministically controlled by hydrogen concentration in the reaction chamber. Structural characterization and synthesis experiments identify the behavior, where the higher hydrogen concentration promotes the transiton from germanium dichalcogenides to germanium monochalcogenides. The angle-polarized and temperature-dependent Raman spectra demonstrate the strong interlayer coupling and lattice orientation. Based on the optimized growth scheme and systematic comparison of electrical properties, GeSe nanosheet photodetectors were demonstrated, which exhibit superior device performance on SiO 2 /Si and HfO 2 /Si substrate with a high photoresponsivity up to 10 4 A W -1 , fast response time less than 15 ms, and high mobility of 3.2 cm 2 V -1 s -1 , which is comparable to the mechanically exfoliated crystals. Our results manifest the hydrogen-mediated deposition strategy as a facile control knob to engineer crystalline phases of germanium chalcogenides for high performance optoelectronic devices.

Polyanion-type phosphate materials with Na-super-ionic conductor structures are promising for next-generation sodium-ion battery cathodes, although the intrinsically low electroconductivity and limited energy density have restricted their practical applications. In this study, we put forward substituting an inert phosphate with a redox-active silicate to improve the energy density and intrinsic electroconductivity of polyanion-type phosphate materials, thus enabling an advance in sodium-ion battery cathodes. As a proof of concept, some of the phosphate of Na 3 V 2 (PO 4 ) 3 was replaced by silicate to fabricate Na 3 V 2 (PO 4 ) 2.9 (SiO 4 ) 0.1 , which exhibited a higher average discharge voltage of 3.36 V and a higher capacity of 115.8 mA h g -1 than pristine Na 3 V 2 (PO 4 ) 3 (3.31 V, 109.6 mA h g -1 ) at 0.5 C, therefore improving the energy density. Moreover, the introduced silicate enhanced the intrinsic electroconductivity of Na 3 V 2 (PO 4 ) 3 materials, as confirmed by both theoretical simulation and electrochemical measurements. After pairing with a commercial hard carbon anode, the optimized Na 3 V 2 (PO 4 ) 2.9 (SiO 4 ) 0.1 cathode enabled a stable-cycling full cell with 90.1% capacity retention after 300 cycles at 5 C and a remarkable average coulombic efficiency of 99.88%.

Noble metal nanoparticles are often used as cocatalysts to enhance the photocatalytic efficiency. While the effect of cocatalyst nanoparticle size and shape has widely been explored, the effect of the crystal phase is largely overlooked. In this work, we investigate the effect of Ru nanoparticle crystal phase, specifically regular hexagonal close-packed (hcp) and allotropic face-centered cubic (fcc) crystal phases, as cocatalyst decorated onto the surface of TiO 2 photocatalysts. As reference photocatalytic reaction the simultaneous photocatalytic production of benzaldehyde (BAD) and H 2 from benzyl alcohol was chosen. Both the fcc Ru/TiO 2 and hcp Ru/TiO 2 composites exhibit enhanced BAD and H 2 production rates compared to pristine TiO 2 due to the formation of a Schottky barrier promoting the photogenerated charge separation. Moreover, a 1.9-fold photoactivity enhancement of the fcc Ru/TiO 2 composite is achieved as compared to the hcp Ru/TiO 2 composite, which is attributed to the fact that the fcc Ru NPs are more efficient in facilitating the charge transfer as compared to hcp Ru NPs, thus inhibiting the recombination of electron-hole pairs and enhancing the overall photoactivity.

As a lab-on-soft biochip providing accurate and timely biomarker information, wearable biosensors can satisfy the increasing demand for intelligent e-health services, active disease diagnosis/therapy, and huge bioinformation data. As biomolecules generally could not directly produce detectable signals, biotransducers that specifically convert biomolecules to electrical or optical signals are involved, which determines the pivotal sensing performance including 3S (sensitivity, selectivity, and stability), reversibility, etc . The soft interface poses new requirements for biotransducers, especially equipment-free, facile operation, mechanical tolerance, and high sensing performance. In this review, we discussed the emerging electrochemical and optical biotransduction strategies on wearables from the aspects of the transduction mechanism, amplification strategies, biomaterial selection, and device fabrication procedures. Challenges and perspectives regarding future biotransducers for monitoring trace amounts of biomolecules with high fidelity, sensitivity, and multifunctionality are also discussed. It is expected that through fusion with functional electronics, wearable biosensors can provide possibilities to further decentralize the healthcare system and even build biomolecule-based intelligent cyber-physical systems and new modalities of cyborgs.