Photocatalysis is a promising technology for purification of indoor air by oxidation of volatile organic compounds.This study provides a comprehensive analysis of the adsorption and photo-oxidation of surface-adsorbed...Photocatalysis is a promising technology for purification of indoor air by oxidation of volatile organic compounds.This study provides a comprehensive analysis of the adsorption and photo-oxidation of surface-adsorbed acetone on three SrTiO_(3)morphologies:cubes(for which exclusively{100}facets are exposed),{110}-truncated cubes,and{100}-truncated rhombic dodecahedrons,respectively,all prepared by hydrothermal synthesis.In situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy shows that cubic crystals contain a high quantity of surface-OH groups,enabling significant quantities of adsorbed acetone in the form ofη^(1)-enolate when exposed to gas phase acetone.Contrary,{110}facets exhibit fewer surface-OH groups,resulting in relatively small quantities of adsorbedη^(1)-acetone,without observable quantities of enolate.Interestingly,acetate and formate signatures appear in the spectra of cubic,surfaceη^(1)-enolate containing,SrTiO_(3)upon illumination,while besides acetate and formate,the formation of(surface)formaldehyde was observed on truncated cubes,and dodecahedrons,by conversion of adsorbedη^(1)-acetone.Time-Resolved Photoluminescence studies demonstrate that the lifetimes of photogenerated charge carriers vary with crystal morphology.The shortest carrier lifetime(τ_(1)=33±0.1 ps)was observed in{110}-truncated cube SrTiO_(3),likely due to a relatively strong built-in electric field promoting electron transport to{100}facets and hole transport to{110}facets.The second lifetime(τ_(2)=259±1 ps)was also the shortest for this morphology,possibly due to a higher amount of surface trap states.Our results demonstrate that SrTiO_(3)crystal morphology can be tuned to optimize performance in photocatalytic oxidation.展开更多
Core–shell nanoparticles containing plasmonic metals（Ag or Au） have been frequently reported to enhance performance of photo-electrochemical（PEC） devices. However, the stability of these particles in water-splitt...Core–shell nanoparticles containing plasmonic metals（Ag or Au） have been frequently reported to enhance performance of photo-electrochemical（PEC） devices. However, the stability of these particles in water-splitting conditions is usually not addressed. In this study we demonstrate that Ag@SiOcore–shell particles are instable in the acidic conditions in which WO-based PEC cells typically operate, Ag in the core being prone to oxidation, even if the SiOshell has a thickness in the order of 10 nm. This is evident from in situ voltammetry studies of several anode composites. Similar to the results of the PEC experiments, the Ag@SiOcore–shell particles are instable in slurry-based, Pt/ZnO induced photocatalytic water-splitting. This was evidenced by in situ photodeposition of Ag nanoparticles on the Pt-loaded ZnO catalyst, observed in TEM micrographs obtained after reaction. We explain the instability of Ag@SiOby OH-radical induced oxidation of Ag, yielding dissolved Ag+. Our results imply that a decrease in shell permeability for OH-radicals is necessary to obtain stable, Ag-based plasmonic entities in photo-electrochemical and photocatalytic water splitting.展开更多
Coherent anti-Stokes Raman scattering(CARS)microscopy is used to visualize the release of a model drug(theophylline)from a lipid(tripalmitin)based tablet during dissolution.The effects of transformation and dissolutio...Coherent anti-Stokes Raman scattering(CARS)microscopy is used to visualize the release of a model drug(theophylline)from a lipid(tripalmitin)based tablet during dissolution.The effects of transformation and dissolution of the drug are imaged in real time.This study reveals that the manufacturing process causes significant differences in the release process:tablets prepared from powder show formation of theophylline monohydrate on the surface which prevents a controlled drug release,whereas solid lipid extrudates did not show formation of monohydrate.This visualization technique can aid future tablet design.展开更多
Following publication of the original article[1],the authors reported that the author Hun-Gi Jung should be affiliated as 3,4 and 5 instead of 4 and 5.The author’s name“A.-Yeon Kim”needed to be updated to“A-Yeon ...Following publication of the original article[1],the authors reported that the author Hun-Gi Jung should be affiliated as 3,4 and 5 instead of 4 and 5.The author’s name“A.-Yeon Kim”needed to be updated to“A-Yeon Kim”,removing the period.The correct author’s name and affiliation have been provided in this Correction.The original article[1]has been corrected.展开更多
Micro RNA-26a(miR-26a)has been verified to promote osteogenic differentiation of mesenchymal stem cells in recent years.The main obstacles to its application in bone regeneration are instability in the physiological e...Micro RNA-26a(miR-26a)has been verified to promote osteogenic differentiation of mesenchymal stem cells in recent years.The main obstacles to its application in bone regeneration are instability in the physiological environment and low efficiency of cellular membrane penetration.To overcome these problems,we constructed a novel plant virus gene delivery system based on Cowpea chlorotic mottle virus(CCMV).By encapsulating miR-26a with purified capsid protein(CP)dimers derived from CCMV,CPmiR-26a(CP26a)virus-like particles(VLPs)were obtained.CP26a retained a structure similar to the native CCMV and protected miR-26a from digestion with its exterior CP.Moreover,CP26a featured similar cellular uptake efficiency,osteogenesis promotion ability,and better biocompatibility compared with Lipofectamine2000-miR-26a(lipo26a),which indicated a promising prospect for CCMV as a novel gene delivery system.展开更多
Apnoea,a major sleep disorder,affects many adults and causes several issues,such as fatigue,high blood pressure,liver conditions,increased risk of type II diabetes,and heart problems.Therefore,advanced monitoring and ...Apnoea,a major sleep disorder,affects many adults and causes several issues,such as fatigue,high blood pressure,liver conditions,increased risk of type II diabetes,and heart problems.Therefore,advanced monitoring and diagnosing tools of apnoea disorders are needed to facilitate better treatment,with advantages such as accuracy,comfort of use,cost effectiveness,and embedded computation capabilities to recognise,store,process,and transmit time series data.In this work we present an adaptation of our apnoea-Pi open-source surface acoustic wave(SAW)platform(Apnoea-Pi)to monitor and recognise apnoea in patients.The platform is based on a thin-film SAW device using bimorph ZnO and Al structures,including those fabricated as Al foils or plates,to achieve breath tracking based on humidity and temperature changes.We applied open-source electronics and provided embedded computing characteristics for signal processing,data recognition,storage,and transmission of breath signals.We show that the thin-film SAW device out-performed standard and off-the-shelf capacitive electronic sensors in terms of their response and accuracy for human breath-tracking purposes.This in combination with embedded electronics makes a suitable platform for human breath monitoring and sleep disorder recognition.展开更多
Additives in the electrolytes of Li-S batteries aim to increase overall capacity,improve Li ion conductivity,enhance cyclability,and mitigate the shuttle effect,which is one of the major issues of this system.Here,the...Additives in the electrolytes of Li-S batteries aim to increase overall capacity,improve Li ion conductivity,enhance cyclability,and mitigate the shuttle effect,which is one of the major issues of this system.Here,the use of water as an additive in the commonly used electrolyte,1.0 M LiTFSI/1.0%(w/w) LiNO_(3) and a 1:1 mixture of 1,3-dioxolane(DOL) and 1,2-dimethoxyethane(DME) was investigated.We used Co_(2)Mn_(0.5)Al_(0.5)O_(4)(CMA) as an electrocatalyst anchored on an activated carbon(AC) electrode with added sulfur via a melt-diffusion process.The structural analysis of CMA via Rietveld refinement showed interatomic spaces that can promote ionic conductivity,facilitating Li^(+) ion migration.Electrochemical tests determined 1600 ppm as the optimal water concentration,significantly reducing the shuttle effect.Post-mortem XPS analysis focused on the lithium metal anode revealed the formation of Li_(2)O layers in dry samples and LiOH in wet samples.Better capacity was observed in wet samples,which can be attributed to the superior ionic conductivity of LiOH at the electrode/electrolyte interface,surpassing that of Li_(2)O by 12 times.Finally,Operando FTIR experiments provided real-time insights into electrolyte degradation and SEI formation,elucidating the activity mechanisms of water and Li_(2)CO_(3) over the cycles.This work presents results that could aid future advancements in Li-S battery technology,offering possibilities to mitigate its challenges with inexpensive and scalable additives.展开更多
Chiral metamaterials(CMs)composed by artificial chiral resonators have attracted great attentions in the recent decades due to their strong chiroptical resonance and identifiable interaction with chiral materials,faci...Chiral metamaterials(CMs)composed by artificial chiral resonators have attracted great attentions in the recent decades due to their strong chiroptical resonance and identifiable interaction with chiral materials,facilitating practical applications in chiral biosensing,chiral emission,and display technology.However,the complex geometry of CMs improves the fabrication difficulty and hinders their scalable fabrication for practical applications,especially in the visible and ultraviolet wavelengths.One potential strategy is the colloidal lithography that enables parallel fabrication for scalable and various planar structures.Here,we demonstrate a stepwise colloidal lithography technique that uses sequential deposition from multiple CMs and expand their variety and complexity.The geometry and optical chirality of building blocks from single deposition are systematically investigated,and their combination enables a significant extension of the range of chiral patterns by multiple-step depositions.This approach resulted in a myriad of complex designs with different characteristic sizes,compositions,and shapes,which are particularly beneficial for the development of nanophotonic materials.In addition,we designed a flexible chiral device based on PDMS,which exhibits a good CD value and excellent stability even after multiple inward and outward bendings.The excellent compatibility to various substrates makes the planar CMs more flexible in practical applications in microfluidic biosensing.展开更多
This study explores the impact of introducing vacancy in the transition metal layer of rationally designed Na_(0.6)[Ni_(0.3)Ru_(0.3)Mn_(0.4)]O_(2)(NRM)cathode material.The incorporation of Ru,Ni,and vacancy enhances t...This study explores the impact of introducing vacancy in the transition metal layer of rationally designed Na_(0.6)[Ni_(0.3)Ru_(0.3)Mn_(0.4)]O_(2)(NRM)cathode material.The incorporation of Ru,Ni,and vacancy enhances the structural stability during extensive cycling,increases the operation voltage,and induces a capacity increase while also activating oxygen redox,respectively,in Na_(0.7)[Ni_(0.2)V_(Ni0.1)Ru_(0.3)Mn_(0.4)]O_(2)(V-NRM)compound.Various analytical techniques including transmission electron microscopy,X-ray absorption near edge spectroscopy,operando X-ray diffraction,and operando differential electrochemical mass spectrometry are employed to assess changes in the average oxidation states and structural distortions.The results demonstrate that V-NRM exhibits higher capacity than NRM and maintains a moderate capacity retention of 81%after 100 cycles.Furthermore,the formation of additional lone-pair electrons in the O 2p orbital enables V-NRM to utilize more capacity from the oxygen redox validated by density functional calculation,leading to a widened dominance of the OP4 phase without releasing O_(2) gas.These findings offer valuable insights for the design of advanced high-capacity cathode materials with improved performance and sustainability in sodium-ion batteries.展开更多
Our analysis presents an explanation of the Sun–Earth coupling mechanism during declining phase of a solar cycle,and how the dominant 13.5 and 27 day periods play roles in the coupling mechanism which led to intense ...Our analysis presents an explanation of the Sun–Earth coupling mechanism during declining phase of a solar cycle,and how the dominant 13.5 and 27 day periods play roles in the coupling mechanism which led to intense terrestrial magnetic storms during this declining phase compared to the rising phase of a solar cycle.Moreover,it is observed that while the 27 day period gets strongly modulated in the rising phase,the 13.5 day period modulation is more prominent during the declining phase.It is suggested that out of the 27 and 13.5 day periods of Sun–Earth interaction,the preferred period of modulation happens to be the one which is more dominant for the less random or quieter system participating in the coupling.It is reported for the first time that the 13.5 day period is more prominent in the Sun–Earth interaction during the declining phase of a solar cycle,as it is the most dominant period of Earth's magnetic system,which happens to be more persistent as a dynamical system and hence quieter or more receptive than the Sun.展开更多
The influence of water vapor on silica membrane with pore size of ,-4A has been investigated in terms of adsorption properties and percolation effect at 50 and 90 ℃. Two methods are employed： spectroscopic ellipsome...The influence of water vapor on silica membrane with pore size of ,-4A has been investigated in terms of adsorption properties and percolation effect at 50 and 90 ℃. Two methods are employed： spectroscopic ellipsometry for water vapor adsorption and gas permeation of binary mixture of helium and H2O The adsorption behaviors on the silica membrane comply with the first-order Langmuir isotherm. The investigation demonstrates that helium flux through the silica membrane decreases dramatically in presence of H20 molecules. The transport of gas molecules through such small pores is believed not to be continuous any more, whereas it is reasonably assumed that the gas molecules hop from one occupied site to another unoccupied one under the potential gradient. When the coverage of H20 molecules on the silica surface increases, the dramatic decrease of helium flux could be related to percolation effect, where the adsorbed H20 molecules on the silica surface block the hopping of helium molecules.展开更多
High-power tunable lasers are intensely pursued due to their vast application potential such as in telecom,ranging,and molecular sensing.Integrated photonics,however,is usually considered not suitable for high-power a...High-power tunable lasers are intensely pursued due to their vast application potential such as in telecom,ranging,and molecular sensing.Integrated photonics,however,is usually considered not suitable for high-power applications mainly due to its small size which limits the energy storage capacity and,therefore,the output power.In the late 90s,to improve the beam quality and increase the stored energy,large-mode-area(LMA)fibers were introduced in which the optical mode area is substantially large.Such LMA fibers have transformed the high-power capability of fiber systems ever since.Introducing such an LMA technology at the chip-scale can play an equally disruptive role with high power signal generation from an integrated photonics system.To this end,in this work we demonstrate such a technology,and show a very high-power tunable laser with the help of a silicon photonics based LMA power amplifier.We show output power reaching 1.8 W over a tunability range of 60 nm,spanning from 1.83μm to 1.89μm,limited only by the seed laser.Such an integrated LMA device can be used to substantially increase the power of the existing integrated tunable lasers currently limited to a few tens of milliwatts.The power levels demonstrated here reach and surpass that of many benchtop systems which truly makes the silicon photonics based integrated LMA device poised towards mass deployment for high power applications without relying on benchtop systems.展开更多
Most of the novel energy materials contain multiple elements occupying a single site in their lattice.The exceedingly large configurational space of these materials imposes challenges in determining low(est)energy str...Most of the novel energy materials contain multiple elements occupying a single site in their lattice.The exceedingly large configurational space of these materials imposes challenges in determining low(est)energy structures.Coulomb energies of possible configurations generally show a satisfactory correlation to computed energies at higher levels of theory and thus allow to screen for minimumenergy structures.Employing an expansion into a binary optimization problem,we obtain an efficient Coulomb energy optimizer using Monte Carlo and Genetic Algorithms.The presented optimization package,GOAC(Global Optimization of Atomistic Configurations by Coulomb),can achieve a speed up of several orders of magnitude compared to existing software.In this work,heuristic optimization on various material classes is performed.Thus,GOAC provides an efficient method for constructing low-energy atomistic models for ionic multi-element materials with gigantic configurational spaces.展开更多
Ensuring reliable and safe operation of high-power electronic devices necessitates the development of high-quality dielectric nano-capacitors with high recoverable energy density(URec)and efficiency(η)at low applied ...Ensuring reliable and safe operation of high-power electronic devices necessitates the development of high-quality dielectric nano-capacitors with high recoverable energy density(URec)and efficiency(η)at low applied electric fields(E)/voltages.In this work,we demonstrate ultra-high URec andηat low E<500 kV/cm in as-grown epitaxial relaxor ferroelectric(RFE)PMN-33PT films,rivaling those typically achieved in state-of-the-art RFE and antiferroelectric(AFE)materials.The high energy storage properties were achieved using a synergistic strategy involving large polarization,a giant built-in potential/imprint(five times higher than the coercive field),and AFE like behavior.The structural,chemical,and electrical investigations revealed that these achievements mainly arise from the effects of strain,dipole defects,and chemical composition.For instance,at low E,the capacitors exhibit under 160 kV/cm(i.e.,8 V)and 400 kV/cm(i.e.,20 V),respectively,an ultra-highΔP(45μC/cm^(2)and 60μC/cm^(2)),UE=URec/E(21 J·MV/cm^(2)and 17 J·MV/cm^(2)),and UF=URec/(1-η)(20 J/cm^(3)and 47 J/cm^(3))with a robust charge-discharge fatigue endurance and outstanding frequency and thermal stability.Additionally,the designed films exhibit outstanding energy storage performance at higher E up to 2 MV/cm(ΔP≈78μC/cm^(2),UE≈17.3 J·MV/cm^(2)and UF≈288 J/cm^(3))due to their low leakage current density.展开更多
In exploring the frontier of high-energy-density cathode materials for lithium-ion batteries,substantial progress has been made by fine-tuning the composition of Ni-rich cathodes tailored for high-capacity operation.E...In exploring the frontier of high-energy-density cathode materials for lithium-ion batteries,substantial progress has been made by fine-tuning the composition of Ni-rich cathodes tailored for high-capacity operation.Equally promising are Li-rich cathode materials,which leverage the novel mechanism of oxygen-redox chemistry to achieve enhanced capacities.Nonetheless,the practical realization of these capacities remains elusive,falling short of the desired benchmarks.In this work,we pioneer a Mn-based,Co-free,reduced-nickel,high-capacity cathode material:Li_(0.75)[Li_(0.15)Ni_(0.15)Mn 0.7]O_(2)ionic exchanged from Na_(0.75)[Li_(0.15)Ni_(0.15)Mn 0.7]O_(2).This material is an O_(2)-type layered structure,distinguished by honeycomb ordering within the transition-metal layer,as confirmed by comprehensive neutron and X-ray studies and extensive electrostatic screening.The material's unique structural integrity facilitates the delivery of an exceptional quantity of Li^(+)ions via O^(2-)/O_(2)^(n-)redox,circumventing oxygen release and phase transition.The de/lithiation process enables the delivery of a substantial reversible capacity of~284 mAh(g-oxide)^(-1)(956 Wh(kg-oxide)^(-1)).Moreover,this structural and chemical stability contributes to an acceptable cycling stability for 500 cycles in full cells,providing improved thermal stability with lower exothermic heat generation and thus highlighting the feasibility of a Mn-based,Co-free,reduced-nickel composition.This investigation marks a pivotal advancement in layered lithium cathode materials.展开更多
Silicon nitride(SiN)-on-SiO,attracts increasing interest in integrated photonics owing to its low propagation loss and wide transparency window,extending from^400 nm to 2350 nm.Scalable integration of active devices s...Silicon nitride(SiN)-on-SiO,attracts increasing interest in integrated photonics owing to its low propagation loss and wide transparency window,extending from^400 nm to 2350 nm.Scalable integration of active devices such as amplifiers and lasers on the Si;N,platform will enable applications requiring optical gain and a much-nceded alternative to hybrid integration,which suffers from high cost and lack of high-volume manufacturability.We demonstrate a high-gain optical amplifier in Al2O3:Er^3+ monolithically integrated on the Si3N4 platform using a double photonic layer approach.The device exhibits a net Si3N4-to-Si3N4 gain of 18.11±0.9 dB at 1532 nm,and a broadband gain operation over 70 nm covering wavelengths in the S-,C-and L-bands.This work shows that rare-carth-ion-doped materials and in particular,rare-earth-ion-doped Al.05,can provide very high net amplification for the Si3N4 platform,paving the way to the development of different active devices monolithically integrated in this passive platform.展开更多
Periodic noble metal nanoparticles offer a wide spectrum of applications including chemical and biological sensors,optical devices,and model catalysts due to their extraordinary properties.For sensing purposes and cat...Periodic noble metal nanoparticles offer a wide spectrum of applications including chemical and biological sensors,optical devices,and model catalysts due to their extraordinary properties.For sensing purposes and catalytic studies,substrates made of glass or fused-silica are normally required as supports,without the use of metallic adhesion layers.However,precise patterning of such uniform arrays of silica-supported noble metal nanoparticles,especially at sub-100 nm in diameter,is challenging without adhesion layers.In this paper,we report a robust method to large-scale fabricate highly ordered sub-20 nm noble metal nanoparticles,i.e.,gold and platinum,supported on silica substrates without adhesion layers,combining displacement Talbot lithography(DTL)with dry-etching techniques.Periodic photoresist nanocolumns at diameters of~110 nm are patterned on metal-coated oxidized silicon wafers using DTL,and subsequently transferred at a 1:1 ratio into anti-reflection layer coating(BARC)nanocolumns with the formation of nano-sharp tips,using nitrogen plasma etching.These BARC nanocolumns are then used as a mask for etching the deposited metal layer using inclined argon ion-beam etching.We find that increasing the etching time results in coneshaped silica features with metal nanoparticles on the tips at diameters ranging from 100 nm to sub-30 nm,over large areas of 3×3 cm^(2).Moreover,subsequent annealing these sub-30 nm metal nanoparticle arrays at high-temperature results in sub-20 nm metal nanoparticle arrays with~10^(10) uniform particles.展开更多
We report a robust fabrication method for patterning freestanding Pt nanowires for use as thermal anemometry probes for small-scale turbulence measurements.Using e-beam lithography,high aspect ratio Pt nanowires(~300 ...We report a robust fabrication method for patterning freestanding Pt nanowires for use as thermal anemometry probes for small-scale turbulence measurements.Using e-beam lithography,high aspect ratio Pt nanowires(~300 nm width,~70µm length,~100 nm thickness)were patterned on the surface of oxidized silicon(Si)wafers.Combining wet etching processes with dry etching processes,these Pt nanowires were successfully released,rendering them freestanding between two silicon dioxide(SiO2)beams supported on Si cantilevers.Moreover,the unique design of the bridge holding the device allowed gentle release of the device without damaging the Pt nanowires.The total fabrication time was minimized by restricting the use of e-beam lithography to the patterning of the Pt nanowires,while standard photolithography was employed for other parts of the devices.We demonstrate that the fabricated sensors are suitable for turbulence measurements when operated in constant-current mode.A robust calibration between the output voltage and the fluid velocity was established over the velocity range from 0.5 to 5 m s−1 in a SF6 atmosphere at a pressure of 2 bar and a temperature of 21°C.The sensing signal from the nanowires showed negligible drift over a period of several hours.Moreover,we confirmed that the nanowires can withstand high dynamic pressures by testing them in air at room temperature for velocities up to 55 m s−1.展开更多
Microfluidic systems enable automated and highly parallelized cell culture with low volumes and defined liquid dosing.To achieve this,systems typically integrate all functions into a single,monolithic device as a“one...Microfluidic systems enable automated and highly parallelized cell culture with low volumes and defined liquid dosing.To achieve this,systems typically integrate all functions into a single,monolithic device as a“one size fits all”solution.However,this approach limits the end users’(re)design flexibility and complicates the addition of new functions to the system.To address this challenge,we propose and demonstrate a modular and standardized plug-and-play fluidic circuit board(FCB)for operating microfluidic building blocks(MFBBs),whereby both the FCB and the MFBBs contain integrated valves.A single FCB can parallelize up to three MFBBs of the same design or operate MFBBs with entirely different architectures.The operation of the MFBBs through the FCB is fully automated and does not incur the cost of an extra external footprint.We use this modular platform to control three microfluidic large-scale integration(mLSI)MFBBs,each of which features 64 microchambers suitable for cell culturing with high spatiotemporal control.We show as a proof of principle that we can culture human umbilical vein endothelial cells(HUVECs)for multiple days in the chambers of this MFBB.Moreover,we also use the same FCB to control an MFBB for liquid dosing with a high dynamic range.Our results demonstrate that MFBBs with different designs can be controlled and combined on a single FCB.Our novel modular approach to operating an automated microfluidic system for parallelized cell culture will enable greater experimental flexibility and facilitate the cooperation of different chips from different labs.展开更多
基金Advanced Research Center for Chemical Building Blocks,ARC CBBC,which is co-foundedco-financed by the Dutch Research Council(NWO)and the Netherlands Ministry of Economic Affairs and Climate Policy.
文摘Photocatalysis is a promising technology for purification of indoor air by oxidation of volatile organic compounds.This study provides a comprehensive analysis of the adsorption and photo-oxidation of surface-adsorbed acetone on three SrTiO_(3)morphologies:cubes(for which exclusively{100}facets are exposed),{110}-truncated cubes,and{100}-truncated rhombic dodecahedrons,respectively,all prepared by hydrothermal synthesis.In situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy shows that cubic crystals contain a high quantity of surface-OH groups,enabling significant quantities of adsorbed acetone in the form ofη^(1)-enolate when exposed to gas phase acetone.Contrary,{110}facets exhibit fewer surface-OH groups,resulting in relatively small quantities of adsorbedη^(1)-acetone,without observable quantities of enolate.Interestingly,acetate and formate signatures appear in the spectra of cubic,surfaceη^(1)-enolate containing,SrTiO_(3)upon illumination,while besides acetate and formate,the formation of(surface)formaldehyde was observed on truncated cubes,and dodecahedrons,by conversion of adsorbedη^(1)-acetone.Time-Resolved Photoluminescence studies demonstrate that the lifetimes of photogenerated charge carriers vary with crystal morphology.The shortest carrier lifetime(τ_(1)=33±0.1 ps)was observed in{110}-truncated cube SrTiO_(3),likely due to a relatively strong built-in electric field promoting electron transport to{100}facets and hole transport to{110}facets.The second lifetime(τ_(2)=259±1 ps)was also the shortest for this morphology,possibly due to a higher amount of surface trap states.Our results demonstrate that SrTiO_(3)crystal morphology can be tuned to optimize performance in photocatalytic oxidation.
基金part of the research programme of the Foundation for Fundamental Research on Matter(FOM,project 10TBSC07-1),which is part of the Netherlands Organisation for Scientific Research(NWO)
文摘Core–shell nanoparticles containing plasmonic metals（Ag or Au） have been frequently reported to enhance performance of photo-electrochemical（PEC） devices. However, the stability of these particles in water-splitting conditions is usually not addressed. In this study we demonstrate that Ag@SiOcore–shell particles are instable in the acidic conditions in which WO-based PEC cells typically operate, Ag in the core being prone to oxidation, even if the SiOshell has a thickness in the order of 10 nm. This is evident from in situ voltammetry studies of several anode composites. Similar to the results of the PEC experiments, the Ag@SiOcore–shell particles are instable in slurry-based, Pt/ZnO induced photocatalytic water-splitting. This was evidenced by in situ photodeposition of Ag nanoparticles on the Pt-loaded ZnO catalyst, observed in TEM micrographs obtained after reaction. We explain the instability of Ag@SiOby OH-radical induced oxidation of Ag, yielding dissolved Ag+. Our results imply that a decrease in shell permeability for OH-radicals is necessary to obtain stable, Ag-based plasmonic entities in photo-electrochemical and photocatalytic water splitting.
基金supported by NanoNed,a nanotechnology program of the Dutch Ministry of Economic Affairs and partly financed by the Stichting voor Fundamenteel Onderzoek der Materie(FOM),which is financially supported by the Nederlandse Organisatie voor Wetenschappelijk Onderzoek(NWO).The Marie Curie Fellowship and the Galenos Network are acknowledged for financial support(MEST-CT-2004-404992).
文摘Coherent anti-Stokes Raman scattering(CARS)microscopy is used to visualize the release of a model drug(theophylline)from a lipid(tripalmitin)based tablet during dissolution.The effects of transformation and dissolution of the drug are imaged in real time.This study reveals that the manufacturing process causes significant differences in the release process:tablets prepared from powder show formation of theophylline monohydrate on the surface which prevents a controlled drug release,whereas solid lipid extrudates did not show formation of monohydrate.This visualization technique can aid future tablet design.
文摘Following publication of the original article[1],the authors reported that the author Hun-Gi Jung should be affiliated as 3,4 and 5 instead of 4 and 5.The author’s name“A.-Yeon Kim”needed to be updated to“A-Yeon Kim”,removing the period.The correct author’s name and affiliation have been provided in this Correction.The original article[1]has been corrected.
基金supported by the research funding from West China School/Hospital of Stomatology,Sichuan University(Nos.RCDWJS2021-15,RD-03-202010,RD-02-202004)the research funding from the State Key Laboratory of Oral Diseases(No.SKLOD202111)the fellowship of China Postdoctoral Science Foundation(No.2020TQ0211)。
文摘Micro RNA-26a(miR-26a)has been verified to promote osteogenic differentiation of mesenchymal stem cells in recent years.The main obstacles to its application in bone regeneration are instability in the physiological environment and low efficiency of cellular membrane penetration.To overcome these problems,we constructed a novel plant virus gene delivery system based on Cowpea chlorotic mottle virus(CCMV).By encapsulating miR-26a with purified capsid protein(CP)dimers derived from CCMV,CPmiR-26a(CP26a)virus-like particles(VLPs)were obtained.CP26a retained a structure similar to the native CCMV and protected miR-26a from digestion with its exterior CP.Moreover,CP26a featured similar cellular uptake efficiency,osteogenesis promotion ability,and better biocompatibility compared with Lipofectamine2000-miR-26a(lipo26a),which indicated a promising prospect for CCMV as a novel gene delivery system.
基金financially supported by the UK Engineering and Physical Sciences Research Council (EPSRC) under grant EP/P018998/1the UK Fluidic Network Special Interest Group of Acoustofluidics (EP/N032861/1).
文摘Apnoea,a major sleep disorder,affects many adults and causes several issues,such as fatigue,high blood pressure,liver conditions,increased risk of type II diabetes,and heart problems.Therefore,advanced monitoring and diagnosing tools of apnoea disorders are needed to facilitate better treatment,with advantages such as accuracy,comfort of use,cost effectiveness,and embedded computation capabilities to recognise,store,process,and transmit time series data.In this work we present an adaptation of our apnoea-Pi open-source surface acoustic wave(SAW)platform(Apnoea-Pi)to monitor and recognise apnoea in patients.The platform is based on a thin-film SAW device using bimorph ZnO and Al structures,including those fabricated as Al foils or plates,to achieve breath tracking based on humidity and temperature changes.We applied open-source electronics and provided embedded computing characteristics for signal processing,data recognition,storage,and transmission of breath signals.We show that the thin-film SAW device out-performed standard and off-the-shelf capacitive electronic sensors in terms of their response and accuracy for human breath-tracking purposes.This in combination with embedded electronics makes a suitable platform for human breath monitoring and sleep disorder recognition.
基金the financial support from the Brazilian funding agencies FAPESP. (2024/01031-1, 2022/022220, 2020/04281-8, 21/14442-1, 17/11986-5)support from FAPESP through the research project Pi (2022/02901-4)+2 种基金CAPES (1740195)CNPq through the research grant (313672/2021-0)support Shell and the strategic importance of the support given by ANP (Brazil’s National Oil, Natural Gas and Biofuels Agency) through the R & D levy regulation。
文摘Additives in the electrolytes of Li-S batteries aim to increase overall capacity,improve Li ion conductivity,enhance cyclability,and mitigate the shuttle effect,which is one of the major issues of this system.Here,the use of water as an additive in the commonly used electrolyte,1.0 M LiTFSI/1.0%(w/w) LiNO_(3) and a 1:1 mixture of 1,3-dioxolane(DOL) and 1,2-dimethoxyethane(DME) was investigated.We used Co_(2)Mn_(0.5)Al_(0.5)O_(4)(CMA) as an electrocatalyst anchored on an activated carbon(AC) electrode with added sulfur via a melt-diffusion process.The structural analysis of CMA via Rietveld refinement showed interatomic spaces that can promote ionic conductivity,facilitating Li^(+) ion migration.Electrochemical tests determined 1600 ppm as the optimal water concentration,significantly reducing the shuttle effect.Post-mortem XPS analysis focused on the lithium metal anode revealed the formation of Li_(2)O layers in dry samples and LiOH in wet samples.Better capacity was observed in wet samples,which can be attributed to the superior ionic conductivity of LiOH at the electrode/electrolyte interface,surpassing that of Li_(2)O by 12 times.Finally,Operando FTIR experiments provided real-time insights into electrolyte degradation and SEI formation,elucidating the activity mechanisms of water and Li_(2)CO_(3) over the cycles.This work presents results that could aid future advancements in Li-S battery technology,offering possibilities to mitigate its challenges with inexpensive and scalable additives.
基金This study was financially supported by the International Science and Technology Innovation Cooperation of Sichuan Province(No.21GJHZ0230)the National Natural Science Foundation of China(No.11604227)+1 种基金the International Visiting Program for Excellent Young Scholars of SCU(No.20181504)the Tenure Track program of the University of Twente.
文摘Chiral metamaterials(CMs)composed by artificial chiral resonators have attracted great attentions in the recent decades due to their strong chiroptical resonance and identifiable interaction with chiral materials,facilitating practical applications in chiral biosensing,chiral emission,and display technology.However,the complex geometry of CMs improves the fabrication difficulty and hinders their scalable fabrication for practical applications,especially in the visible and ultraviolet wavelengths.One potential strategy is the colloidal lithography that enables parallel fabrication for scalable and various planar structures.Here,we demonstrate a stepwise colloidal lithography technique that uses sequential deposition from multiple CMs and expand their variety and complexity.The geometry and optical chirality of building blocks from single deposition are systematically investigated,and their combination enables a significant extension of the range of chiral patterns by multiple-step depositions.This approach resulted in a myriad of complex designs with different characteristic sizes,compositions,and shapes,which are particularly beneficial for the development of nanophotonic materials.In addition,we designed a flexible chiral device based on PDMS,which exhibits a good CD value and excellent stability even after multiple inward and outward bendings.The excellent compatibility to various substrates makes the planar CMs more flexible in practical applications in microfluidic biosensing.
基金supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education,Science and Technology(NRF-2020R1A6A1A03043435,NRF-2023R1A2C2003210,and NRF-2022M3H4A1A04096478)by Technology Innovation Program(Alchemist Project,20012196,Al based supercritical materials discovery)funded by the Ministry of Trade,Industry&Energy,Korea.support from the“Bundesministerium fur Bildung und Forschung”(BMBF)and the computing time granted through JARA-HPC on the supercomputer JURECA at Forschungszentrum Julich.
文摘This study explores the impact of introducing vacancy in the transition metal layer of rationally designed Na_(0.6)[Ni_(0.3)Ru_(0.3)Mn_(0.4)]O_(2)(NRM)cathode material.The incorporation of Ru,Ni,and vacancy enhances the structural stability during extensive cycling,increases the operation voltage,and induces a capacity increase while also activating oxygen redox,respectively,in Na_(0.7)[Ni_(0.2)V_(Ni0.1)Ru_(0.3)Mn_(0.4)]O_(2)(V-NRM)compound.Various analytical techniques including transmission electron microscopy,X-ray absorption near edge spectroscopy,operando X-ray diffraction,and operando differential electrochemical mass spectrometry are employed to assess changes in the average oxidation states and structural distortions.The results demonstrate that V-NRM exhibits higher capacity than NRM and maintains a moderate capacity retention of 81%after 100 cycles.Furthermore,the formation of additional lone-pair electrons in the O 2p orbital enables V-NRM to utilize more capacity from the oxygen redox validated by density functional calculation,leading to a widened dominance of the OP4 phase without releasing O_(2) gas.These findings offer valuable insights for the design of advanced high-capacity cathode materials with improved performance and sustainability in sodium-ion batteries.
基金MOTA for providing a fellowship under the NFST projectIISER,Kolkata for providing all necessary support。
文摘Our analysis presents an explanation of the Sun–Earth coupling mechanism during declining phase of a solar cycle,and how the dominant 13.5 and 27 day periods play roles in the coupling mechanism which led to intense terrestrial magnetic storms during this declining phase compared to the rising phase of a solar cycle.Moreover,it is observed that while the 27 day period gets strongly modulated in the rising phase,the 13.5 day period modulation is more prominent during the declining phase.It is suggested that out of the 27 and 13.5 day periods of Sun–Earth interaction,the preferred period of modulation happens to be the one which is more dominant for the less random or quieter system participating in the coupling.It is reported for the first time that the 13.5 day period is more prominent in the Sun–Earth interaction during the declining phase of a solar cycle,as it is the most dominant period of Earth's magnetic system,which happens to be more persistent as a dynamical system and hence quieter or more receptive than the Sun.
基金This work was supported by the Fhndamental Research Funds for the Central Universities （No.XDJK2015C002） and the National Natural Science Foundation of China （No.51402243）. Special thanks are given to Prof. H. J. M Bouwmeester and Dr. N.E. Benes from University of Twente for fruitful discussion.
文摘The influence of water vapor on silica membrane with pore size of ,-4A has been investigated in terms of adsorption properties and percolation effect at 50 and 90 ℃. Two methods are employed： spectroscopic ellipsometry for water vapor adsorption and gas permeation of binary mixture of helium and H2O The adsorption behaviors on the silica membrane comply with the first-order Langmuir isotherm. The investigation demonstrates that helium flux through the silica membrane decreases dramatically in presence of H20 molecules. The transport of gas molecules through such small pores is believed not to be continuous any more, whereas it is reasonably assumed that the gas molecules hop from one occupied site to another unoccupied one under the potential gradient. When the coverage of H20 molecules on the silica surface increases, the dramatic decrease of helium flux could be related to percolation effect, where the adsorbed H20 molecules on the silica surface block the hopping of helium molecules.
基金supported by EU Horizon 2020 Framework Programme—Grant Agreement No.:965124(FEMTOCHIP)Deutsche Forschungsgemeinschaft(SP2111)contract number PACE:Ka908/10-1Open Access funding enabled and organized by Projekt DEAL.
文摘High-power tunable lasers are intensely pursued due to their vast application potential such as in telecom,ranging,and molecular sensing.Integrated photonics,however,is usually considered not suitable for high-power applications mainly due to its small size which limits the energy storage capacity and,therefore,the output power.In the late 90s,to improve the beam quality and increase the stored energy,large-mode-area(LMA)fibers were introduced in which the optical mode area is substantially large.Such LMA fibers have transformed the high-power capability of fiber systems ever since.Introducing such an LMA technology at the chip-scale can play an equally disruptive role with high power signal generation from an integrated photonics system.To this end,in this work we demonstrate such a technology,and show a very high-power tunable laser with the help of a silicon photonics based LMA power amplifier.We show output power reaching 1.8 W over a tunability range of 60 nm,spanning from 1.83μm to 1.89μm,limited only by the seed laser.Such an integrated LMA device can be used to substantially increase the power of the existing integrated tunable lasers currently limited to a few tens of milliwatts.The power levels demonstrated here reach and surpass that of many benchtop systems which truly makes the silicon photonics based integrated LMA device poised towards mass deployment for high power applications without relying on benchtop systems.
基金The presented work was carried out within the framework of the Helmholtz Association’s program Materials and Technologies for the Energy Transition,Topic 2:Electrochemical Energy Storage.Computation time granted through JARA HPC on the supercomputer JURECA93 at Forschungszentrum Jülich under Grant No.jiek12 is gratefully acknowledged by the authorsK.K.and P.K.thank for the financial support from the“Deutsche Forschungsgemeinschaft”(DFG,German Research Foundation)under project No.501562980.
文摘Most of the novel energy materials contain multiple elements occupying a single site in their lattice.The exceedingly large configurational space of these materials imposes challenges in determining low(est)energy structures.Coulomb energies of possible configurations generally show a satisfactory correlation to computed energies at higher levels of theory and thus allow to screen for minimumenergy structures.Employing an expansion into a binary optimization problem,we obtain an efficient Coulomb energy optimizer using Monte Carlo and Genetic Algorithms.The presented optimization package,GOAC(Global Optimization of Atomistic Configurations by Coulomb),can achieve a speed up of several orders of magnitude compared to existing software.In this work,heuristic optimization on various material classes is performed.Thus,GOAC provides an efficient method for constructing low-energy atomistic models for ionic multi-element materials with gigantic configurational spaces.
基金supported by the Slovenian Research Agency(Nos.P2-0091,J2-2510,N2-0187,N2-0149,and P1-0125)the Swiss National Science Foundation(Lead Agency Grant No.192047)the Region Hauts-de-France(Projects TERRA(AAP STARS-N°21002758)and TRANSITION(CPER MANIFEST-N°22006563)).
文摘Ensuring reliable and safe operation of high-power electronic devices necessitates the development of high-quality dielectric nano-capacitors with high recoverable energy density(URec)and efficiency(η)at low applied electric fields(E)/voltages.In this work,we demonstrate ultra-high URec andηat low E<500 kV/cm in as-grown epitaxial relaxor ferroelectric(RFE)PMN-33PT films,rivaling those typically achieved in state-of-the-art RFE and antiferroelectric(AFE)materials.The high energy storage properties were achieved using a synergistic strategy involving large polarization,a giant built-in potential/imprint(five times higher than the coercive field),and AFE like behavior.The structural,chemical,and electrical investigations revealed that these achievements mainly arise from the effects of strain,dipole defects,and chemical composition.For instance,at low E,the capacitors exhibit under 160 kV/cm(i.e.,8 V)and 400 kV/cm(i.e.,20 V),respectively,an ultra-highΔP(45μC/cm^(2)and 60μC/cm^(2)),UE=URec/E(21 J·MV/cm^(2)and 17 J·MV/cm^(2)),and UF=URec/(1-η)(20 J/cm^(3)and 47 J/cm^(3))with a robust charge-discharge fatigue endurance and outstanding frequency and thermal stability.Additionally,the designed films exhibit outstanding energy storage performance at higher E up to 2 MV/cm(ΔP≈78μC/cm^(2),UE≈17.3 J·MV/cm^(2)and UF≈288 J/cm^(3))due to their low leakage current density.
基金supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education,Science and Technology(NRF-2022R1F1A1063351 and RS-2024-00446825).
文摘In exploring the frontier of high-energy-density cathode materials for lithium-ion batteries,substantial progress has been made by fine-tuning the composition of Ni-rich cathodes tailored for high-capacity operation.Equally promising are Li-rich cathode materials,which leverage the novel mechanism of oxygen-redox chemistry to achieve enhanced capacities.Nonetheless,the practical realization of these capacities remains elusive,falling short of the desired benchmarks.In this work,we pioneer a Mn-based,Co-free,reduced-nickel,high-capacity cathode material:Li_(0.75)[Li_(0.15)Ni_(0.15)Mn 0.7]O_(2)ionic exchanged from Na_(0.75)[Li_(0.15)Ni_(0.15)Mn 0.7]O_(2).This material is an O_(2)-type layered structure,distinguished by honeycomb ordering within the transition-metal layer,as confirmed by comprehensive neutron and X-ray studies and extensive electrostatic screening.The material's unique structural integrity facilitates the delivery of an exceptional quantity of Li^(+)ions via O^(2-)/O_(2)^(n-)redox,circumventing oxygen release and phase transition.The de/lithiation process enables the delivery of a substantial reversible capacity of~284 mAh(g-oxide)^(-1)(956 Wh(kg-oxide)^(-1)).Moreover,this structural and chemical stability contributes to an acceptable cycling stability for 500 cycles in full cells,providing improved thermal stability with lower exothermic heat generation and thus highlighting the feasibility of a Mn-based,Co-free,reduced-nickel composition.This investigation marks a pivotal advancement in layered lithium cathode materials.
基金Stichting voor de Technische Werenschappen(STW)(STW-13536)Optical Sciences Group ar University of Twente.
文摘Silicon nitride(SiN)-on-SiO,attracts increasing interest in integrated photonics owing to its low propagation loss and wide transparency window,extending from^400 nm to 2350 nm.Scalable integration of active devices such as amplifiers and lasers on the Si;N,platform will enable applications requiring optical gain and a much-nceded alternative to hybrid integration,which suffers from high cost and lack of high-volume manufacturability.We demonstrate a high-gain optical amplifier in Al2O3:Er^3+ monolithically integrated on the Si3N4 platform using a double photonic layer approach.The device exhibits a net Si3N4-to-Si3N4 gain of 18.11±0.9 dB at 1532 nm,and a broadband gain operation over 70 nm covering wavelengths in the S-,C-and L-bands.This work shows that rare-carth-ion-doped materials and in particular,rare-earth-ion-doped Al.05,can provide very high net amplification for the Si3N4 platform,paving the way to the development of different active devices monolithically integrated in this passive platform.
基金This work was supported by the Netherlands Center for Multiscale Catalytic Energy Conversion(MCEC)。
文摘Periodic noble metal nanoparticles offer a wide spectrum of applications including chemical and biological sensors,optical devices,and model catalysts due to their extraordinary properties.For sensing purposes and catalytic studies,substrates made of glass or fused-silica are normally required as supports,without the use of metallic adhesion layers.However,precise patterning of such uniform arrays of silica-supported noble metal nanoparticles,especially at sub-100 nm in diameter,is challenging without adhesion layers.In this paper,we report a robust method to large-scale fabricate highly ordered sub-20 nm noble metal nanoparticles,i.e.,gold and platinum,supported on silica substrates without adhesion layers,combining displacement Talbot lithography(DTL)with dry-etching techniques.Periodic photoresist nanocolumns at diameters of~110 nm are patterned on metal-coated oxidized silicon wafers using DTL,and subsequently transferred at a 1:1 ratio into anti-reflection layer coating(BARC)nanocolumns with the formation of nano-sharp tips,using nitrogen plasma etching.These BARC nanocolumns are then used as a mask for etching the deposited metal layer using inclined argon ion-beam etching.We find that increasing the etching time results in coneshaped silica features with metal nanoparticles on the tips at diameters ranging from 100 nm to sub-30 nm,over large areas of 3×3 cm^(2).Moreover,subsequent annealing these sub-30 nm metal nanoparticle arrays at high-temperature results in sub-20 nm metal nanoparticle arrays with~10^(10) uniform particles.
基金This work is supported by the Max Planck-University of Twente Center for Complex Fluid Dynamics and by the Netherlands Organisation for Scientific Research(NWO)Gravitation program funded by the Ministry of Education,Culture and Science of the government of the Netherlands.
文摘We report a robust fabrication method for patterning freestanding Pt nanowires for use as thermal anemometry probes for small-scale turbulence measurements.Using e-beam lithography,high aspect ratio Pt nanowires(~300 nm width,~70µm length,~100 nm thickness)were patterned on the surface of oxidized silicon(Si)wafers.Combining wet etching processes with dry etching processes,these Pt nanowires were successfully released,rendering them freestanding between two silicon dioxide(SiO2)beams supported on Si cantilevers.Moreover,the unique design of the bridge holding the device allowed gentle release of the device without damaging the Pt nanowires.The total fabrication time was minimized by restricting the use of e-beam lithography to the patterning of the Pt nanowires,while standard photolithography was employed for other parts of the devices.We demonstrate that the fabricated sensors are suitable for turbulence measurements when operated in constant-current mode.A robust calibration between the output voltage and the fluid velocity was established over the velocity range from 0.5 to 5 m s−1 in a SF6 atmosphere at a pressure of 2 bar and a temperature of 21°C.The sensing signal from the nanowires showed negligible drift over a period of several hours.Moreover,we confirmed that the nanowires can withstand high dynamic pressures by testing them in air at room temperature for velocities up to 55 m s−1.
基金This work was supported by the VESCEL ERC Advanced Grant to A.van den Berg(grant No.669768)the MFManufacturing ESCEL Joint Undertaking(grant No.621275-2)。
文摘Microfluidic systems enable automated and highly parallelized cell culture with low volumes and defined liquid dosing.To achieve this,systems typically integrate all functions into a single,monolithic device as a“one size fits all”solution.However,this approach limits the end users’(re)design flexibility and complicates the addition of new functions to the system.To address this challenge,we propose and demonstrate a modular and standardized plug-and-play fluidic circuit board(FCB)for operating microfluidic building blocks(MFBBs),whereby both the FCB and the MFBBs contain integrated valves.A single FCB can parallelize up to three MFBBs of the same design or operate MFBBs with entirely different architectures.The operation of the MFBBs through the FCB is fully automated and does not incur the cost of an extra external footprint.We use this modular platform to control three microfluidic large-scale integration(mLSI)MFBBs,each of which features 64 microchambers suitable for cell culturing with high spatiotemporal control.We show as a proof of principle that we can culture human umbilical vein endothelial cells(HUVECs)for multiple days in the chambers of this MFBB.Moreover,we also use the same FCB to control an MFBB for liquid dosing with a high dynamic range.Our results demonstrate that MFBBs with different designs can be controlled and combined on a single FCB.Our novel modular approach to operating an automated microfluidic system for parallelized cell culture will enable greater experimental flexibility and facilitate the cooperation of different chips from different labs.
