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Despite the continuously increased requirement on automated synthesis of medicines for distributed manufacturing and personal care, it remains a challenge to realize automated synthesis which requires solid-liquid phase reactions. In this work, we demonstrated an automated solid-liquid synthesis for gadopentetate dimeglumine, the most widely used magnetic resonance imaging (MRI) contrast agent. The high-efficiency reaction was performed in a 3D microfluidic chip which was fabricated by femtosecond laser micromachining. The structure of the chip realized 3D shear flow which was essential for highly efficient mixing and movement of the solid-liquid mixtures. Ultraviolet visible (UV–vis) spectrometer was employed for in-line analysis to help automation of this system. Comparing with the round-bottom flask system, this synthetic system showed significantly higher reaction rate, indicating the advantage of the 3D microfluidic technology in micro chemical engineering.

Mineralization of the ZIF-8 in the presence of biomacromolecules has been demonstrated to be a general way for making bioentities@ZIFs composites. The ZIF-8 crystals permit controlled storage and utilization of the bioentities, thus can benefit drug delivery, cold-chain breaking etc. With the increasing needs on personal care and distributed manufacturing, automated synthesis controlled by a computer becomes the next challenge. In this work, we designed an automatic synthesis system to prepare PEG mineralized ZIF-8 composite particles. This system is based on flow chemistry with the microfluidic chips fabricated by femtosecond laser micromachining. The particles were synthesized and monitored automatically. Furthermore, this synthesizer could be extended for fabrication of vaccine particles under remote control through internet.

A series of hollow structured CuCeOx composite catalysts with different Cu/Ce molar ratios were synthesized via a simple hydrothermal approach, which were applied in catalytic combustion of toluene. The XRD and Raman results indicate that partial of Cu ions are incorporated into CeO2 lattice, forming Cu-O-Ce solid solution. This strengthens the synergistic interaction between CuO and CeO2, enhancing the amounts of oxygen vacancies and low-temperature reducibility. Among the serial catalysts, the Cu6Ce4Ox catalyst exhibits superior catalytic performance, and its 90% conversion (T90) is 260 ℃. The high surface area, low-temperature reducibility, and abundant surface active oxygen species are main factors for superior catalytic performance. The DRIFTs result further clarifies the possible pathway for toluene oxidation, that toluene is converted via benzyl alcohol, benzaldehyde, and benzoate species as main intermediates and is finally decomposed to CO2 and H2O.

This study investigates the atomization process of a liquid jet in supersonic crossflow at a Mach number of 2.1 by using a multi-scale simulation method. This hybrid numerical method can realize accurate simulation of the primary and secondary breakup of the liquid jet with large scale instabilities and small droplet dynamics under compressible supersonic crossflow. The Eulerian framework is applied for capturing the gas-liquid interface by a coupled Level set and Volume-of-fluid (CLSVOF) method. Based on the Delayed Detached Eddy Simulation (DDES), the adaptive mesh refinement (AMR) method is introduced to predict the breakup of liquid column, blocks and filaments. The Lagrangian framework is applied for the dispersed droplets generated under the conversion criteria during the atomization process. The hybrid CLSVOF-LPT method can greatly reduce the loss of liquid phase mass and save computing resources. The distribution morphology of droplets in a cross-sectional plane from the simulation agreed well with the experimental data. Besides, the trends of the jet trajectory and primary breakup behavior of liquid column are well captured.

Two-dimensional flow of the pulsed co-flow jet (CFJ) and the influence of the pulsed parameters on the lift and power consumption are investigated numerically. Firstly, the jet channel of traditional CFJ airfoil is improved. The stall margin is increased by 3° compared with the corresponding traditional CFJ airfoil, and the lift is increased, while the drag is reduced significantly. Then, the influence of the pulsed parameters, such as the pulse waveform, including sinusoidal and rectangular waves, the duty cycle, and the pulse frequency on the lift and power consumption are presented and analyzed in detail. It is concluded that, compared with the steady CFJ, the pulsed CFJ possesses much better ability in suppressing separation and can improve the lift characteristics significantly with limited cost of power consumption. For example, at an angle of attack of 20° flow separation occurs severely, when the steady CFJ is adopted; however, the airflow becomes fully attached on the upper airfoil, when the rectangular pulsed CFJ is employed. As a result, the lift corresponding to the rectangular wave is higher than that of the sinusoidal wave. The results also indicate that the lower duty cycle and pulse frequency can lead to the higher lift but with more power consumption.

Size-controlled flow synthesis of nanoporous particles are of considerable interest for future industrial applications, however, is facing challenges due to lack of in-situ method for size-characterization in fluidic environment. We present that ultraviolet-visible (UV–vis) absorption spectroscopy can be integrated into a flow-synthesis system which was produced by femtosecond laser micromachining. The shift of the absorption peak position of the ex-situ and in-situ UV–vis spectra correlates to variation of size of porous metal-organic frameworks crystals. ZIF-67 crystals with a size in the range from 200 nm to 1025 nm are fabricated with the assistance of tri-ethylamine under monitoring of in-situ UV–vis spectra. The ZIF-67 crystals are converted into nanoporous carbons particles with controlled sizes. These materials show size-dependent performance in Na-ion battery and size-independent performance in metal/H2O seawater battery.

In this paper, a universal approach toward constructing a new bilayer device architecture, a few-nanometer-thick third-component layer on a bulk-heterojunction (BHJ) binary blend layer, has been demonstrated in two different state-of-the-art organic photovoltaic (OPV) systems. Through a careful selection of a third component, the power conversion efficiency (PCE) of the device based on PM6/Y6/layered PTQ10 layered third-component structure was 16.8%, being higher than those of corresponding devices incorporating the PM6/Y6/PTQ10 BHJ ternary blend (16.1%) and the PM6/Y6 BHJ binary blend (15.5%). Also, the device featuring PM7/Y1-4F/layered PTQ10 layered third-component structure gave a PCE of 15.2%, which is higher than the PCEs of the devices incorporating the PM7/Y1-4F/PTQ10 BHJ ternary blend and the PM7/Y1-4F BHJ binary blend (14.2 and 14.0%, respectively). These enhancements in PCE based on layered third-component structure can be attributed to improvements in the charge separation and charge collection abilities. This simple concept of the layered third-component structure appears to have great promise for achieving high-performance OPVs.

The outstanding properties of perovskites have attracted huge attention in optoelectronic applications. However, the current study mainly focuses on small-area single-layer perovskite films. Surfac...

Light absorption is a common phenomenon in nature, but accurate and quantitative absorption measurement at the nanoscale remains challenging especially in the application of widefield imaging. Here...

Grafting of organic groups on the surface of metal-oxide clusters greatly enhances the Li+ ion capacity. Triply organo-substituted polyoxometalates (RN-POMs) display an excellent Li+ ion capacity (...

Controllable crystal phases (α-, β-, γ- and δ-) of MnO2 materials were developed via tuning hydrothermal conditions and investigated in toluene catalytic combustion. Extensive characterization techniques such as XRD, BET, SEM, TEM, H2-TPR and XPS were employed for analyzing the structure-performance relationship between physicochemical properties, such as specific surface area, vacancy/lattice oxygen and their mobility, reduction property and catalytic activity. Results indicated that the degradation activity of MnO2 catalyst greatly hinges on materials intrinsic properties, namely the vacancy oxygen generation, lattice oxygen content and their reduction behaviors. α-MnO2 exhibited the best catalytic activity (0.24 μmol/min @ 240 °C) among the obtained MnO2 materials; however, its cycle stability was inferior to that of δ-MnO2 catalyst owing to the different moderating effect of potassium ions remained within the tunnels or mezzanines structure. In addition, δ-MnO2 showed an easiest reduction property among all the manganese oxides investigated. The findings will shed lights on designing of Mn-based catalysts with a higher VOCs combustion capacity.

A polymer-based hole-transporting layer (HTL) with a tunable work function and highest occupied molecular orbital (HOMO) position was demonstrated to effectively optimize the anode junctions of optoelectronic devices. Herein, the perfluorinated ionomer (PFI) was utilized to realize the synthesis of a well-dispersed poly(3,4-ethylene dioxythiophene) (PEDOT) colloid solution, which could be subsequently cast into an efficient HTL. According to the time-of-flight secondary-ion mass spectroscopy and ultraviolet photoelectron spectroscopy analysis, a uniform, interpenetrating PEDOT network with a deep-lying HOMO position could be obtained in the PEDOT:PFI layer. For solar cells, since a deep-lying HOMO position of the HTL was favorable for minimizing the hole injection barrier, a superior organic photovoltaic efficiency of 15.1% and a perovskite solar cell efficiency of 17.8% were achieved. As for organic photodetectors, a deep-lying HOMO position of the HTL was able to reduce the dark current density (JD) by blocking the leakage current under a reverse bias. Utilizing the PEDOT:PFI with an optimized PFI content, an extremely low JD of 6.2 nA cm−2 with an external quantum efficiency of 67% at 1000 nm wavelength was achieved, which sets a benchmark for the emerging near infrared sensing technologies.

As a half-reaction of electrolytic water-splitting for hydrogen generation, the oxygen evolution reaction (OER) is the major bottleneck due to the sluggish kinetics of the four-electron transfer reaction. Developing high-efficiency and cost-effective OER electrocatalysts is crucial to the advancement of water-splitting. Besides the conventional metal-based nanoparticle catalysts, constructing single-atom catalysts (SACs) on two-dimensional (2D) materials has become an important research direction in recent years. In this review, we summarize the recent strategies for the synthesis of SACs, the experimental and theoretical studies of 2D material-based SACs to enhance the OER performance, and the rational design principles of SACs toward the OER, as well as the challenges and future directions. A discussion is provided for a better understanding of the OER, to guide the optimization of electrocatalysts, and for possible future candidates of SACs.

Cu2ZnSnS4 (CZTS) has demonstrated excellent performance as an anode material for lithium-ion batteries. However, the repeated lithiation and delithiation create a cracking pattern and lead to island formation in the thin-film electrode, resulting in a capacity fading over cycling in lithium-ion batteries (LIB's). In order to control this crack behaviour, we introduce carbon into CZTS thin-films by a hydrothermal method to form CZTS@C composite. CZTS@C significantly reduced the crack pattern formation on the electrode surface as well as improved the conductivity of the CZTS@C electrode. At the early stages of lithiation and delithiation, the volume expansion and contraction of Li–CZTS@C create intra-granular cracking only at the surface level, and it offers a high capacity of about 785 mA h g−1 after 150 cycles at 1000 mA g−1 charging rate, excellent rate capability (942 mA h g−1, 678 mA h g−1 and 435 mA h g−1 at 500 mA g−1, 2000 mA g−1 and 5000 mA g−1), and superior cyclability (925 mA h g−1 even after 200 cycles at 500 mA g−1). The excellent electrochemical performance at high-current rates can be attributed to intra-granular cracking together with carbon coating that provides a short transportation length for both lithium ions and electrons. Moreover, the controlled cracking pattern formation in CZTS@C facilitates faster reaction kinetics, which open up a new solution for the development of high-power thin-film anodes for next-generation LIBs applications.

Effectively converting CO2 into fuels and value-added chemicals remains a major challenge in catalysis, especially under mild conditions. In this study, we report a one-step plasma-enabled catalytic process for CO2 hydrogenation to C2+ hydrocarbons operated at low temperature and atmospheric pressure in a dielectric barrier discharge (DBD) packed-bed reactor. Plasma without catalyst produces mainly CO (over 80% selectivity), while CH4 becomes the main product when plasma is coupled with the alumina-supported Co catalyst. Interestingly, by simply changing the catalyst-bed configuration within the plasma discharge zone, more C2+ hydrocarbons are selectively produced. High C2+ hydrocarbons selectivity of 46% at ca. 74% CO2 conversion is achieved when operated at the furnace temperature of 25 °C and 10 W DBD plasma. The possible origin of C2+ formation and the significance of catalyst-bed configuration are discussed.

Gels prepared from low-molecular-weight gelators (LMWGs) represent versatile soft materials. Self-assembly of LMWGs forms nanofibers and above critical gelation concentrations, the entanglement of which leads to self-supporting gels. Owing to the dynamic properties of the self-assembly process, stimuli-responsive LMWGs have prospered in the last decade. In addition, incorporating multiple LMWGs into one system brings the opportunity to achieve sophisticated designs and functions. This review covers recent advances in the field of supramolecular gels, from stimuli-responsive gelators to multicomponent systems that are self-sorting and/or co-assembling.

Searching for high-activity, stable and low-cost catalysts toward oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) are of significant importance to the development of renewable energy technologies. By using the computational screening method based on the density functional theory (DFT), we have systematically studied a wide range of transition metal (TM) atoms doped a defective BC3 monolayer (B atom vacancy VB and C atom vacancy VC), denoted as TM@VB and TM@VC (TM = Mn, Fe, Co, Ni, Cu, Ru, Rh, Pd, Ir and Pt), as efficient single atom catalysts for OER and ORR. The calculated results show that all the considered TM atoms can tightly bind with the defective BC3 monolayers to prevent the atomically dispersed atoms from clustering. The interaction strength between intermediates (HO*, O* and HOO*) and catalyst govern the catalytic activities of OER and ORR, which has a direct correlation with the d-band center (ed) of the TM active site that can be tuned by adjusting TM atoms with various d electron numbers. For TM@VB catalysts, it was found that the best catalyst for OER is Co@VB with an overpotential ηOER of 0.43 V, followed by Rh@VB (ηOER = 0.49 V), while for ORR, Rh@VB exhibits the lowest overpotential ηORR of 0.40 V, followed by Pd@VB (ηORR = 0.45 V). For TM@VC catalysts, the best catalyst for OER is Ni@VC (ηOER = 0.47 V), followed by Pt@VC (ηOER = 0.53 V), and for ORR, Pd@VC exhibits the highest activity with ηORR of 0.45 V. The results suggest that the high activity of the newly predicted well dispersed Rh@VB SAC is comparable to that of noble metal oxide benchmark catalysts for both OER and ORR. Importantly, Rh@VB may remain stable against dissolution at pH = 0 condition. The high energy barrier prevents the isolated Rh atom from clustering and ab initio molecule dynamic simulation (AIMD) result suggests that Rh@VB can remain stable under 300 K, indicating its kinetic stability. Our findings highlight a novel family of efficient and stable SAC based on carbon material, which offer a useful guideline to screen the metal active site for catalyst designation.

Organic phase change materials (PCMs) play an important role in heat energy storage, but they are also limited by the leakage problem in the process of phase change. Herein, shape-stabilized composite PCMs (ssPCMs) are successfully obtained by impregnating paraffin (PA) into the polymethylsilsesquioxane (PMSQ) aerogels. Due to abundant porosity, light weight, inherent superhydrophobic of PMSQ aerogels, lipophilic PA can be loaded into aerogels with a high PCMs loading rate up to 876% without alkylation process. Under the action of aerogel pores, PA in ssPCMs has high degree of crystallinity. The three-dimensional network structure of aerogels can effectively support the melting PA, and there is almost no leakage problem under the strong capillary force and surface tension. The ssPCMs show high latent heat in the range of 117.2 J/g to 122.9 J/g and excellent thermal stability and recyclability where their latent heat nearly remains 97% after 50 times of melting-crystallization cycles. More interestingly, when the temperature reaches above the melting point of PA, the ssPCMs changes from white to translucent. Thus, the synthesized ssPCMs exhibit considerable potential in energy storage applications, temperature intelligent response, thermal regulation.

A hybrid electrocatalyst composed of NiCoP and MoxC has been prepared via the two-step calcination method. Microscopic analysis demonstrates that the heterojunctions formed by the NiCoP and MoxC are disordered and stacked irregularly. The NiCoP/MoxC heterojunctions are produced during the second calcination treatment. The synergistic effects promote water adsorption and dissociation, and H2 desorption. More active sites are provided by the irregular structure, the NiCoP/MoxC-X catalyst are imparted excellent electrocatalytic activity toward hydrogen evolution reaction (HER) activity. To sustain a current density of 10.0 mA/cm2, the overpotentials of NiCoP/MoxC-15 are 79.0 and 116.0 mV while the Tafel slopes are 52.3 and 57.4 mV/dec for the electrocatalyst operated in 1.0 M KOH and 0.50 M H2SO4, respectively. When operating in alkaline medium for 10.0 h at an overpotential of 123.0 mV, the retaining catalytic activity of this material reaches 93.0%.

We investigate the effects of gas-liquid ratio (GLR) on the spray and atomization process of a liquid-centered swirl coaxial injector using the coupled level-set and volume of fluid (CLSVOF) method. The flow field, gas-liquid interaction, and breakup of liquid film during adaptive mesh refinement are evaluated and analyzed. The results show that, with the increase of GLR, the atomization process becomes dominated successively by the instability of the liquid film, strong gas-liquid interaction and spray self-pulsation. Moreover, more droplets are found near the center of the spray cone while the spray angle decreases. The inclined surface waves on the liquid film may be formed owing to Rayleigh-Taylor instability. When GLR is relatively large, holes are produced and break up on the liquid film due to the high velocity of the gas. Then, the gas-liquid interaction pushes small droplets towards the center of the spray cone, while large droplets and ligaments distribute on the periphery of the spray. With even larger GLRs, self-pulsation occurs, which is found to determine the flow structures inside the spray cone and to generate, shed and dissipate vortices periodically. Furthermore, when self-pulsation occurs, the near-field pressure and mass flow rate fluctuations increase rapidly.

A series of NiCexAl (x = 0.1, 0.3, 0.5, 0.7 and 0.9) mixed metal oxides catalysts was synthesized through decomposing the corresponding layered double hydroxides (LDH) precursors, and then characterized by TG, XRD, N2 adsorption/desorption, XPS, H2-TPR, H2-TPD etc. techniques. The results showed that the introduction of Ce could efficiently restrict the agglomeration of Ni species. The generated Ni–Ce–O solid solution could create the oxygen vacancies and enhance the oxygen mobility which further improved the properties of active sites including Ni dispersion and surface area, and suppressed coke deposition. The Ni2+ species was reduced by Ce3+ under the reaction conditions to give the metallic Ni as active sites in catalyzing steam reforming of glycerol for the production of hydrogen. The best catalytic performance was obtained over the sample NiCe0.7Al which exhibited the better Ni dispersion and larger surface, and lower quantity of deposited coke by establishing the correlations. The reaction was more selective to hydrogen thanks to the enhancement of water gas shift reaction and suppression of CO methanation reaction.

Glass-ceramics for low-temperature co-fired-ceramic 5G wireless devices exhibit excellent microwave properties. However, silver diffusion and interdiffusion of the electrode decreases the high-frequency conductivity. In this work, the inhibition of the silver diffusion mechanism in CaO-MgO-SiO2 glass-ceramics was investigated. Specimens without SiO2 were found to exhibit both Ag diffusion and Zn, Mg, and Ca interdiffusion. In contrast, samples with SiO2 show much less diffusion and a Ag6O2 phase at the diffusive boundary layer, indicating that the SiO2 addition inhibits Ag diffusion and interdiffusion. Elemental mapping indicated the presence of a concentration gradient-reaction between the SiO2 particles and the glass-ceramic. This reaction enhances the glass viscosity and inhibits Ag diffusion and interdiffusion. SiO2-added glass-ceramics co-fired with an Ag electrode show improved 5G-patch-antenna microwave characteristics, with an enhanced conductivity at ~8.2 GHz and a return loss of S11 = -23 dB at ~28.3 GHz.

It has been widely accepted that the viscosity of alloy melts increases monotonically with temperature decreasing after exceeding the liquidus temperature. However, a distinct viscosity-drop has been observed in several alloy melts in our previous works. To further understand this dynamic anomaly, we investigated the viscosity of CuZrAl and CuZrTiNi melts by gradually changing the compositions of alloy systems. The results suggest that when the amounts of doping elements (Al, Ti, Ni) become large enough, this abnormal viscosity-drop disappears. For CuZr binary alloys, the anomaly exists when the composition of Zr ranges between 27.3–66.7%, which nearly corresponds to the available content of Zr in CuZr bulk metallic glasses. By conducting molecular dynamics simulation, the mechanism that four icosahedron-like clusters with high fragility evolves with temperature in Cu62Zr38 melts has been recognized. In contrast to general aggregation or growth of clusters during cooling process, an unexpected tendency that more segregations are formed among these clusters and the clusters become further dispersed in liquids has been discovered around 1400 K; meanwhile, the viscosity-drop in our experiments begins simultaneously at this temperature. Below 1300 K, these icosahedron-like clusters aggregate abruptly again. Experimental results from differential scanning calorimeter (DSC) and high-resolution transmission electron microscope (HRTEM) further approve the influence of these fragile icosahedron-like clusters on crystallization processes. This finding uncovers the same structural origin that underlies both the formation of bulk metallic glasses and the dynamic anomaly in melts, and demonstrates the dominant role of fragile icosahedron-like clusters in the feature of liquid dynamics.

The bimetallic MNi/CNTs (M Co, Cu and Fe) catalysts with controlled metal distribution were prepared by a two-step impregnation method. The catalysts were characterized by N2 adsorption/desorption, XRD, XPS, TPR, HAADF-STEM, TEM and TG to study the porous structure, changes in crystalline phases during the reaction, surface chemical state, reducibility, the element distribution, sintering of metal particles and the deposited coke for the calcined and/or spent catalysts. The results showed that the Ni oxide was successfully introduced into the cave and the other one was dispersed on the external wall of CNTs. The addition of the secondary metals had significant influences on the reducibility, resulting in the quite different surface properties which was directly linked to the products distribution in glycerol reforming reaction. The sample CoNi/CNTs performed better in both anti-sintering and coke resistance, and over which the product was more selective to hydrogen by enhancing the water gas shift reaction.

NiZrAl layered double hydroxides (LDH) precursors were synthesized by co-precipitation and homogeneous precipitation processes. The introduction of hydrothermal treatment into crystallization showed its significant influences on structure of LDH as well as mixed-metal oxides after thermal decomposition. The characterization results showed that the catalysts prepared by hydrothermal synthesis involved bigger pore diameter of ca. 13.5 nm and wider pore size distribution of 2–60 nm, and hydrothermal treatment was helpful to enhance the reduction of NiO species weakly interacted with support and to enhance the interaction among the metal oxides. Although the Ni dispersion, the surface area as well as the ability of anti-sintering were evidently improved, the ability of coke resistance decreased by 2 times for samples prepared by co-precipitation and by nearly 10 times for the ones prepared by homogeneous precipitation due to the enlarged pores. The maximum value of conversion to gaseous products (96.5%) and minimum deposited coke (36 mgc/gcat.) were achieved on NiZrAl-u sample.

Lithium-rich layered oxides have the advantages of high specific capacity (> 250 mAh g−1) and high energy density, which make them highly competitive in the lithium-ion cathode material market. However, low efficiency, poor cycle stability, and poor rate performance severely constrained their development. In this paper, the spherical lithium-rich Li1.2Mn0.54Ni0.13Co0.13O2 compound was rapidly synthesized by microwave hydrothermal method, and the microwave hydrothermal time was optimized. The samples were characterized and analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy (Raman), and X-ray photoelectron spectroscopy (XPS). The prepared lithium-rich compound is porous spherical secondary particles, of which the size distributed between 2.5 and 3.5 μm, which makes materials have larger specific surface area and active potential and promotes the improvement of electrochemical kinetics. The results of 100 charge-discharge cycles show that the microwave hydrothermal 40-min cathode has good stability, and the capacity retention rate can reach 91.4%. Furthermore, it can still provide a discharge capacity of 160.5 mAh g−1 at a current density of 5 C.

Ag/g-C3N4 plasmonic photocatalysts with porous structure (Ag/PCN) were successfully synthesized via a thermal exfoliation strategy and photo-reduction method. Owing to the combined merits of porous structure and surface plasmon resonance effect of silver nanoparticles, the Ag/PCN catalysts exhibited excellent photocatalytic performance for the degradation of antibiotic agents. With the optimal Ag loading, the Ag/PCN-2 catalyst exhibited the optimal catalytic activity for TC degradation under visible light, which shows about 11.8 times enhancement in the photocatalytic removal efficiency as compared to pure g-C3N4, respectively. This phenomenon can be attributed to the increased specific surface area, broadened visible light absorption and improved charge separation. The radical quenching results confirmed that h+ and O2− radicals were the major active species during removal of TC. The degradation of TC is increased with the increment of Ag/PCN-2 catalysts, and the optimum catalyst was found to be 1.67 g/L. The hindering effect of selected of anions (Cl−, CO3−, H2PO4−) was found to follow the order H2PO4− > CO3− > Cl−. Ag/PCN-2 sample also possessed high stability after six cycles of reuses. Furthermore, the possible degradation pathways of TC and photocatalytic mechanism over Ag/PCN-2 were proposed in detail.

Silicon photonics have attracted significant interest because of their potential in integrated photonics components and all-dielectric meta-optics elements. One major challenge is to achieve active control via strong photon–photon interactions, i.e. optical nonlinearity, which is intrinsically weak in silicon. To boost the nonlinear response, practical applications rely on resonant structures such as microring resonators or photonic crystals. Nevertheless, their typical footprints are larger than 10 μm. Here, we show that 100 nm silicon nano-resonators exhibit a giant photothermal nonlinearity, yielding 90% reversible and repeatable modulation from linear scattering response at low excitation intensities. The equivalent nonlinear index is five-orders larger compared with bulk, based on Mie resonance enhanced absorption and high-efficiency heating in thermally isolated nanostructures. Furthermore, the nanoscale thermal relaxation time reaches nanosecond. This large and fast nonlinearity leads to potential applications for GHz all-optical control at the nanoscale and super-resolution imaging of silicon., Resonant structures are a promising method to enhance the nonlinear response of Si, however they are typically larger than 10 μm. Here, the authors present Si nano-resonators that amplify photothermal nonlinearity, resulting in reversible and repeatable modulation.

In this paper, the common diseases about bridge deck pavement of the completed highway in Heilongjiang province have been made practical investigation and analyze why these diseases happen. It also combines the climate features in north cold areas，from the way of using High quality modified asphalt，reducing the catalytic point temperature of pitch to improve the low temperature anti-crack property, using high strength coarse and fine aggregate，adjusting gradation of mixture aggregate and the ratio of oil to stone to improve temperature and water stability and durability for Concrete pavement project of Nao Li river bridge connected Jian San river with Hu Lin highway .From trabecular bending test、Freeze-thaw splitting test、Rutting test and Immersion Marshall test，that compares different influence research on pavement performance of bridge with Bitumen concrete bridge deck which have different polyester fiber content .The experimental result indicates the proportion of polyester fiber can clearly ameliorate the temperature stability、hypothermia anti-cracking performance and water stability of Asphalt .And within a certain range of polyester fiber content，various road performances will be improved with the increasing of polyester fiber content，and on this basis，the optimum polyester fiber content is raised.

Nonlinear optical microscopy can obtain three-dimensionally resolved images within a specimen by exploiting the nonlinear light–matter interaction between the excitation light and sample. However, ...

Herein, core-twisted tetrachloroperylenediimides (ClPDIs) were introduced as new efficient electron-transporting materials (ETMs) to replace the commonly used fullerene acceptor PC61 BM in inverted planar perovskite solar cells (PSCs). ClPDI showed a low-lying lowest unoccupied molecular orbital (LUMO) energy level of -3.95 eV, which was compatible with the conduction band of CH3 NH3 PbI3-x Clx (-3.90 eV). In addition, the role of the length of the alkyl side chain at the imide position of ClPDI in modulating the molecular solubility, aggregation capacity for charge-transport properties, surface hydrophobicity, and PSC performance was investigated. The device based on ClPDI-C4 (ClPDI with n-butyl side chains) as ETM achieved a maximum power conversion efficiency (PCE) of 17.3 % under standard AM 1.5G illumination, which iwas very competitive with that of the reference device employing PC61 BM/C60 (PCE=17.2 %) as ETM. Moreover, the devices with ClPDIs as ETMs exhibited better device stability than that with PC61 BM/C60 . This work highlights the great potential of ClPDI derivatives as low-cost (≈2.0 USD g-1 ) and effective ETMs to obtain efficient solution-processed inverted PSCs. This class of ClPDI derivatives is expected further promote the performance and stability of PSCs after extended investigation.

A well-crystalline two-dimensional (2D) perovskite material, Ca2Nan–3NbnO3n+1– (CNNO–) nanosheets, derived from the Dion–Jacobson phase has the potential to generate hydrogen through photoelectroch...

In this work, a series of mesoporous silica supported nickel or nickel-palladium catalysts were synthesized and performed in dry reforming of methane (DRM) reaction for producing syngas. Compared with the monometallic catalyst, the Ni–Pd bimetallic catalysts, especially synthesized by the OA-assisted route, exhibited promising yields of H2 and CO in the catalytic DRM reaction, achieved at 63% and 69% over NiPd-SP-OA bimetallic catalyst at the reaction temperature of 700 °C, respectively. TEM image results confirmed that no obvious sintering phenomenon happened on spent NiPd-SP-OA bimetallic catalyst within 1550 min time-on-stream reaction. Based on the results of XRD, XPS and H2-TPR, it could be known that the superior catalytic performance on NiPd-SP-OA catalyst were main ascribed to the smaller-sized Ni nanoparticles with a uniform metal dispersion and a larger fraction of exposed active sites (Ni0).

A series of mesoporous CoxM3-xAlOy (M Ni, Mn) catalysts have been obtained by calcination of layered double hydroxide (LDH) precursors prepared by the microwave method, the catalysts exhibited high activity for methane catalytic combustion. By changing the preparation method and type of metal salt introduced (Ni and Mn), it is effective for controlling the structure properties and reducibility of catalyst as well as the catalytic performance for the methane catalytic combustion. The Co2Ni1AlOy catalyst exhibited higher catalytic performance and the temperature required to achieve a methane conversion of 90% (T90) was about 473 °C, this temperature was 40 °C lower than that on the NiO-IWI/Co3AlOy sample. The enhanced catalytic activity was correlated with higher surface area, better redox property, higher ratio of surface Co3+/Co2+ species and surface absorbed oxygen and lattice oxygen (Oads/Olatt) derived from the synergistic effect over Co2Ni1AlOy catalyst. Therefore, the microwave method provided an effective path to develop the efficient combustion catalyst for higher performance.

Na3V2(PO4)2F3 is a prospective cathode material for sodium ion batteries (SIBs) because of its high theoretical capacity. Nevertheless, its low electronic conductivity leads to poor cycling and rate performance, hindering its practical application. In this work, ultrafine-Na3V2(PO4)2F3 nanocrystals less than 20 nm embedded in porous carbon nanospheres are fabricated via a microwave-assisted glycerol-mediated hydrothermal process followed by annealing. Microwave irradiation is shown to be critical for the formation of homogenous ultrafine nanostructure. The product exhibits a charge/discharge capacity of 106 mAh g−1 at 0.5 C after 100 cycles with a retention of approximate 100% as cathode material for SIBs.

Bimetallic catalysts NiCo/CNTs with distribution-controlled Ni and Co species were prepared by modified impregnation method with the assistance of dimethylbenzene and characterized by XRD, N2 adsor...

A large amount of heat is generated during the friction of joint surfaces, which has a significant influence on the contact characteristics of surfaces, causing deformation or failure of key components. A two-dimensional friction-thermal structure coupling contact model of cylinder/plane was established in ABAQUS. The effects of roughness under different fractal parameters, tangential load amplitude and cycle number on the temperature rise distribution of a contact surface under normal cyclic loading were studied. The results show that with the increase of roughness and tangential load amplitude, the area of thermal effect becomes more obvious and the temperature rise of the contact surface increases. It is also found that the heat affected zone is mainly distributed near the surface of the contact area with a high-temperature field generated, while the temperature rise amplitude decreases gradually along the depth direction. In addition, the contact surface nodes have a similar temperature rise distribution process and the farther away from the contact center ( x = 0.3 mm), the smaller the temperature rise, which is consistent with the simulation results of the published literature. For the same tangential load amplitude, the surface temperature rise amplitude under the normal cyclic load is lower than that of the normal constant load. The temperature rise of the surface increases with the increase of the number of fretting cycles.

A series of CuCo2O4 composite spinels with an interconnected meso-macroporous nanosheet morphology were synthesized using the hydrothermal method and subsequent calcination treatment to activate peroxymonosulfate (PMS) for benzophenone-4 (BP-4) degradation. As-prepared CuCo2O4 composite spinels, especially CuCo-H3 prepared by adding cetyltrimethylammonium bromide, showed superior reactivity for PMS activation. In a typical reaction, BP-4 (10.0 mg/L) was almost completely degraded in 15 min by the activation of PMS (200.0 mg/L) using CuCo-H3 (100.0 mg/L), with only 9.2 μg/L cobalt leaching detected. Even after being used six times, the performance was not influenced by the lower leaching of ions and surface-absorbed intermediates. The possible interface mechanism of PMS activation by CuCo-H3 was proposed, wherein a unique interconnected meso-macroporous nanosheet structure, strong interactions between copper and cobalt, and cycling of Co(II)/Co(III) and Cu(I)/Cu(II) effectively facilitated PMS activation to generate SO4•- and •OH, which contributed to BP-4 degradation. Furthermore, combined with intermediates detected by liquid chromatography quadrupole time-of-flight mass spectrometry and density functional theory calculation results, the degradation pathway of BP-4 involving hydroxylation and C-C bond cleavage was proposed.

Glass ceramics have demonstrated excellent millimeter-wave dielectric properties for low-temperature-co-fired-ceramic (LTCC) devices applied in the 5G communication. This study highlights silver (Ag)-diffusion mechanism and millimeter-wave dielectric properties of CaO-MgO-SiO2 glass ceramics co-fired with Ag electrode near nucleation temperatures. Ag diffusion and elemental inter-diffusion occur during the endothermic-exothermic process near nucleation temperatures (~820 °C), where Ag diffused into the glass-ceramic matrix and resided around the diopside-phase grain boundaries while other metal elements (Zn, Mg, and Al) diffused into the Ag layer. Oxygen ions can flee from the glass-ceramic network above glass transition temperature during the endothermic process and react with the Ag ions to form the Ag-O bonds. The low dielectric dissipation in the millimeter-wave range remains after Ag diffused into the matrix. However, conductivity of Ag-electrode layer decreases at a GHz frequency due to the inter-diffusion elements with lower electric conductivities.

Photon capturing is an essential step for the operation of a solar cell. In this article, we develop a bifacial solar cell with characteristics of double-side photon collection, transparent appearance, mechanical flexibility, and facile processing. The whole device was fully fabricated by a spin-coating technique. A power conversion efficiency (PCE) as high as 2.46% has been achieved using the most prominent photoactive material, poly(3-hexylthiophene):(6, 6)-phenyl C61 butyric acid methyl ester (P3HT:PCBM). The bifacial solar cell can retain 92% of its original PCE after 350 cyclic bending cycles at bending radii of 7.4 mm. In addition to the mechanical instability of the device, photochemical degradation is partially involved in the device operation. We believe that our device with its promising mechanical, physical, and processing features can serve as an essential power element to be integrated with other technologies for the next-generation self-powered technology.

As the problem of asphalt concrete bridge deck pavement is becoming more and more serious, how to improve its road performance has become the focus of the study. As the lack of shear strength and bond strength between layers, flaking, raveling and other diseases were occurred on steel bridge deck asphalt pavement. This paper combines the common damages of bridge deck and asphalt concrete pavement in cold area of northeast region, focuses on the analysis of the cause of asphalt concrete pavement damage causes, puts forward preventive measures and recommendations, and present the bridge deck pavement structure in cold area combined with the engineering practice. The research results can effectively guide the construction of bridge deck pavement.

Spherical core–shell structures have been widely investigated in recent years, and they can be used for various applications, such as drug delivery, biological labeling, and batteries. Although many methods have been developed to prepare core–shell structures, it is still a great challenge to fabricate core–shell structures in the nanoscale with well-controlled morphologies and sizes. In this work, we present a simple method to fabricate core–shell polymer nanospheres consisting of polystyrene (PS) cores and poly(methyl methacrylate) (PMMA) shells. The nanostructures are prepared by a solution-based template wetting method. After the nanopores of anodic aluminum oxide (AAO) templates are wetted sequentially by PS/PMMA blend solutions and water, the core–shell nanostructures can be formed. The formation process is related to the Rayleigh-instability-type transformation. Selective removal techniques are also used to confirm the morphologies of the core–shell nanostructures.

Since the days of Cajal, optical microscopy has been a vital tool for physiology, and neuroscientists have accumulated significant amount of information on structures and functions of isolated neurons. However, to understand the emergent properties of a brain, functional observation of complicated neuronal networks is necessary, leading to the request of volumetric imaging with high speed, deep penetration, and sub-cellular resolution. In this talk, I report our recent advances on pushing the speed of volumetric imaging, and its applications on Drosophila and mouse brains.

There is a lack of understanding of the spray characteristics of gas-centered swirl coaxial (GCSC) injectors during self-pulsation occurs. Therefore, the self-pulsation of a GCSC injector was investigated experimentally in this study. Experiments were conducted at atmospheric pressure with filtered water and dried air supplied through a propellant feed system. A back-lighting high-speed photography technique was used to capture unsteady spray features. A laser-based particle size analyzer (LPSA) was used to measure the size of the droplets in the spray. The effects of recess and gas-liquid ratio on spray self-pulsation were analyzed. It was found that the recess of the injector strongly determines the spray pattern. When spray self-pulsation occurs without recess, both the center and periphery of the spray oscillate. With an increase in the mass flow rate of the gas, the boundary between the center and the periphery of the spray becomes more noticeable. Meanwhile, small droplets in the spray center oscillate, with the periphery of the spray being characterized by a periodic “shoulder.” Under the same operating conditions but with a small recess (2 mm), the spray adheres to the injector faceplate. With a larger recess (7 mm), when spray self-pulsation occurs, the spray periodically forms “shoulder” and “neck,” similar to the behavior of self-pulsation in a liquid-centered coaxial injector. Therefore, it can be concluded that spray self-pulsation enhances atomization at the center of the spray to a certain extent. However, atomization becomes worse in the periphery with an oscillating spray.

In recent years, the primary greenhouse gas (carbon dioxide) has caused a series of severe issues, such as global warming, climate change, etc. Therefore, CCU, CCS and CCUS technologies have been employed to reduce CO₂ emissions. Through our developed "chemical vapor deposition integrated process (CVD-IP)" using carbon dioxide as the carbon source, CO₂ could be catalytically activated and converted to high-value carbon nanotubes. In this work, methane and carbon dioxide has been applied to synthesize CNTs respectively to compare the difference between conventional CH4 CVD and CO₂ CVD-IP technology using Ni-Mo bimetallic catalysts. In the conventional CH4 CVD technology, the carbon productivity and the thermal stability of CNTs could be improved by changing the Mo content of the catalyst, the better catalytic performance 4% Mo catalyst is selected as model catalyst to apply to CO₂ CVD-IP technology. Moreover, when the weak oxidant CO₂ is the only carbon source in the CVD-IP technology, the carbon yield is 22% and the carbon productivity is 1.98 g/gcat. TG curves and Raman spectroscopy display that the CNTs with better thermal stability and higher degree of graphitization are achieved. TEM confirms that the fewer wall numbers and defects of CNTs are obtained. These characterizations suggest that the high quality CNTs could be achieved by CO₂ CVD-IP technology.