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The effects of support materials on catalytic performance were investigated in catalytic removal of toluene. And the Mn–Ce binary oxides as active components were supported on ZrO2, SiO2, γ-Al2O3 and TiO2 support materials. Many techniques, including X-ray diffraction (XRD), Brunauer–Emmett–Teller method (BET), X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR) and NH3-temperature-programmed desorption (NH3-TPD), were used to characterize physicochemical properties. Among the different catalysts, the MnCe/ZrO2 catalyst with the lowest specific surface area (39.7 m2/g) shows the best catalytic activity. In terms of toluene conversion, the activity order is as follows: MnCe/ZrO2 > MnCe/TiO2 ≈ MnCe/SiO2 > MnCe/Al2O3. The better performance of MnCe/ZrO2 should be attributed to the low-temperature reducibility, and abundant surface species (Mn4+ and lattice oxygen). And XPS and TPR results reveal that more surface abundant Mn and Ce elements generate good interaction in MnCe/ZrO2. The weak interaction between metal oxide and support also boosts the dispersion and complete reduction of MnCe oxides at low temperature. In addition, the in-situ DRIFTS results clarify that the carbonate species are main intermediates in MnCe/ZrO2 sample during surface reaction process.

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.

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.

A series of CuZn/xCe-ZnAl2O4 catalysts (CZ/xCe-ZAO) with different contents of Ce doping (x = 0, 3, 5, and 7 wt%) were prepared by precipitation. The samples were applied for the hydrogenation production from methanol decomposition. Ce doping was found to effectively improve the reaction activity of the catalysts. CZ/5Ce-ZAO exhibits 100.0% methanol conversion and selectivity to hydrogenation of 98.9% at 300 °C (WHSV = 1.5 h−1), which is superior to those of the comparison catalysts. Moreover, the TOF for CZ/5Ce-ZAO increased by 54.7% compared with the pristine sample without Ce doping. In addition, CZ/5Ce-ZAO showed significantly improved stability compared with that of the un-doped catalysts. The obtained catalysts were systematically characterized by N2 sorption, XRD, H2-TPR, XPS, TEM, N2O-TPD, TG–DTA. The results suggested that stronger metal-support interaction (SMSI) existed in the Ce doped samples increased the dispersion of Cu species, which was responsible for the outstanding catalytic performance. Besides, such SMSI was also helpful for inhibiting the sintering of the copper species during the reaction and enhancing stability. CZ/5Ce-ZnAl2O4 shows significantly improved stability compared with the undoped and commercial catalysts.

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.

The geometric effects of Coanda trailing edges on the aerodynamic performance of an airfoil are numerically evaluated for a range of different freestream Mach numbers and momentum coefficients. A Circulation control (CC) airfoil with a circular trailing edge (ACTE) proves to have better control effectiveness at low subsonic freestream speeds (Mach = 0.1). A CC airfoil having an elliptic trailing edge (AETE) outperforms the ACTE at high subsonic flow conditions. The occurrence of C μ-stall for the AETE is greatly postponed, and meanwhile the maximum net lift coefficient increment achieved for the AETE (Δ C L = 0.51) is slightly higher than that of the ACTE (Δ C L = 0.50) at Mach 0.6. Compared to the ACTE, the AETE is found to have better control consistency at different operating velocities and better control stability when the Coanda jet is supersonic. Through careful consideration of the aerodynamic performance and the control effects, the most appropriate axial ratio for an AETE ellipse is within the interval from 1.5 to 2. Finally, the flow field instability phenomenon and the jet detachment induced by the supersonic Coanda jet are investigated. A self-sustained shock-wave instability phenomenon without jet detachment is first observed in this paper.

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.

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...

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.

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.

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.

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.

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.

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.

A hydrolysis-resistant polymer bearing new quasi-choline phosphate (quasi-CP) structures as side groups, poly(2-methacryloyloxyethyl choline methylphosphonate) (PMCPm), was designed and synthesized...

Interfacial electron transfer within the electrode is crucial for various electrocatalytic reactions. Herein, we demonstrated that in-situ grown Cu2O on Cu foam as a scaffold to load active ingredients could lower the interfacial contact resistance and promote the electron transfer in oxygen evolution reaction. Meanwhile, the Cu2O/Cu (CCF) facilitates to load active components due to higher surface area resulting from its irregular scattered structure. As a demonstration, Ni–Fe doubles layered hydroxide (NiFe-LDH) coated carbon nanotube spheroidal particles (CNS@NiFe) was anchored by a drop-casting route to assemble CNS@NiFe/CCF hybrid electrodes with the CCF as scaffolds. The CNS@NiFe/CCF electrode afforded an ultralow overpotential of 248 mV at 10 mA cm−2 and a small Tafel slope of 32.9 mV dec−1 with an excellent stability. Schematic illustration of CNS@NiFe/CCF architecture.

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.

Emerging and resurging mosquito-borne flaviviruses are an important public health challenge. The increased prevalence of dengue virus (DENV) infection has had a significant socioeconomic impact on epidemic countries. The recent outbreak of Zika virus (ZIKV) has created an international public health emergency because ZIKV infection has been linked to congenital defects and Guillain-Barre syndrome. To develop potentially prophylactic antiviral drugs for combating these acute infectious diseases, we have targeted the host calcium/calmodulin-dependent kinase II (CaMKII) for inhibition. By using CaMKII structure-guided inhibitor design, we generated four families of benzenesulfonamide (BSA) derivatives for SAR analysis. Among these substances, N-(4-cycloheptyl-4-oxobutyl)-4-methoxy-N-phenylbenzenesulfonamide (9) showed superior properties as a lead CaMKII inhibitor and antiviral agent. BSA 9 inhibited CaMKII activity with an IC50 value of 0.79 μM and displayed EC50 values of 1.52 μM and 1.91 μM against DENV and ZIKV infections of human neuronal BE(2)C cells, respectively. Notably, 9 significantly reduced the viremia level and increased animal survival time in mouse-challenge models.

Mesoporous CeMnOx composite oxides catalysts were prepared by surfactant-assisted co-precipitation method and used for the catalytic oxidation of toluene. The effect of different cerium precursors [Ce(NO3)3 and (NH4)2Ce(NO3)6] on catalyst structure, surface properties and toluene combustion activities of mesoporous CeMnOx catalysts were investigated. The Ce(III)MnOx catalyst prepared from Ce(NO3)3 precursor shows higher catalytic activity, with a 90% conversion temperature of 240 °C, which is better than the Ce(IV)MnOx catalyst derived from (NH4)2Ce(NO3)6] precursor. On the basis of characterizations, it reveals that abundant surface content of Mn4+, better redox behavior and larger concentration of surface active oxygen species are responsible for the excellent catalytic performance.

Rationally designing efficient, low-cost and stable catalysts toward the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR) is of significant importance to the development of renewable energy technologies. In this work, we have systematically investigated a series of potentially efficient and stable single late transition metal atom doped phthalocyanines (TM@Pcs, TM = Mn, Fe, Co, Ni, Cu, Ru, Rh, Pd, Ir and Pt) as single-atom catalysts (SACs) for applications toward the OER and ORR through a computational screening approach. Our calculations indicate that TM atoms can tightly bind with Pc monolayers with high diffusion energy barriers to prevent the isolated atoms from clustering. The interaction strength between intermediates and TM@Pc governs the catalytic activities for the OER and ORR. Among all the considered TM@Pc catalysts, Ir@Pc and Rh@Pc were found to be efficient OER electrocatalysts with overpotentials ηOER of 0.41 and 0.44 V, respectively, and for the ORR, Rh@Pc exhibits the lowest overpotential ηORR of 0.44 V followed by Ir@Pc (0.55 V), suggesting that Rh@Pc is an efficient bifunctional catalyst for both the OER and ORR. Moreover, it is worth noting that the Rh@Pc catalyst can remain stable against dissolution under the pH = 0 condition. Ab initio molecular dynamic calculations suggest that Rh@Pc could remain stable at 300 K. Our findings highlight a novel family of two-dimensional (2D) materials as efficient and stable SACs and offer a new strategy for catalyst design.

Technological implementation of organolead trihalide perovskite (OTP) photovoltaics requires suppression of the surface ionic defects and grain boundaries of OTP films. These surface ionic defects have a detrimental effect on the power conversion efficiency (PCE), are notorious for introducing hysteresis into the current density–voltage (J–V) characteristics, and decrease the stability of perovskite solar cells (PSCs). Here, we report the use of core/shell quantum dots (QDs) as passivation layers on the OTP surfaces to decrease the trap density and, simultaneously, stabilize the OTP chemical structure and extend the charge carrier lifetime. Density functional theory (DFT) calculations indicated that the OTP surface defects and grain boundaries were effectively suppressed by the presence of the CdSe/ZnS QDs. We attribute the lower trap density of the OTP to the Se2− anions from the CdSe/ZnS passivation layer, inducing van der Waals interactions between the organic and inorganic components of the framework. For PSCs featuring CdSe/ZnS QD passivation, the PCE reached close to 20% with diminishing hysteresis of the J–V characteristics and fill factor (FF) of 81.44%. Moreover, the PSCs incorporating the CdSe/ZnS QD passivation layer exhibited long-term stability, retaining 75 and 80% of their initial performance after 2400 and 720 h, respectively. This facile interfacial strategy appears highly applicable for preparing high-performance durable OTP-based high optoelectronic devices.

Ionic liquids (ILs) show great promise to endow electric double-layer capacitors (EDLCs) with high energy density; however, their operation in practical deep-cold environments has been severely plagued by two major problems, namely (i) poor compatibility between the electrode material and the ILs and (ii) the ease of freezing of ILs. Here, we show that the combination of a nitrogen-doped mesopore-dominated hierarchical carbon (NMHC) electrode with plentiful ion-accessible adsorption sites (specific surface area and pore volume of 2637.4 m2 g−1 and 1.679 cm3 g−1) and anti-freezing EMIBF4–GBL electrolyte with high ion-conductivity (2.3 S cm−1 at −50 °C) can address this issue. Specifically, “H-bond breakage” in EMIBF4 ILs was proposed for the first time to understand the anti-freezing mechanism, as evidenced by Raman spectroscopy, 1H NMR spectroscopy, and density functional theory calculations. As a result, the combination of NMHC electrode with EMIBF4–GBL electrolyte enabled an impressive specific energy of 61 W h kg−1 at −50 °C, which was 10.7 times larger than that of commercial YP50. This work showed excellent electrode–electrolyte synergy and provides a new understanding of IL-based electrolytes for low-temperature energy storage.

Over the past decade, intensive research efforts have been directed toward the field of organic–inorganic hybrid perovskites, with dramatic progress made in both the photovoltaic performance and device stability. Therefore, it has become the fastest growing photovoltaic research area. Perovskite materials use low-cost earth-abundant elements and can be solution-processed; furthermore, the technology is compatible with large-scale roll-to-roll manufacturing. Recently, the successful demonstration of the photovoltaic performance of perovskites reaching that of the commercialized monosilicon photovoltaic technology combined with the significantly improved stability has made scaling-up the perovskite PV technology to become a new research area, which is the topic of this review. First, the fundamental background knowledge of classical nucleation and crystal growth from a solution is summarized along with its application in perovskite film evolution. We then discuss the common perovskite PV device architectures and perovskite layer deposition methods, followed by summarizing scalable solution approaches with recent progress and related challenges for the scaling-up process. Upon the introduction of the current in-depth understanding of perovskite nucleation and crystal growth, external strategies (including both physical and chemical approaches) controlling the perovskite film formation are reviewed in diverse scalable manufacturing methods. Overall, aiming at overcoming the challenges of transferring from laboratory research, we provide an overview of achieving high-performance perovskite solar cells by using scalable fabrication methods via precise nucleation and crystal growth control during the perovskite film formation process.

This research studied the spatiotemporal variation in methane in the middle to upper troposphere during the Wenchuan earthquake (12 May 2008) using AIRS retrieval data and discussed the methane anomaly mechanism. Three indices were proposed and used for analysis. Our results show that the methane concentration increased significantly in 2008, with an average increase of 5.12 × 10 - 8 , compared to the average increase of 1.18 × 10 - 8 in the previous 5 years. The absolute local index of change of the environment (ALICE) and differential value (diff) indices can be used to identify methane concentration anomalies. The two indices showed that the methane concentration distribution before and after the earthquake broke the distribution features of the background field. As the earthquake approached, areas of high methane concentration gradually converged towards the west side of the epicenter from both ends of the Longmenshan fault zone. Moreover, a large anomalous area was centered at the epicenter 8 d before the earthquake occurred, and a trend of strengthening, weakening and strengthening appeared over time. The gradient index showed that the vertical direction obviously increased before the main earthquake and that the value was positive. The gradient value is negative during coseismic or post-seismic events. The gradient index reflects the gas emission characteristics to some extent. We also determined that the methane release was connected with the deep crust–mantle stress state, as well as micro-fracture generation and expansion. However, due to the lack of any technical means to accurately identify the source and content of methane in the atmosphere before the earthquake, an in-depth discussion has not been conducted, and further studies on this issue may be needed.

The northern Carpathian Basin has important geological, paleoenvironmental, and archeological records that are key to our understanding of the first modern human occupation of Europe. However, the nature and timing of hominin settlements in the region during the Late Pleistocene remain poorly understood. New fieldwork at Seňa I, Slovakia, has identified the only known stratified open-air Aurignacian site in the region and assigned the assemblage to at least 33.5 ± 2.4 ka ago through infrared-stimulated luminescence dating. Additionally, new archeological and geoscientific data are presented. This paper discusses the Seňa I findings in the context of the regional archeological record and shows how they contribute to the establishment of clear time constraints for the Aurignacian in eastern central Europe.

An OH−-slow-release strategy was established to controllably tune the (α- and β-) phase of nickel cobalt binary hydroxide in the presence of ammonium chloride. Ammonium chloride is added to the ionic solution to regulate the pH of the solution and slow down the release of OH−, effectively regulating the phase, nanostructure, interlayer spacing, surface area, thickness, and the performance of binary Ni Co hydroxide. The ion-slow-release mechanism is conducive to the formation of α-phase with larger interlayer spacing and thinner flakes rather than β-phase. Attributed to the enlarged interlayer spacing, thinner nanosheets, and more exposed active sites, the resultant α-phase hydroxides (NCNS-5.2), displayed much lower over potential of 285 mV with respect to the dense-stacked β-phase hydroxides (362 mV) for OER at 10 mA/cm2. It also exhibited high specific capacitance of 1474.2 F/g, when tested at 0.5 A/g within a voltage range of 0–0.45 V vs. Hg/HgO. This composite was also stable for water oxidation reaction and supercapacitor. The proof-of-concept of using controlled-release agent may provide suggestive insights for the material innovation and a variety of applications.

Nonlinear nanoplasmonics is a largely unexplored research area that paves the way for many exciting applications, such as nanolasers, nanoantennas, and nanomodulators. In the field of nonlinear nanoplasmonics, it is highly desirable to characterize the nonlinearity of the optical absorption and scattering of single nanostructures. Currently, the common method to quantify optical nonlinearity is the z-scan technique, which yields real and imaginary parts of the permittivity by moving a thin sample with a laser beam. However, z-scan typically works with thin films, and thus acquires nonlinear responses from ensembles of nanostructures, not from single ones. In this work, we present an x-scan technique that is based on a confocal laser scanning microscope equipped with forward and backward detectors. The two-channel detection offers the simultaneous quantification for the nonlinear behavior of scattering, absorption and total attenuation by a single nanostructure. At low excitation intensities, both scattering and absorption responses are linear, thus confirming the linearity of the detection system. At high excitation intensities, we found that the nonlinear response can be derived directly from the point spread function of the x-scan images. Exceptionally large nonlinearities of both scattering and absorption are unraveled simultaneously for the first time. The present study not only provides a novel method for characterizing nonlinearity of a single nanostructure, but also reports surprisingly large plasmonic nonlinearities.

The era of big data in healthcare is here, and this era will significantly improve medicine and especially oncology. However, traditional machine learning algorithms need to be promoted to solve such large-scale realworld problems due to a large amount of data that needs to be analyzed and the difficulty in solving problems with nonconvex nonlinear settings. We aim to minimize the composite of a smooth nonlinear function and a block-separable nonconvex function on a large number of block variables with inequality constraints. We propose a novel parallel first-order optimization method, called asynchronous block coordinate descent with time perturbation (ATP), which adopts a time perturbation technique that escapes from saddle points and sub-optimal local points. The details of the proposed method are presented with analyses of convergence and iteration complexity properties. Experiments conducted on real-world machine learning problems validate the efficacy of our proposed method. The experimental results demonstrate that time perturbation enables ATP to escape from saddle points and sub-optimal points, providing a promising way to handle nonconvex optimization problems with inequality constraints employing asynchronous block coordinate descent. The asynchronous parallel implementation on shared memory multi-core platforms indicates that the proposed algorithm, ATP, has strong scalability.

The thermal deposition of lead iodide (PbI2) results in the changes in the contact surface of a poly (3,4-ethylenedioxythiophene) poly (styrene sulfonate) (PEDOT:PSS) layer of solar cells (SCs). The changed contact surface of PEDOT:PSS layer after the thermal deposition of PbI2 remains stable after PbI2 is converted into perovskite and leaves the degraded perovskite/PEDOT:PSS interface. The degraded perovskite/pristine PEDOT:PSS interface leads to a low power conversion efficiency (η%) of SCs at 3.84%. The properties of the contact surface of the PEDOT:PSS layer during the thermal deposition of PbI2 can be retained by treating PEDOT:PSS with dimethyl sulfoxide (DMSO) and maintain the perovskite/PEDOT:PSS interface in good condition after PbI2 is converted. Perovskite SCs with DMSO-treated PEDOT:PSS substantially improves η% from 3.84% to 9.58%.

In this paper, we demonstrate a unique multifunctional separator prepared by sputtering a thin layer of graphite on top of a commercial polypropylene–polyethylene separator. This modified separator...

We have developed a one-pot synthesis of bio-carbon nanowires from the natural product sodium alginate at low temperature, without using any catalyst, for anticoagulation applications. Sodium alginate is carbonized and sulfated/sulfonated in situ by solid state heating of a mixture of sodium alginate and ammonium sulfite. By regulating the heating temperature and the ratio of ammonium sulfite to sodium alginate, we modulated the degree of sulfation/sulfonation and carbonization, as well as the morphology of the carbon nanomaterials. The core-shell sulfated/sulfonated bio-carbon nanowires (CNWsAlg@SOx) made by the reaction of a mixture of ammonium sulfite and sodium alginate with a mass ratio of 5 (ammonium sulfite to sodium alginate) at 165 °C for 3 h, exhibit strong inhibition of thrombin activity due to their ultrahigh binding affinity towards it (dissociation constant (Kd) = 8.7 × 10−11 M). The possible formation mechanism of the carbon nanowires has been proposed. The thrombin-clotting time delay caused by CNWsAlg@SOx is ∼ 170 times longer than that caused by sodium alginate. Hemolysis and cytotoxicity assays demonstrated the high biocompatibility of CNWsAlg@SOx. Furthermore, the thromboelastography of whole-blood coagulation and rat-tail bleeding assays further reveal that CNWsAlg@SOx have a much stronger anticoagulation activity than sodium alginate and naturally sulfated polysaccharides (e.g., fucoidan). Our results suggest that the low-temperature prepared, cost-effective, and highly biocompatible CNWsAlg@SOx show great potential as an efficient anticoagulant for the prevention and treatment of diseases associated with thrombosis.

Hybrid lead halide perovskites continue to attract interest for use in optoelectronic devices such as solar cells and light-emitting diodes. Although challenging, the replacement of toxic lead in these systems is an active field of research. Recently, the use of trivalent metal cations (Bi3+ and Sb3+) that form defect perovskites A3B2X9 has received great attention for the development of solar cells, but their light-emissive properties have not previously been studied. Herein, an all-inorganic antimony-based two-dimensional perovskite, Cs3Sb2I9, was synthesized using the solution process. Vapor-anion-exchange method was employed to change the structural composition from Cs3Sb2I9 to Cs3Sb2Br9 or Cs3Sb2Cl9 by treating CsI/SbI3 spin-coated films with SbBr3 or SbCl3, respectively. This novel method facilitates the fabrication of Cs3Sb2Br9 or Cs3Sb2Cl9 through solution processing without the need of using poorly soluble precursors (e.g., CsCl and CsBr). We go on to demonstrate electroluminescence from a device employing Cs3Sb2I9 emitter sandwiched between ITO/PEDOT:PSS and TPBi/LiF/Al as the hole and electron injection electrodes, respectively. A visible-infrared radiance of 0.012 W·Sr-1·m-2 was measured at 6 V when Cs3Sb2I9 was the active emitter layer. These proof-of-principle devices suggest a viable path toward low-dimensional, lead-free A3B2X9 perovskite optoelectronics.

CeO2 nanorods supported nickel catalysts were prepared by wetness impregnation method, using nickel nitrate and nickel chloride as nickel sources. The dried catalyst precursors were decomposed either by thermal calcination or glow discharge plasma technique. The effects of precursor decomposition methods and nickel sources on the catalytic performance of glycerol steam reforming were then investigated. Characterization and catalytic results showed that glow discharge plasma treatment instead of thermal calcination enhanced the nickel dispersion, improved the Ni-Ce interaction and led to the formation of Ni-O-Ce composite, which could both enhance the H2 selectivity and restrain the coke deposition during reaction. Thus, no deactivation was observed on the two plasma treated catalysts throughout the tests. Nickel source may influence both rate of particle sintering and carbonaceous deposition during reaction; fast nickel sintering but slower coke deposition was found on the catalysts prepared from nickel chloride, and coke deposition was more detrimental to active sites decrease than nickel sintering.

Mercury ion (Hg2+) sensor based on bottom gate top contact organic thin film transistor (OTFT) was fabricated. The OTFT channel area was functionalized with pyrene that contain thiol group, which has strong binding affinity toward Hg2+ ion. The OTFT sensor exhibited a charge mobility of 0.28 cm2 V−1 s−1, a threshold voltage of −22.3 V and on-to-off ratio 103. The sensor shows high selectivity to Hg2+ ion over other two valence metal ions. OTFT sensor exhibited high sensitivity to Hg2+ ion, indicated by increasing of drain current after exposed to different concentration of Hg2+ ion ranging from 1 mM to 0.01 μM. Moreover, the OTFT sensor capability for practical application was also demonstrated by sensing the present of 25 μM of Hg2+ ion in tap, drinking and seawater samples.

Metal oxide carrier transporting layers have been investigated widely in organic/inorganic lead halide perovskite solar cells (PSCs). Tin oxide (SnO2) is a promising alternative to the titanium dioxide commonly used in the electron transporting layer (ETL), due to its tunable carrier concentration, high electron mobility, amenability to low-temperature annealing processing, and large energy bandgap. In this study, a facile method was developed for the preparation of a room-temperature-processed SnO2 electron transporting material that provided a high-quality ETL, leading to PSCs displaying high power conversion efficiency (PCE) and stability. A novel physical ball milling method was first employed to prepare chemically pure ground SnO2 nanoparticles (G-SnO2), and a sol–gel process was used to prepare a compact SnO2 (C-SnO2) layer. The effects of various types of ETLs (C-SnO2, G-SnO2, composite G-SnO2/C-SnO2) on the performance of the PSCs are investigated. The composite SnO2 nanostructure formed a robust ETL having efficient carrier transport properties; accordingly, carrier recombination between the ETL and mixed perovskite was inhibited. PSCs incorporating C-SnO2, G-SnO2, and G-SnO2/C-SnO2 as ETLs provided PCEs of 16.46, 17.92, and 21.09%, respectively. In addition to their high efficiency, the devices featuring the composite SnO2 (G-SnO2/C-SnO2) nanostructures possessed excellent long-term stability—they maintained 89% (with encapsulation) and 83% (without encapsulation) of their initial PCEs after 105 days (>2500 h) and 60 days (>1400 h), respectively, when stored under dry ambient air (20 ± 5 RH %).