Superconducting Joining Concept for Internal Magnesium Diffusion-Processed Magnesium Diboride Wires

A superconducting joint of unreacted monofilament internal magnesium diffusion-processed magnesium diboride (MgB₂) wires was fabricated by exploiting the phenomenon of magnesium diffusion into the boron layer inside the superconducting joint. Unprecedentedly, the joint was able to carry an almost identical transport current compared to the bare wire in a 2-7 T magnetic field at 20 K. The joint also exhibited very low joint resistance of 2.01 × 10^-13 Ω in self-field at 20 K. Among commercially available superconductors, this work is the first to successfully realize a superconducting joint that is capable of transferring current from one conductor to another without any notable degradation under strong magnetic fields. This work demonstrates great potential to apply MgB₂ in a range of practical applications, where superconducting joints are essential.

Morphologically controlled cobalt oxide nanoparticles for efficient oxygen evolution reaction

Electrochemical water oxidation is one of the thrust areas of research today in solving energy and environmental issues. The morphological control in the synthesis of nanomaterials plays a crucial role in designing efficient electrocatalyst. In general, various synthetic parameters can direct the morphology of nanomaterials and often this is the main driving force for the electrocatalyst in tuning the rate of the oxygen evolution reaction (OER) for the electrochemical water-splitting. Here, a facile and cost-effective synthesis of spinel cobalt oxides (Co₃O₄) via a one-pot hydrothermal pathway with tunable morphology has been demonstrated. Different kinds of morphologies have been obtained by systematically varying the reaction time i.e. nanospheres, hexagon and nanocubes. Their catalytic activity has been explored towards OER in 1.0 M alkaline KOH solution. The catalyst Co₃O₄-24 h nanoparticles synthesized in 24 h reaction time shows the lowest overpotential (η) value of 296 mV at 10 mA cm^-2 current density, in comparison to that of other as-prepared catalysts i.e. Co₃O₄-pH9 (311 mV), Co₃O₄-12 h (337 mV), and Co₃O₄-6 h (342 mV) with reference to commercially available IrO₂ (415 mV). Moreover, Co₃O₄-24 h sample shows the outstanding electrochemical stability up to 25 h time.

Highly dispersed secondary building unit-stabilized binary metal center on a hierarchical porous carbon matrix for enhanced oxygen evolution reaction

Restricting the aggregation and rationally adjusting the electronic structure of binary metal centers in metal-organic framework (MOF) precursors are important for optimizing their performance as electrocatalysts for the oxygen evolution reaction (OER) and achieving low overpotential and high stability in such applications. Herein, we demonstrate the possibility of enhancing the electrochemical activity of MOF-derived binary metal center catalysts by controlling the form of the Fe species. The introduction of Fe-SBU (iron 2,5-dihydroxyterephthalic acid) into ZIF-67 is found to induce a distinct confinement effect and this can be exploited to improve the electroconductivity of binary metal center catalysts, and therefore, to reduce the OER reaction barrier (OOH* → O*). When applied as an OER catalyst in 1 M KOH solution, the Fe-SBU@Co-Matrix catalyst exhibits a low overpotential of 249 mV to reach a current density of 10 mA cm^-2 and high stability for over 40 h. This work describes the secondary growth treatment of MOF-derived porous carbons to promote their application as catalysts in energy conversion reactions.

Metal-incorporated mesoporous oxides: Synthesis and applications

Mesoporous oxides are outstanding metal nanoparticle catalyst supports owing to their well-defined porous structures. Such mesoporous architectures not only prevent the aggregation of metal nanoparticles but also enhance their catalytic performance. Metal/metal oxide heterojunctions exhibit unique chemical and physical properties because of the surface reconstruction around the junction and electron transfer/interaction across the interface. This article reviews the methods used for synthesizing metal-supported hybrid nanostructures and their applications as catalysts for environmental remediation and sensors for detecting hazardous materials.

Free-standing membranes from the chemical exfoliation of mesoporous amorphous titania thin film

Thin films are typically bound to their substrate, limiting their integration on rough, porous, curved or chemically/thermally sensitive surfaces. Instead of employing tedious and expensive back-etching processes, specific chemical routes can enable the exfoliation of such thin structures. Herein, we demonstrate that an alkaline treatment can exfoliate a hybrid thin film comprising amorphous titania embedded in well-ordered block-copolymer micelles, which can be redeposited elsewhere. We provide sufficient evidence of the preservation of pore ordering and the importance of neutralizing the solution to spare the system from the redissolution of the titania species.

Significant role of thorny surface morphology of polyaniline on adsorption of triiodide ions towards counter electrode in dye-sensitized solar cells

Revealing the adsorption behavior of polyaniline with thorny surface morphology towards triiodide ions and its impact on the dye-sensitized solar cell performance.

Hollow Carbon-Based Nanoarchitectures Based on ZIF: Inward/Outward Contraction Mechanism and Beyond

Hollow carbon-based nanoarchitectures (HCAs) derived from zeolitic imidazolate frameworks (ZIFs), by virtue of their controllable morphology and dimension, high specific surface area and nitrogen content, richness of metal/metal compounds active sites, and hierarchical pore structure and easy exposure of active sites, have attracted great interests in many fields of applications, especially in heterogeneous catalysis, and electrochemical energy storage and conversion. Despite various approaches that have been developed to prepare ZIF-derived HCAs, the hollowing mechanism has not been clearly disclosed. Herein, a specialized overview of the recent progress of ZIF-derived HCAs is introduced to provide an insight into their preparation strategy and the corresponding hollowing mechanisms. Based on the fundamental understanding of the structural evolution of ZIF nanocrystals during the high-temperature pyrolysis process, the hollowing mechanisms of ZIF-derived HCAs are classified into four categories: i) inward contraction of core-shell template@ZIF composites or hollow ZIFs, ii) outward contraction of ZIF@shell composites, iii) special outward contraction of ZIF arrays, and iv) mechanism beyond inward/outward contraction of pure ZIF nanocrystals. Finally, an outlook on the development prospects and challenges of HCAs based on ZIF precursors, especially in terms of controlled synthesis and future electrochemical application, is further discussed.

Long-Term Electrodeposition under a Uniform Parallel Magnetic Field. 1. Instability of Two-Dimensional Nucleation in an Electric Double Layer

Under a parallel magnetic field, after long-term copper deposition from an acidic copper sulfate solution, numerous spherical secondary nodules of 10 to 100 μm diameters were formed one upon another in dendritic mode. This is a new type of micro-magnetohydrodynamic (MHD) effect arising from the unstable growth of three-dimensional (3D) and two-dimensional (2D) nuclei by specific adsorption of hydrogen ions (second micro-MHD effect). From the viewpoint of instability in electrodeposition, though 3D nucleation in the diffusion layer is always unstable, with ionic specific adsorption such as hydrogen ions, stable 2D nucleation turns unstable after long-term deposition. The resultant competitive growth of 3D and 2D nuclei produces spherical nodules as their composite, leading to their dendritic growth. Furthermore, though negligibly small, nonequilibrium fluctuations occurring in 2D nucleation migrate with the laminar solution flow caused by Lorentz force (MHD flow). Depending on whether the ionic adsorption is specific or nonspecific, the traveling asymmetrical fluctuation changes the direction to the upstream or downstream side, respectively.

Long-Term Electrodeposition under a Uniform Parallel Magnetic Field. 2. Flow-Mode Transition from Laminar MHD Flow to Convection Cells with Two-Dimensional (2D) Nucleation

Following the analysis of the self-organization of two-dimensional (2D) nuclei in Part 1, the flow-mode transition from laminar magnetohydrodynamics (MHD) flow to convection cells accompanied by 2D nucleation under a uniform parallel magnetic field was theoretically examined using the statistical mechanics of nonequilibrium fluctuation. As a result, it was clarified that secondary nodules of 2D nuclei develop with multiple nucleations during the transition, forming a one-upon-another structure. Then, the evolution of the convection cells as well as the secondary nodules requires unstable growth of the asymmetrical fluctuations by the specific adsorption of an ion. As predicted by the theory, the electrolytic current in copper deposition with specific adsorption of hydrogen ions under a parallel magnetic field developed with time, resulting in a nonlinear steplike curve in a 1200 s deposition time.

Amorphous Alloy Architectures in Pore Walls: Mesoporous Amorphous NiCoB Alloy Spheres with Controlled Compositions via a Chemical Reduction

Amorphous bimetallic borides are an emerging class of catalytic nanomaterial that has demonstrated excellent catalytic performance due to its glass-like structure, abundant unsaturated active sites, and synergistic electronic effects. However, the creation of mesoporous Earth-abundant bimetallic metal borides with tunable metal proportion remains a challenge. Herein, we develop a sophisticated and controllable dual-reducing agent strategy to synthesize the mesoporous nickel-cobalt boron (NiCoB) amorphous alloy spheres (AASs) with adjustable compositions by using a soft template-directed assembly approach. The selective use of tetrabutylphosphonium bromide (Bu₄PBr) is beneficial to generate well-defined mesopores because it both moderates the reduction rate by decreasing the reducibility of M²⁺ species and prevents the generation of soap bubbles. Our meso-Ni_10.0Co_74.5B_15.5 AASs generate the highest catalytic performance for the hydrolytic dehydrogenation of ammonia borane (AB). Its high performance is attributed to the combination of optimal synergistic effects between Ni, Co, and B as well as the high surface area and the good mass transport efficiency due to the open mesopores. This work describes a systematic approach for the design and synthesis of mesoporous bimetallic borides as efficient catalysts.

Tunable Concave Surface Features of Mesoporous Palladium Nanocrystals Prepared from Supramolecular Micellar Templates

Concave metallic nanocrystals with a high density of low-coordinated atoms on the surface are essential for the realization of unique catalytic properties. Herein, mesoporous palladium nanocrystals (MPNs) that possess various degrees of curvature are successfully synthesized following an approach that relies on a facile polymeric micelle assembly approach. The as-prepared MPNs exhibit larger surface areas compared to conventional Pd nanocrystals and their nonporous counterparts. The MPNs display enhanced electrocatalytic activity for ethanol oxidation when compared to state-of-the-art commercial palladium black and conventional palladium nanocubes used as catalysts. Interestingly, as the degree of curvature increases, the surface-area-normalized activity also increases, demonstrating that the curvature of MPNs and the presence of high-index facets are crucial considerations for the design of electrocatalysts.

Mesoporous Nanoarchitectures for Electrochemical Energy Conversion and Storage

Mesoporous materials have attracted considerable attention because of their distinctive properties, including high surface areas, large pore sizes, tunable pore structures, controllable chemical compositions, and abundant forms of composite materials. During the last decade, there has been increasing research interest in constructing advanced mesoporous nanomaterials possessing short and open channels with efficient mass diffusion capability and rich accessible active sites for electrochemical energy conversion and storage. Here, the synthesis, structures, and energy-related applications of mesoporous nanomaterials are the main focus. After a brief summary of synthetic methods of mesoporous nanostructures, the delicate design and construction of mesoporous nanomaterials are described in detail through precise tailoring of the particle sizes, pore sizes, and nanostructures. Afterward, their applications as electrode materials for lithium-ion batteries, supercapacitors, water-splitting electrolyzers, and fuel cells are discussed. Finally, the possible development directions and challenges of mesoporous nanomaterials for electrochemical energy conversion and storage are proposed.

Nanoarchitectonics for Wide Bandgap Semiconductor Nanowires: Toward the Next Generation of Nanoelectromechanical Systems for Environmental Monitoring

Semiconductor nanowires are widely considered as the building blocks that revolutionized many areas of nanosciences and nanotechnologies. The unique features in nanowires, including high electron transport, excellent mechanical robustness, large surface area, and capability to engineer their intrinsic properties, enable new classes of nanoelectromechanical systems (NEMS). Wide bandgap (WBG) semiconductors in the form of nanowires are a hot spot of research owing to the tremendous possibilities in NEMS, particularly for environmental monitoring and energy harvesting. This article presents a comprehensive overview of the recent progress on the growth, properties and applications of silicon carbide (SiC), group III-nitrides, and diamond nanowires as the materials of choice for NEMS. It begins with a snapshot on material developments and fabrication technologies, covering both bottom-up and top-down approaches. A discussion on the mechanical, electrical, optical, and thermal properties is provided detailing the fundamental physics of WBG nanowires along with their potential for NEMS. A series of sensing and electronic devices particularly for environmental monitoring is reviewed, which further extend the capability in industrial applications. The article concludes with the merits and shortcomings of environmental monitoring applications based on these classes of nanowires, providing a roadmap for future development in this fast-emerging research field.

Effect of N2 flow rate on kinetic investigation of lignin pyrolysis

Fast pyrolysis of lignin can obtain valuable products such as bio-oil, bio-chemical, syngas, and biochar. In this study, two types of lignin known as brown solid from the byproduct of cellulosic ethanol fermentation and commercial dealkaline lignin from the papermaking process were used for pyrolysis in a 3-L batch reactor at 300-450 °C. The product composition in the liquid and gas phases were analyzed by using gas chromatography-mass spectrometry/Flame-ionization detector/thermal conductivity detector (GC-MS/FID/TCD). Increasing the N₂ flow rate to 150 mL/min was sufficient to increase the production of bio-oil/bio-organics up to 15% for brown solid pyrolysis. In contrast, the biochemical production during dealkaline lignin pyrolysis was not sensitive to the change of the N₂ flow rate. The amount of biochar produced in the pyrolysis (~60%) slightly changed at various pyrolysis temperature and gas flow rate, which could be due to the relatively low pyrolysis temperature that was insufficient to decompose the lignin. The GC-MS analysis also revealed that C7-C8 compounds, which represented the phenolic compounds, were the most abundant in the liquid products. Kinetic models of the pyrolysis were established based on the thermogravimetric analysis.

Pseudocapacitive Lithium Storage of Cauliflower-Like CoFe2 O4 for Low-Temperature Battery Operation

Binary transition-metal oxides (BTMOs) with hierarchical micro-nano-structures have attracted great interest as potential anode materials for lithium-ion batteries (LIBs). Herein, we report the fabrication of hierarchical cauliflower-like CoFe₂ O₄ (cl-CoFe₂ O₄ ) via a facile room-temperature co-precipitation method followed by post-synthetic annealing. The obtained cauliflower structure is constructed by the assembly of microrods, which themselves are composed of small nanoparticles. Such hierarchical micro-nano-structure can promote fast ion transport and stable electrode-electrolyte interfaces. As a result, the cl-CoFe₂ O₄ can deliver a high specific capacity (1019.9 mAh g^-1 at 0.1 A g^-1 ), excellent rate capability (626.0 mAh g^-1 at 5 A g^-1 ), and good cyclability (675.4 mAh g^-1 at 4 A g^-1 for over 400 cycles) as an anode material for LIBs. Even at low temperatures of 0 °C and -25 °C, the cl-CoFe₂ O₄ anode can deliver high capacities of 907.5 and 664.5 mAh g^-1 at 100 mA g^-1 , respectively, indicating its wide operating temperature. More importantly, the full-cell assembled with a commercial LiFePO₄ cathode exhibits a high rate performance (214.2 mAh g^-1 at 5000 mA g^-1 ) and an impressive cycling performance (612.7 mAh g^-1 over 140 cycles at 300 mA g^-1 ) in the voltage range of 0.5-3.6 V. Kinetic analysis reveals that the electrochemical performance of cl-CoFe₂ O₄ is dominated by pseudocapacitive behavior, leading to fast Li⁺ insertion/extraction and good cycling life.

Clinical features of elderly-onset Adult-onset Still's disease

OBJECTIVES

To clarify the characteristics of patients with elderly-onset Adult-onset Still's disease (AOSD).

METHODS

Patients were classified into elderly-onset (>60 years: 47 patients) and younger-onset (≤60 years: 95 patients) groups according to their age at diagnosis of AOSD. Clinical features, treatments, and prognosis were compared between the elderly-onset and younger-onset groups.

RESULTS

In the elderly-onset group, compared with the younger-onset group, typical skin rashes were less frequent (21.3% vs 58.9%, respectively; p < .0001), whereas pleuritis (27.7% vs 7.4%, respectively; p = .0011) and disseminated intravascular coagulation (19.1% vs 2.1%, respectively; p = .0004) were more frequent, and serum ferritin levels were higher (median 12,700 ng/ml vs 2526 ng/ml, respectively; p < .0001). Overall survival and AOSD-related survival were reduced (p = .0006 and p = .0023, respectively) and drug-free remission was less frequent (p = .0035) in the elderly-onset group compared with the younger-onset group.

CONCLUSIONS

Our results demonstrated that elderly-onset AOSD patients had several characteristics that differed from younger-onset AOSD patients, including less typical skin lesions, more AOSD-related complications, higher ferritin levels, and poorer prognoses.

Electrochemical Synthesis of Mesoporous Architectured Ru Films Using Supramolecular Templates

The electrochemical synthesis of mesoporous ruthenium (Ru) films using sacrificial self-assembled block polymer micelles templates, and its electrochemical surface oxidation to RuO_x is described. Unlike standard methods such as thermal oxidation, the electrochemical oxidation method described here retains the mesoporous structure. Ru oxide materials serve as high-performance supercapacitor electrodes due to their excellent pseudocapacitive behavior. The mesoporous architectured film shows superior specific capacitance (467 F g^-1_Ru ) versus a nonporous Ru/RuO_x electrode (28 F g^-1_Ru ) that is prepared via the same method but omitting the pore-directing polymer. Ultrahigh surface area materials will play an essential role in increasing the capacitance of this class of energy storage devices because the pseudocapacitive redox reaction occurs on the surface of electrodes.

General Formation of Macro-/Mesoporous Nanoshells from Interfacial Assembly of Irregular Mesostructured Nanounits

Mesoporous core-shell nanostructures with controllable ultra-large open channels in their nanoshells are of great interest. However, soft template-directed cooperative assembly to mesoporous nanoshells with highly accessible pores larger than 30 nm, or even above 50 nm into macroporous range, remains a significant challenge. Herein we report a general approach for precisely tailored coating of hierarchically macro-/mesoporous polymer and carbon shells, possessing highly accessible radial channels with extremely wide pore size distribution from ca. 10 nm to ca. 200 nm, on diverse functional materials. This strategy creates opportunities to tailor the interfacial assembly of irregular mesostructured nanounits on core materials and generate various core-shell nanomaterials with controllable pore architectures. The obtained Fe,N-doped macro-/mesoporous carbon nanoshells show enhanced electrochemical performance for the oxygen reduction reaction in alkaline condition.

Highly ordered macroporous dual-element-doped carbon from metal-organic frameworks for catalyzing oxygen reduction

Multiple heteroatom-doped carbons with 3D ordered macro/meso-microporous structures have not been realized by simple carbonization of metal-organic frameworks (MOFs). Herein, ordered macroporous phosphorus- and nitrogen-doped carbon (M-PNC) is prepared successfully by carbonization of double-solvent-induced MOF/polystyrene sphere (PS) precursors accompanied with spontaneous removal of the PS template, followed by post-doping. M-PNC shows a high specific surface area of 837 m2 g-1, nitrogen doping of 3.17 at%, and phosphorus doping of 1.12 at%. Thanks to the hierarchical structure, high specific surface area, and multiple heteroatom-doping, M-PNC exhibits unusual catalytic activity as an electrocatalyst for the oxygen reduction reaction. Computational calculation reveals that the P[double bond, length as m-dash]O group helps stabilize the adsorption of intermediates, and the position of P[double bond, length as m-dash]O relative to graphitic N significantly improves the activity of the adjacent carbons for electrocatalysis.

Assembling well-arranged covalent organic frameworks on MOF-derived graphitic carbon for remarkable formaldehyde sensing

Constructing heterostructures with advanced architectures is an effective strategy for enhancing the crystallinity and functional performance of covalent organic frameworks (COFs). Herein, a novel core-shell heterostructure integrating a metal-organic framework (MOF)-derived graphitic carbon core (GC) and a well-arranged COF shell, termed MOF-GC@COF, is reported. ZIF-67 dodecahedra are first chemically etched with a weak organic acid and further converted to MOF-GC via thermal pyrolysis. In the subsequent step, β-ketoenamine-linked COF nanofibers are vertically assembled on the surface of the MOF-GC cores to generate the MOF-GC@COF heterostructure. As a proof-of-concept application, the as-prepared MOF-GC@COF heterostructure is used as an effective quartz crystal microbalance (QCM) sensor for the adsorption of formaldehyde. Benefiting from the synergistic effect of the hybrid composition and the advantages of the core-shell heterostructure, the newly prepared MOF-GC@COF heterostructure exhibits excellent sensing performance toward formaldehyde with rapid adsorption kinetics, high sensitivity, and superior selectivity.

Photodegradation Activity of Poly(ethylene oxide-b-ε-caprolactone)-Templated Mesoporous TiO₂ Coated with Au and Pt

Mesoporous TiO₂ films are synthesized through evaporation-induced self-assembly using poly(ethylene oxide-b-ε-caprolactone) diblock copolymers as a soft-template. Using small-angle X-ray scattering and scanning electron microscopy, we investigate the effect of the TiO₂/PEO-b-PCL ratio on the resulting nanoarchitectonic structure. After sputter-coating Au and Pt layers, these Au/TiO₂ and Pt/TiO₂ nanocomposite films display drastically enhanced photodegradation of rhodamine 6G under ultraviolet irradiation, due to the metal films inhibiting the rapid recombination of photogenerated charge carriers.

Tailored Nanoarchitecturing of Microporous ZIF-8 to Hierarchically Porous Double-Shell Carbons and Their Intrinsic Electrochemical Property

Mesostructured polydopamine (PDA) coating has been successfully achieved on the surface of zeolitic imidazolate framework-8 (ZIF-8) particles by incorporating Pluronic F127 (with a pore-expanding agent, 1,3,5-trimethylbenzene) as a pore-directing agent during dopamine polymerization. Upon pyrolysis at high temperatures, mesostructured PDA-coated ZIF-8 particles become hierarchically porous double-shell carbons (HPDCs) with a wide pore size distribution ranging from micro- and meso- to macropores. The formation of a hollow inner shell progresses initially with the shrinkage of ZIF-8 at the periphery where the interface interactions with mesostructured PDA exist, and then the subsequent disintegration of the ZIF-8 core at higher temperatures occurs. Our HPDCs prepared in this study feature physical and electrochemical advantages of hierarchically porous carbons such as high electrochemically accessible surface area, short diffusion distance, and high mass-transfer rate, thus demonstrating significantly improved ion diffusion and surface-enhanced high specific capacitance at high charge-discharge rates. HPDC_5.0 therefore exhibits the capacitance retention of up to 76.7% from 1 to 10 A g^-1 and maximum specific capacitance of 344.7 F g^-1 at 1 mV s^-1. It also possesses superior electrochemical stability with about 108% capacitance retention even after 10,000 consecutive cycles of galvanostatic charge-discharge at 10 A g^-1.

Non-precious molybdenum nanospheres as a novel cocatalyst for full-spectrum-driven photocatalytic CO2 reforming to CH4

Photocatalytic CO₂ reforming is considered to be an effective method for clean, low-cost, and environmentally friendly reduction and conversion of CO₂ into hydrocarbon fuels by utilizing solar energy. However, the low separation efficiency of charge carriers and deficient reactive sites have severely hampered the efficiency of the photocatalytic CO₂ reforming process. Therefore, cocatalysts are usually loaded onto the surface of semiconductor photocatalysts to reduce the recombination of charge carriers and accelerate the rates of surface reactions. Herein, molybdenum (Mo) nanospheres are proposed as a novel non-precious cocatalyst to enhance the photocatalytic CO₂ reforming of g-C₃N₄ significantly. The Mo nanospheres boost the adsorption of CO₂ and activate the surface CO₂via a photothermal effect. The time-resolved fluorescence decay spectra reveals that the lifetime of photo-induced charge carriers is prolonged by the Mo nanospheres, which guarantees the migration of charge carriers from g-C₃N₄ to Mo nanospheres. Unexpectedly, Mo loaded g-C₃N₄ can effectively utilize a wide spectral range from UV to near-infrared region (NIR, up to 800 nm). These findings highlight the potential of Mo nanospheres as a novel cocatalyst for photocatalytic CO₂ reforming to CH₄.

Cancer biomarker profiling using nanozyme containing iron oxide loaded with gold particles

Nanozymes are nanomaterials with intrinsic magnetism and superparamagnetic properties. In the presence of an external magnet, nanozyme particles aggregate and redisperse without a foreign attraction. We evaluated the performances of nanozyme by changing the biosensing platforms and substituting other biological variants for a complete cancer assay detection. We investigated the expression of morphological variants in the transmission of signals using an electrochemical method. The signal responses, including signal enhancement with the nanozyme (Au-Fe₂O₃), showed a wide capturing range (greater than 80%, from 10² to 10⁵ cells ml^-1 in phosphate-buffered saline buffer, pH 7.4). The platform showed a fast response time within a dynamic range of 10-10⁵ cells ml^-1 for the investigated T47D cancer cell line. We also obtained higher responses for anti-HER2 (human epidermal receptor 2)/streptavidin interface as the biosensing electrode in the presence of T47D cancer cells. The positive assay produced a sixfold increase in current output compared to the negative target or negative biological variant. We calculated the limit of detection at 0.4 U ml^-1, and of quantitation at 4 U ml^-1 (units per millilitre). However, blood volume amounts in clinical settings may constrain diagnosis and increase detection limit value significantly.

Significant Improvement in Electrical Conductivity and Figure of Merit of Nanoarchitectured Porous SrTiO3 by La Doping Optimization

SrTiO₃ is a well-studied n-type metal oxide based thermoelectric (TE) material. In this work, the first-principles calculation of La-doped SrTiO₃ has been performed using the density functional theory. In addition, high TE properties of bulk SrTiO₃ material have been achieved by introducing nanoscale porosity and optimizing carrier concentration by La doping. The X-ray diffraction, atomic resolution scanning transmission electron microscopy imaging, and energy-dispersive X-ray spectrometry results show that La has been doped successfully into the lattice. The scanning electron microscopy images confirm that all the samples have nearly similar nanoscale porosities. The significant enhancement of electrical conductivity over the broad temperature range has been observed through optimization of La doping. Additionally, the samples possess very low thermal conductivity, which is speculated because of the nanoscale porosity of the samples. Because of this dual mechanism of doping optimization and nanoscale porosity, there is a remarkable improvement in power factor, 1 mW/m²K from 650 to 800 K, and figure of merit, zT of 0.26 at 850 K, of the sample, 22 at. % La-doped SrTiO₃.

Layer-by-Layer Motif Heteroarchitecturing of N,S-Codoped Reduced Graphene Oxide-Wrapped Ni/NiS Nanoparticles for the Electrochemical Oxidation of Water

A new heterostructured material is synthesized with lamellar arrangements in nanoscale precision through an innovative synthetic approach. The self-assembled Ni-based cyano-bridged coordination polymer flakes (Ni-CP) and graphene oxide (GO) nanosheets with a layered morphology (Ni-CP/GO) are used as precursors for the synthesis of multicomponent hybrid materials. Annealing of Ni-CP/GO in nitrogen at 450 °C allows the formation of Ni₃ C/rGO nanocomposites. Grinding Ni-CP/GO and thiourea and annealing under the same conditions produces N,S-codoped reduced GO-wrapped NiS₂ flakes (NiS₂ /NS-rGO). Interestingly, further heating up to 550 °C allows the phase transformation of NiS₂ into NiS accompanied by the formation of a face-centered cubic (FCC-Ni) metal phase between NS-rGO layers (FCC-Ni-NiS/NS-rGO). Among all the materials, the resulting FCC-Ni-NiS/NS-rGO exhibits good electrocatalytic activity and stability toward the oxygen evolution reaction (OER) owing to the synergistic effect of multiphases, the well-designed alternating layered structures on the nanoscale with abundant active sites.

In-situ fabrication of nanoarchitectured MOF filter for water purification

Sulfate radical (SO₄^•-)-based advanced oxidation processes (SR-AOPs) hold great promise for water purification due to their strong oxidizing and high selectivity. Recently, metal-organic frameworks (MOFs) as catalysts for peroxymonosulfate (PMS) activation to generate SO₄^•- have shown a bright future. However, the intrinsic nature of powder MOF nanocrystals, such as brittleness and poor processability, largely disturb their large-scale applications in practical. Herein, we develop an in situ growth method to prepare MOF filters. ZIF-67 in situ growth on the polyacrylonitrile (PAN) fibers lead to the ZIF-67/PAN composite fibers with high loading (up to 50 wt %). The loading ZIF-67 can retain their morphology and structure, which is comparable with that of pristine ZIF-67 powder. The ZIF-67/PAN filter demonstrates a high efficiency for organic pollutants removal by PMS activation. Furthermore, through the fabrication of filtration device, the dynamic catalysis results show the ZIF-67/PAN filter is a promising material for water purification. This work provides a new method for applying MOFs-based functional materials to practical water remediation and other separation applications.

Nanoarchitectured Structure and Surface Biofunctionality of Mesoporous Silica Nanoparticles

Mesoporous silica nanoparticles (MSNs), one of the important porous materials, have garnered interest owing to their highly attractive physicochemical features and advantageous morphological attributes. They are of particular importance for use in diverse fields including, but not limited to, adsorption, catalysis, and medicine. Despite their intrinsic stable siliceous frameworks, excellent mechanical strength, and optimal morphological attributes, pristine MSNs suffer from poor drug loading efficiency, as well as compatibility and degradability issues for therapeutic, diagnostic, and tissue engineering purposes. Collectively, the desirable and beneficial properties of MSNs have been harnessed by modifying the surface of the siliceous frameworks through incorporating supramolecular assemblies and various metal species, and through incorporating supramolecular assemblies and various metal species and their conjugates. Substantial advancements of these innovative colloidal inorganic nanocontainers drive researchers in promoting them toward innovative applications like stimuli (light/ultrasound/magnetic)-responsive delivery-associated therapies with exceptional performance in vivo. Here, a brief overview of the fabrication of siliceous frameworks, along with discussions on the significant advances in engineering of MSNs, is provided. The scope of the advancement in terms of structural and physicochemical attributes and their effects on biomedical applications with a particular focus on recent studies is emphasized. Finally, interesting perspectives are recapitulated, along with the scope toward clinical translation.

Layered transition metal dichalcogenide/carbon nanocomposites for electrochemical energy storage and conversion applications

Layered transition metal dichalcogenide (LTMD)/carbon nanocomposites obtained by incorporating conductive carbons such as graphene, carbon nanotubes (CNT), carbon nanofibers (CF), hybrid carbons, hollow carbons, and porous carbons exhibit superior electrochemical properties for energy storage and conversion. Due to the incorporation of carbon into composites, the LTMD/carbon nanocomposites have the following advantages: (1) highly efficient ion/electron transport properties that promote electrochemical performance; (2) suppressed agglomeration and restacking of active materials that improve the cycling performance and electrocatalytic stability; and (3) unique structures such as network, hollow, porous, and vertically aligned nanocomposites that facilitate the shortening of the ion and electrolyte diffusion pathway. In this context, this review introduces and summarizes the recent advances in LTMD/carbon nanocomposites for electrochemical energy-related applications. First, we briefly summarize the reported synthesis strategies for the preparation of LTMD/carbon nanocomposites with various carbon materials. Following this, previous studies using rationally synthesized nanocomposites are discussed based on a variety of applications related to electrochemical energy storage and conversion including Li/Na-ion batteries (LIBs/SIBs), Li-S batteries, supercapacitors, and the hydrogen evolution reaction (HER). In particular, the sections on LIBs and the HER as representative applications of LTMD/carbon nanocomposites are described in detail by classifying them with different carbon materials containing graphene, carbon nanotubes, carbon nanofibers, hybrid carbons, hollow carbons, and porous carbons. In addition, we suggest a new material design of LTMD/carbon nanocomposites based on theoretical calculations. At the end of this review, we provide an outlook on the challenges and future developments in LTMD/carbon nanocomposite research.

Highly Reversible and Rapid Sodium Storage in GeP3 with Synergistic Effect from Outside-In Optimization

The composite GeP₃/C@rGO as a sodium ion battery anode material was fabricated by introducing a carbon matrix into GeP₃ through high-energy ball milling, followed by encapsulating the resultant composite with graphene via a solution-based ultrasonic method. To delineate the individual role of carbon matrix and graphene, material characterization and electrochemical analyses were performed for GeP₃/C@rGO and three other samples: bare GeP₃, GeP₃ with graphene coating (GeP₃@rGO), and GeP₃ with carbon matrix (GeP₃/C). GeP₃/C@rGO exhibits the highest electric conductivity (5.89 × 10^-1 S cm^-1) and the largest surface area (167.85 m² g^-1) among the four samples. The as-prepared GeP₃/C@rGO delivered a reversible high capacity of 1084 mA h g^-1 at 50 mA g^-1, excellent rate capacity (435.4 mA h g^-1 at a high rate of 5 A g^-1), and long-term cycling stability (400 cycles with a reversible capacity of 823.3 mA h g^-1 at 0.2 A g^-1), all of which outperform the other three samples. The kinetics investigation reveals a "pseudocapacitive behavior" in GeP₃/C and GeP₃/C@rGO, where solely faradic reactions took place in bare GeP₃ and GeP₃@rGO with a typical "battery behavior". Based on ex-situ X-ray photoelectron spectroscopy and ex-situ electrochemical impedance spectroscopy, the carbon matrix serves to activate and stabilize the interior of the composite, while the graphene protects and restrains the exterior surface. Benefiting from the synergistic combination of these two components, GeP₃/C@rGO achieved extremely stable cycling stability as well as outstanding rate performance.

Hierarchical Tubular Architecture Constructed by Vertically Aligned CoS2 -MoS2 Nanosheets for Hydrogen Evolution Electrocatalysis

Developing efficient electrocatalysts for the hydrogen evolution reaction (HER) is crucial for establishing a sustainable and environmentally friendly energy system, but it is still a challenging issue. Herein, hierarchical tubular-structured CoS₂ -MoS₂ /C as efficient electrocatalysts are fabricated through a unique metal-organic framework (MOF) mediated self-sacrificial templating. Core-shell structured MoO₃ @ZIF-67 nanorods are used both as a precursor and a sacrificial template to form the one-dimensional tubular heterostructure where vertically aligned two-dimensional CoS₂ -MoS₂ nanosheets are formed on the MOF-derived carbon tube. Trace amounts of noble metals (Pd, Rh, and Ru) are successfully introduced to enhance the electrocatalytic property of the CoS₂ -MoS₂ /C nanocomposites. The as-synthesized hierarchical tubular heterostructures exhibit excellent HER catalytic performance owing to the merits of the hierarchical hollow architecture with abundantly exposed edges and the uniformly dispersed active sites. Impressively, the optimal Pd-CoS₂ -MoS₂ /C-600 catalyst delivers a current density of 10 mA cm^-2 at a low overpotential of 144 mV and a small Tafel slope of 59.9 mV/dec in 0.5 m H₂ SO₄ . Overall, this MOF-mediated strategy can be extended to the rational design and synthesis of other hollow heterogeneous catalysts for scalable hydrogen generation.

Practical MOF Nanoarchitectonics: New Strategies for Enhancing the Processability of MOFs for Practical Applications

Over the past decades, the development of porous materials has directly or indirectly affected industrial production methods. Metal-organic frameworks (MOFs) as an emerging class of porous materials exhibit some unique advantages, including controllable composition, a large surface area, high porosity, and so on. These attractive characteristics of MOFs have led to their potential applications in energy storage and conversion devices, drug delivery, adsorption and storage, sensors, and other areas. However, powdered MOFs have limited practical applications owing to poor processability, safety hazards from dust formation, and poor recyclability. In addition, the inherent micro/mesoporosities of MOFs also reduce the accessibility and diffusion kinetics for large molecules. To improve their processability for practical applications, MOFs are often deposited as MOF layers or films (i.e., MOF-coated composites) on supporting materials or are formed into 3D structured composites, such as aerogels and hydrogels. In this article, we review recent researches on these MOF composites, including their synthetic methods and potential applications in energy storage devices, heavy metal ion adsorption, and water purification. Finally, the future outlook and challenges associated with the large-scale fabrication of MOF-based composites for practical applications are discussed.

Mesoporous Iron-doped MoS2/CoMo2S4 Heterostructures through Organic-Metal Cooperative Interactions on Spherical Micelles for Electrochemical Water Splitting

Mesoporous metal sulfide hybrid (meso-MoS₂/CoMo₂S₄) materials via a soft-templating approach using diblock copolymer polystyrene-block-poly(acrylic acid) micelles are reported. The formation of the meso-MoS₂/CoMo₂S₄ heterostructures is based on the sophisticated coassembly of dithiooxamide and metal precursors (i.e., Co²⁺, PMo₁₂), which are subsequently annealed in nitrogen atmosphere to generate the mesoporous material. Decomposing the polymer leaves behind mesopores throughout the spherical MoS₂/CoMo₂S₄ hybrid particles, generating numerous electrochemical active sites in a network of pores that enable faster charge transfer and mass/gas diffusion that enhance the electrocatalytic performance of MoS₂/CoMo₂S₄. Doping the spherical meso-MoS₂/CoMo₂S₄ heterostructures with iron improves the electronic properties of the hybrid meso-Fe-MoS₂/CoMo₂S₄ material and consequently results in its superior electrochemical activities for both hydrogen evolution reaction and oxygen evolution reaction.

miRNa signature in small extracellular vesicles and their association with platinum resistance and cancer recurrence in ovarian cancer

Carboplatin, administered as a single drug or in combination with paclitaxel, is the standard chemotherapy treatment for patients with ovarian cancer (OVCA). Recent evidence suggests that miRNAs associated with small extracellular vesicles (sEVs) participate in the development of chemoresistance. We studied the effect of carboplatin in a heterogeneity population of OVCA cells and their derived sEVs to identify mechanisms associated with chemoresistance. sEVs were quantified using an engineered superparamagnetic material, gold-loaded ferric oxide nanotubes and a screen-printed electrode. miR-21-3p, miR-21-5p, and miR-891-5p are enriched in sEVs, and they contribute to carboplatin resistance in OVCA. Using a quantitative MS/MS, miR-21-5p activates glycolysis and increases the expression of ATP-binding cassette family and a detoxification enzyme. miR-21-3p and miR-891-5p increase the expression of proteins involved in DNA repair mechanisms. Interestingly, the levels of miR-891-5p within sEVs are significantly higher in patients at risk of ovarian cancer relapse. Identification of miRNAs in sEVs also provides the opportunity to track them in biological fluids to potentially determine patient response to chemotherapy.