Revealing the influence of in-situ formed LiCl on garnet/Li interface for dendrite-free solid-state batteries

Inadequate interfacial contact between lithium and solid-state electrolytes(SSEs)leads to elevated impedance and the growth of lithium dendrites,presenting significant obstacles to the practical viability of solid-state batteries(SSBs).To ameliorate interfacial contact,optimizing the surface treatment of SSEs has been widely adopted.However,the formation of LiCl through acid treatment,an equally crucial factor impacting SSB performance,has received limited attention,leaving its underlying mechanism unclear.Our study aims to shed light on SSE characteristics following LiCl formation and the removal of Li_(2)CO_(3) through acid treatment.We seek to establish quantifiable links between SSE surface structure and SSB performance,focusing on interfacial resistance,current distribution,critical current density(CCD),and lithium deposition.The formation of LiCl,occurring as Li_(2)CO_(3) is removed through acid treatment,effectively mitigates lithium dendrite formation on SSE surfaces.This action inhibits electron injection and reduces the diffusion rate of Li atoms.Simultaneously,acid treatment transforms the SSE surface into a lithiophilic state by eliminating surface Li_(2)CO_(3).Consequently,the interfacial resistance between lithium and SSEs substantially decreases from 487.67 to 35.99Ωcm^(2) at 25°C.This leads to a notably high CCD of 1.3 mA cm^(-2) and a significantly extended cycle life of 1,000 h.Furthermore,in full SSBs incorporating LiCoO_(2)cathodes and acid-treated garnet SSEs,we observe exceptional cyclability and rate capability.Our findings highlight that acid treatment not only establishes a fundamental relationship between SSE surfaces and battery performance but also offers an effective strategy for addressing interfacial challenges in SSBs.

Growth of BaTiO_3-Ag hybrid composite films at room temperature by aerosol deposition

Barium titanate (BaTiO3) and silver (Ag) composite film with high dielectric constant was grown at room temperature by an aerosol deposition method.The dielectric constant increases by 0.5 times after adding Ag to the BaTiO3 matrix,compared with pure BaTiO3.The high dielectric constant can be attributed to the percolation effect of Ag inclusions in the BaTiO3 matrix.The Ag was present in the form of discrete layer in the BaTiO3 film.The dielectric properties of BaTiO3 Ag were discussed in detail taking into account the changes in microstructures.

Optimally arranged TiO_(2)@MoS_(2) heterostructures with effectively induced built-in electric field for high-performance lithium-sulfur batteries

To overcome the serious technological issues affecting lithium-sulfur(Li-S) batteries,such as sluggish sulfur redox kinetics and the detrimental shuttle effect,heterostructure engineering has been investigated as a strategy to effectively capture soluble lithium polysulfide intermediates and promote their conversion reaction by integrating highly polar metal oxides with catalytically active metals sulfides.However,to fully exploit the outstanding properties of heterostructure-based composites,their detailed structure and interfacial contacts should be designed rationally.Herein,optimally arranged TiO_(2)and MoS_(2)-based heterostructures(TiO_(2)@MoS_(2)) are fabricated on carbon cloth as a multifunctional interlayer to efficiently trap polysulfide intermediates and accelerate their redox kinetics.Owing to the synergistic effects between TiO_(2)and MoS_(2)and the uniform heterointerface distribution that induces the ideally oriented built-in electric field,Li-S batteries with TiO_(2)@MoS_(2)interlayers exhibit high rate capability(601 mA h g^(-1)at 5 C),good cycling stability(capacity-fade rate of 0.067% per cycle over 500 cycles at2 C),and satisfactory areal capacity(5.2 mA h cm^(-2)) under an increased sulfur loading of 5.2 mg cm^(-2).Moreover,by comparing with a MoS_(2)@TiO_(2)interlayer composed of reversely arranged heterostructures,the effect of the built-in electric field’s direction on the electrocatalytic reactions of polysulfide intermediates is thoroughly investigated for the first time.The superior electrocatalytic activities of the rationally arranged TiO_(2)@MoS_(2)interlayer demonstrate the importance of optimizing the built-in electric field of heterostructures for producing high-performance Li-S batteries.

Homogenization on solution treatment and its effects on the precipitation-hardening of selective laser melted 17-4PH stainless steel

17-4 precipitation-hardened(PH)stainless steel(SS)exhibits high strength and good corrosion resistance via Cu-precipitation hardening.Unlike conventional wrought 17-4PH SS,Cu segregation andε-Cu pre-cipitates are observed in additively manufactured(AM)17-4PH SS owing to the repeated rapid cooling after heating,which characterizes the AM process.In this study,solution treatment was conducted under various temperatures(1,000,1,050,1,100,and 1,200℃)and durations(1,2,4,and 8 h)to minimize the negative effects of Cu segregation andε-Cu precipitates on precipitation hardening.The mechanical prop-erties and microstructures of each condition for the Cu precipitation behavior were examined.Although theε-Cu precipitates did not disappear after solution treatment,the average diameter of theε-Cu precipi-tates tended to decrease with increasing solution treatment temperature and duration.Therefore,solution treatment at a temperature of 1,200℃ for 8 h was the best,resulting in improved strength compared to the conventional solution treatment at 1,050℃.Solution treatment on at least 1,100℃ is effective in AM.

Efficient solar fuel production enabled by an iodide oxidation reaction on atomic layer deposited MoS_(2)

Oxygen evolution reaction(OER)as a half-anodic reaction of water splitting hinders the overall reaction efficiency owing to its thermodynamic and kinetic limitations.Iodide oxidation reaction(IOR)with low thermodynamic barrier and rapid reaction kinetics is a promising alternative to the OER.Herein,we present a molybdenum disulfide(MoS_(2))electrocatalyst for a high-efficiency and remarkably durable anode enabling IOR.MoS_(2)nanosheets deposited on a porous carbon paper via atomic layer deposition show an IOR current density of 10 mA cm^(–2)at an anodic potential of 0.63 V with respect to the reversible hydrogen electrode owing to the porous substrate as well as the intrinsic iodide oxidation capability of MoS_(2)as confirmed by theoretical calculations.The lower positive potential applied to the MoS_(2)-based heterostructure during IOR electrocatalysis prevents deterioration of the active sites on MoS_(2),resulting in exceptional durability of 200 h.Subsequently,we fabricate a two-electrode system comprising a MoS_(2)anode for IOR combined with a commercial Pt@C catalyst cathode for hydrogen evolution reaction.Moreover,the photovoltaic–electrochemical hydrogen production device comprising this electrolyzer and a single perovskite photovoltaic cell shows a record-high current density of 21 mA cm^(–2)at 1 sun under unbiased conditions.

Tailored BiVO_(4)/In_(2)O_(3)nanostructures with boosted charge separation ability toward unassisted water splitting

The development of new heterostructures with high photoactivity is a breakthrough for the limitation of solar-driven water splitting.Here,we first introduce indium oxide(In_(2)O_(3))nanorods(NRs)as a novel electron transport layer for bismuth vanadate(BiVO_(4))with a short charge diffusion length.In_(2)O_(3)NRs reinforce the electron transport and hole blocking of BiVO_(4),surpassing the state-of-the-art photoelectrochemical performances of BiVO_(4)-based photoanodes.Also,a tannin-nickel-iron complex(TANF)is used as an oxygen evolution catalyst to speed up the reaction kinetics.The final TANF/BiVO_(4)/In_(2)O_(3)NR photoanode generates photocurrent densities of 7.1 mAcm^(−2) in sulfite oxidation and 4.2 mA cm^(−2) in water oxidation at 1.23 V versus the reversible hydrogen electrode.Furthermore,the“artificial leaf,”which is a tandem cell with a perovskite/silicon solar cell,shows a solar-to-hydrogen conversion efficiency of 6.2%for unbiased solar water splitting.We reveal significant advances in the photoactivity of TANF/BiVO_(4)/In_(2)O_(3)NRs from the tailored nanostructure and band structure for charge dynamics.

A Kinetic Study on the Control of Nitrogen in Molten Slag and Metal

Nitrogen can easily contaminate molten steel during the steelmaking process and due to the low nitrogen capacity in slag, it is difficult to remove entrapped nitrogen from liquid steel. Degassing is often done to the steel at secondary steelmaking to lower the nitrogen content, but the control can often be kinetically limited by the steel grade and also the slag composition. Thus, a fundamental understanding of nitrogen dissolution into molten slag and metal including the rate of nitrogen dissolution can help in controlling nitrogen content in the final product.The kinetics of nitrogen dissolution in the molten calcium aluminate based slags and in molten steel with various element additions was investigated by measuring the 14N-15N isotope exchange reaction using a mass spectrometer at 1873 K.Results show that effect of elements on the rate constant of nitrogen dissolution such as Ni in Fe is relatively minimal similar to molybdenum. The surface rate constant of nitrogen dissolution in liquid Fe-10%Ni alloy was found to be 3.77×10-5 (mol/cm2·s·atm).The rate constant of nitrogen dissolution in the CaO-Al2O3-CaF2 slag was found to be wedge shaped, which decreased with increasing CaF2 to about 20 mol% followed by an increase through the rest of the CaF2 composition range. This was related to the effect of CaF2 on the structure of Al-O bonds for this slag.

Recent advances in electronic devices for monitoring and modulation of brain

The brain is actuated by billions of neurons with trillions of interconnections that regulate human behaviors.Understanding the mechanisms of these systems that induce sensory reactions and respond to disease remains one of the greatest challenges in science,engineering,and medicine.Recent advances in nanomaterials and nanotechnologies have led to the extensive research of electronic devices for brain interfaces to better understand the neural activities of the brains complex nervous system.The development of sensor devices for monitoring the physiological signals of the brain related to traumatic injury status has accompanied by the progress of electronic neural probes in parallel.In addition,these neurological and stereotactic surgical revolutions hold immense potential for clinical analysis of pharmacological systems within cerebral tissues.Here,we review the progress of electronic devices interfacing with brain in terms of the materials,fabrication technologies,and device designs.Neurophysiological activity can be measured and modulated by brain probes based on newly developed nanofabrication methodologies.Furthermore,in vivo pathological monitoring of the brain and pharmacological assessment has been developed in miniaturized and wireless form.We also consider the key challenges and prospects for further development,and explore the future directions emerging in the latest research.

喷墨油墨流变性能对其印刷适性的影响

喷墨印刷是一种可直接出版的印刷方式。喷墨印刷之所以能够实现,依靠的是油墨流体稳定、精准喷墨的印刷性能。本文通过观察墨滴形成的动态过程,研究喷墨印刷适性与油墨流变性能之间的内在联系。油墨的印刷适性是依照Ohnesorge(Oh)值的倒数Z来进行度量的,而Oh值与油墨的黏度、表面张力及浓度有关。考虑到墨滴的成形、定位的精准性及允许的最高喷墨频率,将Z值的可印刷范围重新定义在4～14之间。

Controlling the lateral and vertical dimensions of Bi2Se3 nanoplates via seeded growth

nanostructures 的形态学的调整经常是一项令人满意却挑战性的任务。我们采用了播种生长方法并且导致了运动控制综合双性人 < 潜水艇 class= “ a-plus-plus ” > 2 Se < 潜水艇 class= “ a-plus-plus ” > 有可修改的形态学的 3 nanoplates。由操作先锋答案与注射泵在被注入种子答案的率，二个特殊生长模式能被认识到。与快注射，双性人的厚度<潜水艇class=“ a-plus-plus ”> 2 Se <潜水艇class=“ a-plus-plus ”>当边长度从 160 nm (种子)长大了到 12 m 时， 3 nanoplates 稍微从 7.5 nm (种子)增加了到 9.5 nm ，在播种生长的 6 个连续回合以后。与慢注射，厚度和边长度分别地在 6 轮生长以后同时增加了到 35 nm 和 6 m。这二个模式能被看作在原子免职和表面移植之间的一场比赛。产品出现了有趣，厚度依赖者拉曼性质。另外， NIR 透明，高度传导性、灵活的双性人<潜水艇class=“ a-plus-plus ”> 2 Se <潜水艇class=“ a-plus-plus ”> 3 有不同厚度的薄电影被同样综合的双性人的集会构造<潜水艇class=“ a-plus-plus ”> 2 Se <潜水艇class=“ a-plus-plus ”> 3 nanoplates 。这条途径能显著地与多样的形态学基于播种生长和运动控制支持万用的 nanostructures 的发展。

Compositional dependence of thermophysical properties in binary alkaline earth borate melts:Insights from structure in short-range and intermediate-range order

In this work,the thermal conductivity of alkaline earth borate melts was measured using hot-wire method from 1323 to 1623 K,and the thermal diffusivity was extrapolated from the thermal conductivity and heat capacity.The compositional dependence of thermophysical properties was interpreted according to the structure in short-range and intermediate-range order.Based on the Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),and 11B magic-angle spinning nuclear magnetic resonance(MAS-NMR)spectra,modifier cation with higher field strength prefers the formation of non-bridging oxygens(NBOs)for the charge compensation at high BO_(1.5)/MO ratios.A lower amount of covalent bond and greater isolation of large borate groups lead to a lower thermal conductivity in calcium borate melt compared with strontium and barium borates.But the large size of Ba^(2+)encounters difficulty in fitting around B^[4]-OB^[4]linkages inside the overcrowded large borate groups when BO_(1.5)/BaO=2.5,promoting the formation of NBOs on the edge of borate groups for the charge compensation of modifier cations and leading to the decline in the thermal conductivity.Thermal conductivity plays a major role in regulating the thermal diffusivity at a given temperature since the compositional dependence of volumetric heat capacity is relatively weak compared with that of thermal conductivity.

Morphology Control of Bi2S3 Nanostructures and the Formation Mechanism

Bismuthinite （Bi2S3）nanostructures were prepared by a hydrothermal method with sodium ethylenediamine- tetraacetate （EDTA-Na2）. The morphology of Bi2S3 nanostructures was changed from a nanorod to a nanoplate by presence of the EDTA-Na2. The altered morphology was caused by the capping effect of EDTA-Na2 with Bi3＋ ions, which induces the suboptimal growth direction due to partially blocking the preferential orientation direction. When the EDTA-Na2/Bi3＋ molar ratio= 1, the growth of Bi2S3 nanostructures was not allowed due to the chelating effect of EDTA-Na2. The obtained Bi2S3 nanorods, stacked nanorods, nanoplates and nanoparticles were characterized using X-ray diffraction （XRD）, transmission electron microscopy （TEM）, high-resolution transmission electron mi- croscopy （HRTEM） and selected area electron diffraction （SAED） pattern. A possible formation mechanism of these morphologies was proposed. The successful synthesis of various morphologies of nanostructured Bi2S3 may open up new possibilities for thermoelectric, electronic and optoelectronic uses of nanodevices based on Bi2S3 nanostructure.

Massively parallel direct writing of nanoapertures using multi-optical probes and super-resolution near-fields

Laser direct-writing enables micro and nanoscale patterning,and is thus widely used for cutting-edge research and industrial applications.Various nanolithography methods,such as near-field,plasmonic,and scanning-probe lithography,are gaining increasing attention because they enable fabrication of high-resolution nanopatterns that are much smaller than the wavelength of light.However,conventional methods are limited by low throughput and scalability,and tend to use electron beams or focused-ion beams to create nanostructures.In this study,we developed a procedure for massively parallel direct writing of nanoapertures using a multi-optical probe system and superresolution near-fields.A glass micro-Fresnel zone plate array,which is an ultra-precision far-field optical system,was designed and fabricated as the multi-optical probe system.As a chalcogenide phase-change material(PCM),multiple layers of Sb_(65)Se_(35) were used to generate the super-resolution near-field effect.A nanoaperture was fabricated through direct laser writing on a large-area(200×200mm^(2))multi-layered PCM.A photoresist nanopattern was fabricated on an 8-inch wafer via near-field nanolithography using the developed nanoaperture and an i-line commercial exposure system.Unlike other methods,this technique allows high-throughput large-area nanolithography and overcomes the gap-control issue between the probe array and the patterning surface.

Spray deposited yttrium incorporated TiO_(2) photoelectrode for efficient photoelectrocatalytic degradation of organic pollutants

This work presents result on yttrium-doped titanium dioxide(YTO) thin films using a cost-effective spray pyrolysis technique for the photoelectrocatalytic degradation of phthalic acid(PA) and benzoic acid(BA).The physicochemical properties of YTO thin films were studied using X-ray diffraction,Raman spectroscopy,X-ray photoelectron spectroscopy,field-emission scanning electron microscopy,UV-vis spectroscopy,etc.The obtained results confirm the presence of yttrium in the host lattice.The band bending and flat band positions were studied using Mott-Schottky analysis.The film with 1% doping amount shows the highest degradation efficiency for both the model pollutants compared to TiO_(2).The stability of 1% YTO film confirms excellent performance analyzed by recycling tests using a UV-vis spectrophotometer.These results highlight the significance of rare earth metal doping in TiO_(2)for improved photoelectrocatalytic degradation efficiency.

A mass and energy estimation for the hydrogen utilization in the iron-making process

The possibility of using hydrogen to lower CO 2 emissions in the iron-making process was confirmed by the heat and mass balances in the blast furnace operation. The mass and heat balances for hydrogen utilization in the blast furnace were estimated by using the basic concept of RIST operating diagram. In this study, the RIST operating diagram was modified to be suitable for representing the operation with respect to hydrogen, where the RIST operating diagram is a graphical representation of heat and mass balance in blast furnace operation. RIST operating diagram was applied here to some individual parameters of interest such as H 2 injection in blast furnace process to reduce coke (carbon consumption). It was observed that the point W moved to the right in the RIST operating diagram under the condition of increasing hydrogen injection at tuyere, which originates from the contribution of gas composition (O/H 2 ) equilibrated with Fe/FeO at a certain temperature. Point P also moved downward due to heat requirement with respect to hydrogen utilization, by which the new RIST operating diagram for hydrogen utilization was able to be constructed. Under the condition of hydrogen injection, the expected overall carbon consumption in the blast furnace decreased due to the contribution of hydrogen.

Solution-processed highly adhesive graphene coatings for corrosion inhibition of metals

The corrosion of metals can be induced by different environmental and operational conditions,and protecting metals from corrosion is a serious concern in many applicatiions.The developme nt of new materials and/or tech no logies to improve the efficie ncy of anti-corrosi on coati ngs has attracted ren ewed in terest.In this study,we develop a protective coati ng composed of a bilayer structure of reduced graphe ne oxide(RGO)/graphene oxide(GO)applied to Cu plates by spray-coating and subsequent annealing.The annealing of the GO/Cu plates at 120℃produces a bilayer structure of RGO/GO by the partial reducti on of the spray-coated GO layer.This in duces superior corrosion resista nee and adhesi on strength compared to those of GO/Cu and RGO/Cu plates because of the hydrophobic n ature of the RGO surface exposed to the surroundings and the formation of Cu-O bonds with the O-based functional groups of GO.This approach provides a viable and scalable route for using graphene coatings to protect metal surfaces from corrosion.

Wireless phototherapeutic contact lenses and glasses with red light-emitting diodes

Light-mediated therapeutics have attracted considerable attention as a method for the treatment of ophthalmologic diseases,such as age-related macular degeneration,because of their non-invasiveness and the effectiveness to ameliorate the oxidative stress of retinal cells.However,the current phototherapeutic devices are opaque,bulky,and tethered forms,so they are not feasible for use in continuous treatment during the patient’s daily life.Herein,we report wireless,wearable phototherapeutic devices with red light-emitting diodes for continuous treatments.Red light-emitting diodes were formed to be conformal to three-dimensional surfaces of glasses and contact lenses.Furthermore,fabricated light-emitting diodes had either transparency or a miniaturized size so that the user’s view is not obstructed.Also,these devices were operated wirelessly with control of the light intensity.In addition,in-vitro and in-vivo tests using human retinal epithelial cells and a live rabbit demonstrated the effectiveness and reliable operation as phototherapeutic devices.

In situ thickness control of black phosphorus field-effect transistors via ozone treatment

A simple and reproducible method to control the thickness of black phosphorus flakes in real time using a UV/ozone treatment is demonstrated. Back-gated black phosphorus field-effect transistors （FETs） were fabricated using thick black phosphorus flakes obtained by thinning of black phosphorus, as oxygen radicals generated by UV irradiation formed phosphorus oxides on the surface. In order to monitor the thickness effect on the electrical properties, the fabricated FETs were loaded in the UV/ozone chamber, where both the optical （micro-Raman spectroscopy and optical microscopy） and electrical properties （current-voltage characteristics） were monitored in situ. We observed an intensity decrease of the Raman modes of black phosphorus while the field-effect mobility and on/off ratio increased by 48% and 6,800%, respectively. The instability in ambient air limits the investigation and implementation of ultra-thin black phosphorus. However, the method reported in this study allowed us to start with thick black phosphorous flakes, providing a reliable approach for optimizing the electrical performance of black phosphorus-based electronic devices. We believe that these results can motivate further studies using mono- and few-layer black phosphorus.

Zwitterion-assisted transition metal dichalcogenide nanosheets for scalable and biocompatible inkjet printing

Inkjet printing of two-dimensional(2D)transition metal dichalcogenide(TMD)nanosheets fabricated by liquid-phase exfoliation(LPE)allows simple,mass-producible,and low-cost photo-electronic devices.Many LPE processes involve toxic and environmentally hazardous solvents;however,dispersants have restricted the extent of applications of 2D-TMD inks.Herein,various 2D-TMD nanosheets,including MoS2,MoSe2,WS2,and WSe2,in addition to few-layered graphene,are inkjet-printed using a LPE process based on zwitterionic dispersants in water.Zwitterions with cationic and anionic species are water-soluble,while alkyl chain moieties associated with two ionic species adhere universally on the surface of TMD nanosheets,resulting in high throughput liquid exfoliation of the nanosheets.The zwitterion-assisted TMD nanosheets in water are successtully employed as an ink without the need for additives to adjust the viscosity and surface tension of the ink for use in an office inkjet printer;this gives rise to A4 scale,large-area inkjet-printed images on diverse substrates,such as metals,oxides,and polymer substrates patchable onto human skin.Combination with conductive graphene nanosheet inks allowed the development of mechanically flexible,biocompatible-printed arrays of photodetectors with pixelated MoSe2 channels on a paper exhibiting a photocurrent ON/OFF ratio of approximately 1038 and photocurrent switching of 500 ms.

Precise control of surface oxygen vacancies in ZnO nanoparticles for extremely high acetone sensing response

ZnO has been studied intensely for chemical sensors due to its high sensitivity and fast response.Here,we present a simple approach to precisely control oxygen vacancy contents to provide significantly enhanced acetone sensing performance of commercial ZnO nanopowders.A combination of H_(2)O_(2)treatment and thermal annealing produces optimal surface defects with oxygen vacancies on the ZnO nanoparticles(NPs).The highest response of~27,562 was achieved for 10 ppm acetone in 0.125 MH_(2)O_(2)treated/annealed ZnO NPs at the optimal working temperature of 400℃,which is significantly higher than that of reported so far in various acetone sensors based on metal oxide semiconductors(MOSs).Furthermore,first-principles calculations indicate that pre-adsorbed O formed on the surface of H_(2)O_(2)treated ZnO NPs can provide favorable adsorption energy,especially for acetone detection,due to strong bidentate bonding between carbonyl C atom of acetone molecules and pre-adsorbed O on the ZnO surface.Our study demonstrates that controlling surface oxygen vacancies by H_(2)O_(2)treatment and re-annealing at optimal temperature is an effective method to improve the sensing properties of commercial MOS materials.