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In preparation for an experiment with a laser-generated intense proton beam at the Laser Fusion Research Center at Mianyang to investigate the 11B(p,α)2α reaction, we performed a measurement at very low proton energy between 140 keV and 172 keV using the high-voltage platform at the Institute of Modern Physics, Lanzhou. The aim of the experiment was to test the ability to use CR-39 track detectors for cross-section measurements and to remeasure the cross-section of this reaction close to the first resonance using the thick target approach. We obtained the cross-section σ = 45.6 ± 12.5 mb near 156 keV. Our result confirms the feasibility of CR-39 type track detector for nuclear reaction measurement also in low-energy regions.

A novel Ag3VO4/CoWO4 p–n heterostructure was designed and prepared by an in situ growth method. The physicochemical properties were characterized by multiple techniques, and the photocatalytic performances in Cr(vi) reduction and TC degradation were also evaluated under visible-light irradiation.

To enable accurate system-level electrostatic discharge (ESD) simulation, this article applies statistical learning to obtain I/O port models of the victim integrated circuits (ICs). A quasi-static I–V model derived using kernel regression can capture the circuit board dependency of the behavior observed at the I/O pin, regardless if there is snapback. The non-parametric kernel model can be reduced to a system-specific parametric model, which has smaller requirements for computing time and memory. In some cases, transient system-level ESD simulation may require the IC model to replicate the dynamic behavior of the nonlinear circuit. A recurrent neural network is demonstrated to be a suitable model in such cases. This article provides a detailed RNN training flow for IC pin modeling, and presents a Verilog-A implementation of the RNN for use with Simulation Program with Integrated Circuit Emphasis (SPICE)-type simulators.

The title coordination polymer, {[Co2(C12H7NO8)(H2O)6]·5H2O} n , was crystallized at room temperature from an aqueous solution of 2-aminodiacetic terephthalic acid (H4adtp) and cobalt(II) nitrate. The asymmetric unit consists of one adtp4− ligand, one and two half CoII ions, six water ligands coordinated to CoII ions and five uncoordinated water molecules. Two of the cobalt cations lie on centres of inversion and are coordinated in octahedral O2(OH2)4 environments, whereas the other adopts a slightly distorted octahedral NO3(OH2)2 environment. The crystal structure contains parallel stacked, one-dimensional zigzag chains, {[Co2(C12H7NO8)(H2O)6]} n , which assemble into a three-dimensional supramolecular architecture via networks of hydrogen bonds involving the coordinated and free water molecules. One-dimensional `water tapes' are formed, containing alternating six-membered and twelve-membered rings of water molecules, together with water pentamers, in which a central uncoordinated water molecule is hydrogen bonded to two coordinated and two free water molecules in a tetrahedral arrangement.

Controlling spin behavior via external stimuli is a key route to develop molecular spintronics devices. Photons, temperature, pressure, chemicals, and electric field are the possible stimuli. Herei...

Micropollutants (MPs) are widely occurring in surface water all over the world with extremely low concentrations, and their treatment requires high energy consumption and efficiency. In this study, a large-sized planar photocatalytic reactive ceramic membrane (PRCM) was prepared using the facile dip-coating method with nitrogen-doped TiO2 (N-TiO2-CM) for the purification of tetracycline hydrochloride (TC) as a model MP. The N-TiO2 nanoparticles and the as-prepared N-TiO2-CM were characterized by SEM/EDS, TEM, XPS, UV–Vis DRS, and FT-IR. A fixed bed reactor integrated N-TiO2-CM, and visible LED light was fabricated for the new PRCM water treatment system for the removal of TC with a comprehensive consideration of the degradation rate and permeate flux. The SEM/EDS results indicated that the N-TiO2 was uniformly and tightly loaded onto the flat CM, and the pure water flux could reach over 2000 L/(m2 × h) under a trans-membrane pressure (TMP) of −92 kPa. The fixed bed PRCM water treatment system is extremely suited for MP purification, and the removal efficiency of TC was as high as 92% with 270 min even though its initial concentration was as low as 20 mg/L. The degradation rate and permeate flux of N-TiO2-CM was 2.57 and 2.30 times as high as that of the CM, indicating its good self-cleaning characteristics. The quenching experiments illustrated that the reactive radicals involved in the PRCM process, •OH and •O2−, were responsible for TC degradation. This research also provides a utilization proposal for a scale-up N-TiO2-CM system for water and wastewater treatment.

Microstructure and mechanical properties of ADC12 composites reinforced with graphene nanoplates (GNPs) prepared by high-intensity ultrasonic assisted casting were investigated. The results indicated that high-intensity ultrasound can promote the uniform distribution of GNPs in the melt, resulting in refining the α(Al) phase and Si phase. The optimal addition of GNPs was 0.9 wt.%, and the optimal ultrasonic time was 12 min. The tensile strength, the yield strength and the hardness of the composite produced under the optimal parameters were 256.8 MPa, 210.6 MPa and HV 126.0, respectively, which increased by 30.5%, 42.7%, and 34.8% compared with those of the matrix, respectively. After adding the GNPs, the fracture mechanism gradually turned from a brittle fracture to a ductile fracture. The good interface and distribution allowed GNPs to play the role in fine grain strengthening, dislocation strengthening and load transfer strengthening effectively.

Lithium metal represents an ultimate anode material of lithium batteries for its high energy density. However, its large negative redox potential and reactive nature can trigger electrolyte decomposition and dendrite formation, causing unstable cycling and short circuit of batteries. Herein, we engineer a resilient solid electrolyte interphase on the Li anode by compositing the battery separator with organosulfur compounds and inorganic salts from garlic. These compounds take part in battery reactions to suppress dendrite growth through reversible electrochemistry and attenuate ionic concentration gradient. When the Li anode and the separator are paired with the LiFePO4 cathode, one obtains a battery delivering long-term cycling stability of 3000 cycles, a rate capacity of 100 mAh g-1 at 10 C (2.5 mA cm-2), a Coulombic efficiency of 99.9%, and a low battery polarization. Additionally, with high-loading 20 mg cm-2 LiFePO4 cathodes, an areal capacity of 3.4 mAh cm-2 is achieved at 0.3 C (1 mA cm-2).

BaLu2−xF8:xLn3+ crystals have been synthesized via a one-step hydrothermal route without any surfactants. X-ray diffraction (XRD), scanning electron microscopy (SEM), and down-shift/up-conversion photoluminescence spectroscopy were used to characterize the samples. Pure monoclinic BaLu2F8 crystals were obtained at pH = 7 with NaBF4 as a fluoride source. Doping 0.06 mmol Ln3+ ions from Ho3+ to La3+ and doping Yb3+ ions from 0.1 to 0.4 mmol both have caused dramatic changes to the product's morphology from prismatic microrods of about 10 μm to particles of about 3 μm aggregated by flakes. The differences in the phase, size and shape of the final products were greatly related to the fluoride source and pH values, which have been studied in detail. In addition, surfactants also affected the phase and morphology of the BaLu2F8 crystals. Multicolor down-shift emission was achieved in the BaLu1.94F8:0.06Ln3+ (Ln = Sm, Eu, Tb, Dy, Er and Tm) crystals under UV lamp excitation at 365 nm, and multicolor UC luminescence has been achieved in BaLu2F8:Yb3+,Ln3+ (Ln = Er, Tm, Ho) systems. When the Yb3+–Er3+ ions are co-doped into the host, the mechanism for the red emission (4F9/2 → 4I15/2) retains the tri-photon process like the single-doped Er3+ ion, but the mechanism for the green emission (2H11/2/4S3/2 → 4I15/2) is a two-photon process. Furthermore, the UC luminescence mechanism for the co-doped Yb3+–Ho3+ pairs is also a tri-photon process in the BaLu2F8 matrix. The as-prepared BaLu2F8:Ln3+ phosphors have potential applications in the fields of light emitting devices, three-dimensional displays and backlights.

The continuous pursuit of miniaturization in the electronics and optoelectronics industry demands all device components with smaller size and higher performance, in which thin metal film is one heart material as conductive electrodes. However, conventional metal films are typically polycrystalline with random domain orientations and various grain boundaries, which greatly degrade their mechanical, thermal and electrical properties. Hence, it is highly demanded to produce single-crystal metal films with epitaxy in an appealing route. Traditional epitaxy on non-metal single-crystal substrates has difficulty in exfoliating away due to the formation of chemical bonds. Newly developed epitaxy on single-crystal graphene enables the easy exfoliation of epilayers but the annealing temperature must be high (typical 500–1,000 °C and out of the tolerant range of integrated circuit technology) due to the relative weak interfacial interactions. Here we demonstrate the facile production of 6-inch transferable high-quality Pd(111) films on single-crystal hybrid graphene/Cu(111) substrate with CMOS-compatible annealing temperature of 150 °C only. The interfacial interaction between Pd and hybrid graphene/Cu(111) substrate is strong enough to enable the low-temperature epitaxy of Pd(111) films and weak enough to facilitate the easy film release from substrate. The obtained Pd(111) films possess superior properties to polycrystalline ones with ~ 0.25 eV higher work function and almost half sheet resistance. This technique is proved to be applicable to other metals, such as Au and Ag. As the single-crystal graphene/Cu(111) substrates are obtained from industrial Cu foils and accessible in meter scale, our work will promote the massive applications of large-area high-quality metal films in the development of next-generation electronic and optoelectronic devices.

The main objective of this paper is to reveal the mechanism of enhanced excitation light absorption in nano-pores structure BaMgAl10O17:Eu2+ (BAM) phosphor by optical analysis. The optical refractive index of the BAM was calculated from the reflectance spectra by Kramers–Kronig dispersion relation. And based on the effective medium theory, the anisotropic optical properties of porous BAM layer and its relations of absorption enhancement with porosity and thickness were investigated. A finite element simulation model was used for study the influence of pores size on optical properties. All the numerically evaluated results were match the experimental data.

Two-dimensional (2D) magnetic materials provide an ideal platform for the application in spintronic devices due to their unique spin states in nanometer scale. However, recent research on the exfoliated monolayer magnetic materials suffers from the instability in ambient atmosphere, which needs extraordinary protection. Hence the controllable synthesis of 2D magnetic materials with good quality and stability should be addressed. Here we report for the first time the van der Waals (vdW) epitaxial growth of one-unit-cell-thick air-stable ferrimagnet Cr2S3 semiconductor via a facile chemical vapor deposition method. Single crystal Cr2S3 with the domain size reaching to 200 μm is achieved. Most importantly, we observe the as grown Cr2S3 with a Neel temperature (TN) of up to 120 K and a maximum saturation magnetic momentum of up to 65 μemu. As the temperature decreases, the samples show a transition from soft magnet to hard magnet with the highest coercivity of 1000 Oe. The one-unit-cell-thick Cr2S3 devices sh...

KYb3F10:Ln3+ (Ln = Er, Ho, Tb, Gd, Eu, Sm, Ce and La) micro/nanocrystals with abundant morphologies were synthesized via a one-step hydrothermal route without employing any surfactants. Furthermore, the homogeneous and well-defined KYb3F10 crystals with truncated tetragonal bipyramidal, nanoparticle, nanospherical, microtubular and rugby ball shapes were achieved by manipulating the different environments of crystal growth, such as increasing the concentration of F−, adjusting the pH, using different fluorine sources and adding trisodium citrate. XRD, SEM, EDS and PL as well as lifetime analysis were used to characterize the products. The obtained KYb3F10:Ln3+ products showed bright emission colors red (Eu3+) and green (Tb3+), respectively. It has been found that larger crystal shapes/sizes can greatly enhance their luminescence properties and lifetimes due to their high crystallinity and few defects on the crystal surface. The as-synthesized KYb3F10:Eu3+/Tb3+ products might be potentially applied in multicolor lighting and displays.

A series of BaMgF4:Ce3+/Tb3+/Eu3+ phosphors were successfully prepared via a facile hydrothermal process. X-ray diffraction (XRD), energy dispersive spectrometry (EDS), scanning electron microscopy (SEM), n-UV–UV-vis photoluminescence (PL) and fluorescence decays were employed to investigate the structure, composition, morphology, luminescence properties and energy transfer processes. The as-prepared BaMgF4 phosphors exhibit a rod-like morphology and the size of the product can be effectively regulated by changing the amount of NH4F in the original solution. Under n-UV–UV light excitation, the Ce3+, Tb3+ and Eu3+ singly-doped BaMgF4 phosphors all show good characteristic luminescence; the Ce3+–Tb3+ and Tb3+–Eu3+ co-doped BaMgF4 phosphors both show tunable emission colors from blue (green) to green (orange-red) because of the energy transfer of Ce3+ → Tb3+ and Tb3+ → Eu3+, respectively. Moreover, the efficient energy transfer from Ce3+ (Tb3+) to Tb3+ (Eu3+) ions in the co-doped samples was confirmed by investigating the excitation/emission spectra and decay lifetimes. The results indicate that the phosphors may be potentially used as single-component multi-color phosphors for white light-emitting diodes.

In this paper, a multi-functional frequency selective polarization converter (FSPC) based on the substrate integrated waveguide cavities (SIWC) is presented. The proposed structure is based on a circular shape SIWC with orthogonal rectangular slots on the top/bottom layer of each unit cell. The neighboring SIWC are connected to each other by metalized vias which formed a shared diamond shape cavity. Two cross shape slots serve as additional input and output channel for the shared SIW cavity. The novel design introduces more functions to the device. When the device acts as a frequency selective surface, it provide two transmission window around 8.52 and 13 GHz. It can also realize cross-polarization conversion between TM and TE polarized waves from 15.87 to 17.01 GHz as well as narrowband polarization conversion around 10.33 GHz. The working mechanism of proposed design has been explained through the analysis of the surface current distribution. In order to verify the performance of the design, a prototype was manufactured and measured, the simulated and measured results are highly consistent with each other.

Hole transporting layer (HTL) plays an important role in device stability and charge transport for inverted perovskite solar cells (PSCs). Here, a novel HTL consisted of mesoporous NiO nanosheet (NS) was fabricated via simple hydrothermal method. The contract region of HTL/perovskite was increased by using the mesoporous NiO NS network structure, resulting in the good interface contract and rapid charge transfer. Therefore, the corresponding devices exhibit an optimal power conversion efficiency of >12%, with hysteresis-less. Besides, the developed PSCs still maintain 75% efficiency after 500 h, implying its good stability. In a word, this mesoporous NiO NS structure can be a promising candidate for HTL of inverted PSCs.

One-dimensional (1D) TiO2 nanofibrous film with good morphology and electrical characteristics was prepared by electrospinning technique. And then perovskite solar cells (PSCs) were fabricated based on 2-μm-thick mesoporous TiO2 nanofibrous film under ambient conditions even with a high humidity condition more than 40%. The devices show high power conversion efficiency (PCE) due to high porosity that is beneficial to the loading of CH3NH3PbI3 perovskite layer. This high-porosity 1D TiO2 nanofibrous film also acts as a protection layer which can enhance the moisture stability of CH3NH3PbI3. As a result, conversion efficiency of 11.6% and short-circuit current density (Jsc) of 17.3 mA were achieved under 100 mW cm−2 AM 1.5 G solar illumination. These two values are both higher than those of zero-dimensional (0D) TiO2 nanoparticulate film-based devices.

In recent years, reconfigurable metasurfaces have become research hotspots since they can manipulate electromagnetic waves dynamically and flexibly. The realisation of cost-effective and energy-efficient wireless communications via reconfigurable intelligent surfaces (RISs) is attractive in various application scenerios. In this work, a + 45 ∘ -polarized dual-band reconfigurable metasurface with beam steering ability is proposed to combat signal attenuation in wireless communications. By varying the bias voltages of the integrated varactors in the specially designed meta-atom, 0 and π phase responses have been excited around both 2.4 and 5.8 GHz. Taking advantage of this unique feature, we proposed a one-bit coding RIS device which provides dual-band application. To validate the proposed concepts, a reconfigurable metasurface composed of 16 × 16 elements was fabricated and measured. The measurement results agree well with the simulation, so the proposed prototype is a promising candidate for future intelligent communications.

Two fenclorim derivatives (compounds 6 and 7) were synthesized by linking active sub-structures using fenclorim as the lead compound. The chemical structures of the two compounds were confirmed by NMR spectroscopy, high resolution mass spectrometry, and X-ray diffraction analysis. Their fungicidal activity against six plant fungal strains was tested. Compounds 6 and 7 both crystallized in the monoclinic system, with a P21/c space group (a = 8.4842(6) &Aring, b = 24.457(2) &Aring, c = 8.9940(6) &Aring, V = 1855.0(2) &Aring, 3, Z = 4) and Cc space group (a = 10.2347(7) &Aring, b = 18.3224(10) &Aring, c = 7.2447(4) &Aring, V = 1357.50(14) &Aring, 3, Z = 4), respectively. The crystal structure of compound 6 was stabilized by C&ndash, H&middot, &middot, N and C&ndash, O hydrogen bonding interactions and N&ndash, N hydrogen bonds linked the neighboring molecules of compound 7 to form a three-dimensional framework. Compound 6 displayed the most excellent activity, which is much better than that of pyrimethanil against Botrytis cinerea in vivo. Additionally, compound 6 exhibited greater in vitro activity against Pseudoperonospora cubensis compared to that of pyrimethanil. Moreover, compound 7 exhibited strong fungicidal activity against Erysiphe cichoracearum at 50 mg/L in vitro, while pyrimethanil did not. Compounds 6 and 7 could be used as new pyrimidine fungicides in the future.

Hierarchical CuCo2O4@CoMoO4 nanowire/nanoplate hybrid nanostructures are successfully grown on Ni foam via simple methods involving hydrothermal and post-annealing treatment. The hybrid electrode exhibits a high areal capacity of 500 μAh/cm2 at 2 mA/cm2 and a good cycling stability with 84.1% retention over 2000 cycles at 20 mA/cm2. The assembled hybrid supercapacitor device based on CuCo2O4@CoMoO4 and activated carbon as the positive and negative electrodes achieves a maximum energy density of 49 Wh/kg at a power density of 318 W/kg, showing the great potential of this hybrid materials as advanced electrodes for energy storage devices.

Superhydrophobic silica nanoparticles were prepared by hydrothermal-assisted sol–gel process using a two-step synthesis route. Silica nanoparticles were obtained by hydrolysis and condensation of tetraethyl orthosilicate (TEOS). Hexadecyltrimethoxysilane (HDTMS) was added to allow the condensation reaction between HDTMS hydroxyl group and silica hydroxyl group, rendering silica particles hydrophobic. Silica nanoparticles had a HDTMS/TEOS molar ratio of 2:40 and exhibited good hydrophobic property with a high water contact angle of 156.1°. Water droplet rolled off the surface of silica powder owing to a low sliding angle of 3.6°. When hydrothermal time of TEOS decreased from 120 to 60 min, all silica powders gave rise to high water contact angles (≥154.8°) and low sliding angles (≤5.5°). However, silica powder became hydrophilic when HDTMS and TEOS were added to the precursor together. This facile preparation of superhydrophobic silica nanoparticles with short reaction time provided the advantages for potential application in industrial production.

The size enlargement of the c-growth-sector (c-GS) is a matter of great importance in fabricating high-performance YBa2Cu3O7−δ (Y123) bulks. Here, we report a novel construction of film-seed/buffer-layer/main-pellet, in which the 45°-aligned film-seed associated with a would-be [110]-sided buffer-layer was applied. The [110]-sided seed rapidly induced the crystallization of the buffer-layer with the (110) face, which prompted the second rapid growth on the main-pellet. Consequently, an Y123 bulk with sizable c-GS and high levitation force was achieved. The new seeding construction with the rapid growth nature of non-equilibrium face is encouraging for preparing other superconductor bulks in the Y123 family.

In this work, novel nanofibrous membranes with waterproof and breathable (W&B) performance were successfully fabricated by the combination of electrospinning and surface modification technology. This fibrous membranes consisted of polyurethane (PU), NaCl, and fluoroalkylsilane (FAS). Firstly, The fibrous construction and porous structure of fibrous membranes were regulated by tuning the NaCl concentrations in PU solutions. Then, the obtained PU/NaCl fibrous membranes were further modified with fluoroalkylsilane (FAS) to improve hydrophobic property. The synergistic effect of porous structure and hydrophobicity on waterproof and breathable performance was investigated. Furthermore, the mechanical property of fibrous membranes was deeply analysed on the basis of macromolecule orientation and adhesive structure. Benefiting from the optimized porous structure and hydrophobic modification, the resultant fibrous membranes exhibited excellent waterproof (hydrostatic pressure of 1261 Mbar), breathable (water vapor transmission (WVT) rate of 9.06 kg m−2 d−1 and air permeability of 4.8 mm s−1) performance, as well as high tensile strength (breakage stress of 10.4 MPa), suggesting a promising candidate for various applications, especially in protective clothing.

Highly flexible ZrO2/C nanofibers (NFs) coated with Ag nanoparticles (NPs) have been fabricated by a combination of electrospinning, carbonization and hydrothermal treatment. The obtained Ag@ZrO2/C NFs serve as low-cost counter electrodes (CEs) for flexible dye-sensitized solar cells (FDSSCs). A considerable power conversion efficiency of 4.77% is achieved, which is 27.9% higher than the η of ZrO2/C NFs CEs (3.73%) and reaches about 90% of that of Pt CE (5.26%). It can be ascribed to the fact that the introduction of Ag NPs provides a large number of accessible reaction sites for electrolyte ions to rapidly participate in the I3−/I− reaction. Moreover, the Ag NPs can produce synergistic effect with ZrO2/C NFs to further enhance transport capacity and electro-catalytic activity of the Ag@ZrO2/C film. Therefore, the considerable performance together with characteristics of simple preparation, low cost and flexibility suggests the Ag@ZrO2/C film can be promising candidate for the future generation of FDSSC.

Pellets of Mg and B mixture was buried by commercial MgB2 and one-step sintered at 800 °C, two-step sintered at 750 °C followed by 900 °C, and two-step sintered at 800 and 600 °C, respectively. Although an increasing amount of MgO was found in the burying sintered samples, the particles were considerably refined and embedded in the MgB2 grains, as the MgO is likely to be from the absorbed O2 on the commercial MgB2. Commercial MgB2 served as nucleation sites for newly formed MgB2 grains, which mostly generated at solid–solid reaction stage following Ostwald ripening mechanism. Apart from low crystallinity, such low-temperature synthesis of MgB2 induced defects including grain boundaries and second-phase particles as effective pinning centers. As a result, the critical current density is enhanced at high field in the burying sintered samples, in contrast with the one without burying.

NiO films were fabricated by reactive direct current magnetron sputtering on glass and alumina substrates for the application in energetic nano-multilayers. The structural and thermal properties of the films were investigated with the volume ratio of oxygen to argon ranging from 1:9 to 3:2, and the optimized ratio value is obtained as 1:3, which was confirmed by X-ray diffraction (XRD), atomic force microscopy and ultrafast measurement system. The effect of the film thickness, varying from 150 to 900 nm, on the structural properties was characterized by XRD and scanning electron microscopy (SEM). XRD analysis reveals that the (111) lattice plane is the preferred orientation. The intensities of preferential peaks and the grain sizes increase as the film thicknesses increase.

The structural, electrical, and magnetic properties of the double perovskite Ba2LuReO6 have been examined. It is an insulator whose temperature dependent conductivity is consistent with variable range hopping electrical transport. A transition to an antiferromagnet state with type I order occurs below TN = 31 K. High resolution time-of-flight neutron powder diffraction measurements show that it retains the cubic double perovskite structure down to 10 K. High intensity, low resolution neutron powder diffraction measurements confirm the antiferromagnetic order and indicate that cubic symmetry is still observed at 1.5 K. The small ordered moment of 0.34(4)μB per Re is comparable to estimates of moments on 5d2 ions in other antiferromagnetically ordered cubic double perovskites. Comparisons with related double perovskites containing 5d2 ions, such as Os6+ and Re5+, reveal that subtle changes in structure or electron configuration of the diamagnetic octahedral cations can have a large impact on the magnetic ground state, the size of the ordered moment, and the Neel temperature.

A bi-layer photoanode is successfully fabricated for dye-sensitized solar cells (DSSCs) composed of P25/TiO2 nanorod (P25/TNR) as the underlayer and TiO2 nanosheet spheres (TNSs) as the light-scattering layer. Notably, the P25-TNR provides multiple functions, including more dye loading, more efficient charge transport and a lower electron recombination rate for the photoanode. Besides, the unique structure of TNS can significantly improve the light-harvesting capacity, boosting the light-harvesting efficiency. Therefore, an enhanced short-circuit current and power conversion efficiency of 18.04 mA cm−2 and 5.99%, respectively, were achieved for the P25/TNR-TNS-based DSSC, which was better than that of the P25-TNS-based (15.17 mA cm−2, 5.36%) and bare TNS-based (11.43 mA cm−2, 4.14%) DSSCs. This indicates that this bi-layer structure effectively combines the advantages of the one-dimensional (1D) nanostructure and three-dimensional (3D) hierarchical structure. In short, this work demonstrates the possibility of fabricating desirable photoanodes for high-performance DSSCs by rational design of nanostructures and effective combination of multi-functional components.

Tetragonal AgLa(MoO4)2 microcrystals with novel discal hierarchical architectures were successfully synthesized via a one-step hydrothermal route. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and photoluminescence (PL) spectral analysis as well as decay lifetimes were employed to characterize the prepared products. It was found that various hierarchical architectures were obtained by altering the amount of MoO42−, pH values and surfactants, respectively. In particular, the pH value had a large influence not only on the morphology, but also on the size and crystallinity. The formation mechanism of discal hierarchical architectures was proposed on the basis of the self-assembly growth of nanosheets. The AgLa(MoO4)2 microcrystals exhibited excellent down/up-conversion (DC/UC) multicolor emissions after doping different Ln3+ ions. For DC luminescence, AgLa(MoO4)2:Ln3+ (Ln = Eu, Tb, Sm, Dy) exhibited characteristic red emission, green emission, orange emission and yellow emission, respectively. The energy transfer of MoO42− → Ln3+ (Ln = Tb, Sm, Dy) markedly enhanced the characteristic emissions of Tb3+, Sm3+ and Dy3+. For UC luminescence, AgLa(MoO4)2:Yb3+/Ln3+ (Ln = Er, Tm, Ho) exhibited intense green (2H11/2 → 4I5/2 of Er3+), blue (1G4 → 3H6 of Tm3+), yellow (5F5 → 5I8 of Ho3+) emissions, respectively. Therefore, the as-prepared AgLa(MoO4)2:Ln3+ microcrystals may have potential application to serve as fluorescent lamps, field emission display devices, sensors and biological imaging agents.

It remains highly challenging to deploy noble-metal-free technologies for commercial hydrogen evolution reaction (HER) catalytic application. A facile strategy is developed in this work to boost the HER activity on non-noble MoS2 catalyst by taking advantage of the platinum-like behavior of nitrogen doped carbon (C N) active sites for catalyzing the process from H+ to H atom. By doping trace amount of C N with the defect-rich MoS2 nanosheet catalyst, the HER activity is significantly improved with the onset HER overpotential reduced to 50 mV, close to the value observed for the platinum catalyst, and the operational overpotential at 10 mA/cm2 decreases by 65 mV. More importantly, with graphite as the counter electrode, stability of the catalyst is substantially improved. No activity decay is detected after 4000 cycles of cyclic voltammetry (CV) sweeping while the overpotential increment of the prisitine MoS2/C catalyst after 2000 cycles CV sweeping is high to ca. 15 mV.

Homogeneous KSc2F7 microcrystals with controlled and abundant morphologies were prepared by a one-step hydrothermal route without employing any templates or surfactants. Particularly, uniform and well-defined KSc2F7 crystals with rod, sheet, flower-like, thin rectangular, xylitol-like and thin plate morphologies were achieved by manipulating the different environments of crystal growth, such as increasing the concentration of F−, changing pH and adding different surfactants. In addition, a phase transformation from monoclinic ScF3 to orthorhombic KSc2F7 was observed at different molar ratios of F/Sc and pH values, respectively. A more interesting thing is that the KSc2F7 crystals doped with 5% Ln3+ (Ln = La, Ce, Sm, Eu, Gd, Tb and Lu) showed rich morphologies and various sizes. The obtained KSc2F7:Ln3+ products showed multicolor emission with red (Eu3+), green (Tb3+) and blue (Ce3+), respectively. And the best emission conditions for KSc2F7 crystals are F/Sc/K = 3.5 : 1 : 3, pH = 7 and without any surfactants. The synthetic KSc2F7:Eu3+/Tb3+/Ce3+ phosphors may potentially be used for multicolor illumination and displays.

Tin oxide (SnO2)-based electron transport layers (ETLs) are used to make flexible perovskite solar cells (PSCs) because of their low-temperature properties. However, when pure SnO2 is used, the poor interface formed between the SnO2 ETL and the perovskite layer is detrimental to the efficiency of the PSCs. In this work, we report the synthesis and characterisation of a SnO2–NaCl composite ETL. Na+ and Cl− at the ETL/perovskite interface passivate the ETL/perovskite contact and suppress nonradiative recombination centres. Meanwhile, Na+ diffuses from the ETL to the perovskite film, passivating its grain boundaries. The outstanding capability of Na + to increase the grain size and consequently improve the charge dynamics and increase the power conversion efficiency was also verified. PSCs with a SnO2–NaCl ETL exhibited an open-circuit voltage of 1.11 V, which was higher than the reference (1.08 V) for lower band gap perovskite absorbers, and achieved a power conversion efficiency of 18.56% with negligible hysteresis.

The flexible TiC/carbon nanofiber (TiC/C NF) film was prepared by electrospinning, stabilization, and carbonization. All the obtained TiC/CNFs had rough surface and random orientation, and the TiC nanoparticles (NPs) were uniformly dispersed on the CNFs. With the increase of TiC NPs, the flexural property of TiC/CNF film increased. While, the electrical conductivity increased, reaching a largest value before decreasing as the amount of TiC NPs increases. These highly flexible films showed promising electrical conductivity and electrocatalytic activity. Hence, they were employed as counter electrodes (CEs) for flexible dye-sensitized solar cells (FDSSCs). After the optimization of the amount of TiC NPs in CNFs (when the Tip content in precursor was 12 wt%), a high conversion efficiency of 3.80% was obtained. This is due to its optimum electrical conductivity and catalytic active sites. Based on the optimum amount of TiC NPs, the mesopores TiC/CNF composite films were fabricated by the introduction of various amount of polymethyl methacrylate (PMMA) in an electrospun solution. With the ratio of PMMA/(PAN/PVP) increasing, the specific surface area and the electrical conductivity increased, reached the largest values corresponding to 1:1, and then decreased. The increased surface area and conductivity facilitated the diffusion of electrolyte and reduction of triiodide, resulting in the improvement of the properties of CEs. When the FDSSCs were assembled with mesoporous TiC/CNF films as CEs, the conversion efficiency can be further enhanced up to 4.47%, which can be even comparable to the Pt/FTO CE.

Application of traditional electrospun scaffolds in tissue engineering is limited due to the sheet-like nanofiber layers hindered cell infiltration. In this study, a three-dimensional (3D) thick nanofiber stack with pore size gradient was fabricated via a novel electrospinning setup. Instead of a traditional flat-plate collector, a small copper plate which covered a hole of PMMA sheet was connected to negative voltage, resulting in focused collection of nanofibers and quickly enhanced scaffold thickness due to insulating PMMA preventing fibers from spreading elsewhere. The average pore size can reach more than 25 μm which benefit for cell infiltration. In the process of electrospinning, the mat with increased thickness may influence the electric field and has effect on fiber diameter and pore size.

Electrospun polyurethane (PU) based nanofibrous mats were fabricated from the solutions prepared with different volume ratios of N,N-dimethylformamide (DMF), methanol (MeOH), and dichloromethane (DCM). The membrane structures such as the nanofiber diameter, the pore size distribution, and the porosity were investigated in detail. And the morphological, mechanical, waterproof, and breathable properties of the membranes were used to estimate the characteristics of the membranes. Various solutions were compared to obtain porous nanofibrous membranes without beads or curls, which revealed that morphologies of PU fibrous membranes could be finely regulated by tuning the solvent volume ratios and the solution concentrations. The results showed that the nanofibrous membranes with the DMF/DCM solvents exhibited the high fiber diameter (500–700 nm) and the wide pore size distribution (0.6–1.2 µm). Besides, the water contact angle (WCA) of the PU nanofibrous film using the 100% DMF was 133°, but it could not persist for a long time. And the resultant membranes presented high hydrostatic pressure to 2.1 kPa, modest water vapor transmission rate of 10.1 kg/m2/day, as well as robust mechanical properties with tensile strength of 6.6 MPa, which are desirable in many important applications including protective clothing.

The novel columnar liquid crystals based on symmetric hairpin-shaped cholesterol tetramers bridged by rigid or hydrogen-bonding Schiff-base spacers were prepared by reacting cholesterol dimer with phenylenediamines or dihydrazides in yields of 70–85%. Structural characterisation of these new compounds had been achieved by infrared, nuclear magnetic resonance and mass spectrometry. Their mesomorphic properties were investigated by polarising optical microscopy, differential scanning calorimetry and X-ray diffraction. They exhibited good hexagonal columnar mesophase with three molecules in a disc of the columnar hexagonal state. This study implied that the symmetric cholesterol tetramers with rigid cores or hydrogen-bonding cores prefer to columnar mesophase.

A novel a / c grain boundary with well-defined facet of the YBa 2 Cu 3 O 7 − δ (Y123) film featuring a single-crystalline nature was successfully grown by liquid phase epitaxy, differing from conventional ill-defined facet film possessing a polycrystalline characteristic by the prior art deposition techniques. Here the extremely low supersaturation as essential prerequisite was exploited on (110) NdGaO 3 (NGO) substrates with partly-etched c -axis Y123 films. Based on the selective growth, preferred a -axis Y123 hetero-epitaxially grew on the bare NGO directly while c -axis Y123 homo-epitaxially proceeded on pre-existing Y123, consequently fabricating a distinct a / c grain boundary, which has great importance for fundamental studies and device applications.

The effects of Gd content on crystalline orientation, microstructure and superconductivity of Gd x Y1−x Ba2Cu3O7−δ (GdYBCO) films were systematically investigated. By varying the Gd content in the liquid precursor without changing the total amount of rare earth elements, series of GdYBCO films with x values of 0, 0.1, 0.3, 0.5, 0.7, 0.9 and 1.0 were fabricated by metal organic chemical vapor deposition (MOCVD). X-ray diffraction (XRD) and scanning electron microscope (SEM) analysis revealed that Gd introducing could restrain the formation of CuYO2 phase, but induce a-axis growth of GdYBCO film. The increase of x from 0 to 0.5 leads to enhancing critical current density at self-field and 77 K (J csf) from 1.8 to 2.8 MA·cm−2, which benefits from the decrease in CuYO2 impurities and improvement of in-plane texture from 5.0° to 4.3°. However, raising x from 0.5 to 1.0 gives rise to abundant a-axis growth of film and degradation of in-plane texture from 4.3° to 5.4°, consequently resulting in the decrease of J csf from 2.8 to 0.8 MA·cm−2. Even though J csf has not varied monotonically, the critical transition temperature of GdYBCO films linearly increases from 90.75 to 92.25 K and the in-field performance at magnetic field (B) of 0–1.1 T and 77 K as well as B parallel to film normal is also superior with Gd content increasing.

High-performance electrocatalysts for water splitting at all pH values have attracted considerable interest in the field of sustainable hydrogen evolution. Herein, we report an efficient electrocatalyst with a nanocrystalline cobalt phosphide (CoP) network for water splitting in the pH range of 0–14. The novel flexible electrocatalyst is derived from a desirable nanocrystalline CoP network grown on a conductive Hastelloy belt. This kind of self-supported CoP network is directly used as an electrocatalytic cathode for hydrogen evolution. The nanocrystalline network structure results in superior performance with a low onset overpotential of ~45 mV over a broad pH range of 0 to 14 and affords a catalytic current density of 100 mA·cm−2 even in neutral media. The CoP network exhibits excellent catalytic properties not only at extreme pH values (0 and 14) but also in neutral media (pH = 7), which is comparable to the behavior of state-of-the-art platinum-based metals. The system exhibits an excellent flexible property and maintains remarkable catalytic stability during continuous 100-h-long electrolysis even after 100 cycles of bending/extending from 100° to 250°.

In this work, we report a novel battery-type electrode of three-dimensional hierarchical Co3O4@NiMoO4 flower-like hybrid arrays on Ni foam synthesized with the combination of hydrothermal and post-annealing treatment. The Co3O4 nanowire arrays are utilized as scaffolds and interconnected NiMoO4 nanosheets are grown on the surface. The as-prepared Co3O4@NiMoO4 hybrid arrays exhibit outstanding electrochemical performance in terms of specific capacity (636.8 C/g at 5 mA/cm2) and cycling stability (84.1% retention over 2000 cycles at 20 mA/cm2). The assembled hybrid supercapacitor device based on Co3O4@NiMoO4 and activated carbon as the positive and negative electrodes can achieve a high energy density of 58.5 Wh/kg at 389 W/kg, suggesting the great potential for applications in supercapacitors.