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Zr 50 Cu 34- x Fe x Al 8 Ag 8 (x = 0, 2, 4, 6, and 8) alloy bars of different diameters were prepared by copper mold suction casting and copper mold casting. The compressive mechanical properties of metallic glass samples with different Fe contents were determined by a universal testing machine. The microstructure and thermodynamics of the alloy samples were analyzed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and differential scanning calorimetry. According to the experimental results, Fe doping had a significant effect on the glass-forming ability, stability, and mechanical properties of these metallic glasses. The maximum diameter of the Zr 50 Cu 32 Fe 2 Al 8 Ag 8 metallic glass bar was 15 mm, and the cooling rate of the alloy sample was 7.7 K/s. The addition of Fe inhibited the formation of stable crystalline phases inside the alloy sample and improved the glass-forming ability of the metallic glass. With the addition of Fe, the DSC curve of the alloy sample moved to higher temperatures, and the characteristic temperatures and the stability of the metallic glass increased. The fracture strength (σ max) and ultimate strain (ε f) of the metallic glass samples reached their maximum values of 1917.6 MPa and 3.97 %, respectively, for Zr 50 Cu 30 Fe 4 Al 8 Ag 8. Compared with the Fe-free Zr 50 Cu 34 Al 8 Ag 8 metallic glass, σ max and ε f increased by 51.4 MPa and 1.19 %, respectively. With the addition of Fe, the change in the distribution and content of free volume inside the metallic glass sample is the main reason for the improvement of its mechanical properties. This study shows that trace element doping has an important effect on the properties of metallic glasses. [Display omitted] • Trace element doping significantly improves the properties of alloys. • The addition of Fe improves the glass-forming ability of metallic glasses. • Fe doping improves the mechanical properties of metallic glasses. • Distribution and content of free volume affect the deformation of alloys. [ABSTRACT FROM AUTHOR]

• Concentration gradient material is successfully synthesized detected by line scan. • XRD tests show that the samples doped with Mn have better layered structure. • TEM images show that the samples doped with Mn have more obvious lattice fringes. • After 200 cycles at 1 C, the capacity retention rate of G-LNM91 remains 87.5%. The cathodes of LiNiO 2 (LNO), Li[Ni 0.9 Mn 0.1 ]O 2 (LNM91) and the concentration gradient material Li[Ni 0.9 Mn 0.1 ]O 2 (G-LNM91) were synthesized by co-precipitation method, and SEM, XRD, TEM and electrochemical tests were performed. SEM images show that the primary needle-like particles on spherical surface of the gradient G-LNM91 are the densest. The results of EDX linear scan show that for gradient precursor G-NM91, the relative atomic content of Ni element gradually decreases from 98.21% at the center of the particle to 80.66% at the cross surface of the particle (the content of Mn from 1.79% gradually increases to 19.34%). For the final product G-LNM91, the relative atomic content of Ni element in the center decreases to 94.07%, and at the edge increases to 85.17%. XRD tests indicate that the samples doped with Mn have good layered structure. TEM images show that the lattice fringes of the samples doped with Mn are more obvious. The results of Electrochemical performance tests show that manganese substitution has a significant effect on improving the cycle performance of LiNiO 2 , and G-LNM91 has the best cycle performance. Under a voltage range of 2.75–4.3 V, the initial discharge capacity of G-LNM91 cathode material at 0.1 C is 200 mA h/g. After 200 cycles at 1 C, the capacity retention rate remains around 87.5%. The initial discharge capacity of LNM91 is 180 mA h/g and the retention rate is 78.5%; the capacity retention rate of LiNiO 2 is only 55.2%, even though the initial specific discharge capacity is 207 mA h/g. [ABSTRACT FROM AUTHOR]

Highlights: [•] The effects of Mn doping on structures, electric, magnetic, and magnetocapacitive properties of the 0.33Ba0.70Ca0.30TiO3–0.67BiFeO3 + x wt%MnO2 (BCT-67BF:Mn100x, x =0–0.6) ceramics have been intensively investigated. [•] The BCT-67BF:Mn100x ceramics with x =0–0.6 have diphasic tetragonal–rhombohedral phases. Mn doping improves the densification and significantly decreases the grain size. [•] As x increases, the relaxor degree increases, the ferroelectricity and piezoelectricity weaken monotonically, while the magnetism enhances firstly, reaching the maximum near x =0.5, and then decreases. [•] The room temperature relative dielectric constant shows an obvious increase with increasing applied magnetic fields (H), the magnetocapacitive coefficient (ε r(H)− ε r(0))/ε r(0) decreases with increasing Mn content, from 2.96% for x =0 – 0.86% for x =0.6 . [ABSTRACT FROM AUTHOR]

• The Au@mSiO 2 YSNs was synthesized by a facile one-pot method. • The synthesis of Au@mSiO 2 YSNs was a one-step synthesis of Au@mSiO 2 CSNs combined with organosilane-assisted etching process. • Au@mSiO 2 YSNs exhibited superior catalytic activity than that of Au@mSiO 2 CSNs in redox reaction of p-nitrophenol. • The evolution from Au@mSiO 2 CSNs to Au@mSiO 2 YSNs showed the enhanced SERS effect. The yolk-shell nanoparticles (YSNs) are promising functional nanomaterials for a variety of applications such as bio-medicine, catalysis, sensor, lithium battery and detection due to their unique structures and excellent properties. In the past few decades, the synthesis of YSNs generally requires multiple steps to complete, and the process is relatively tedious and complicated. Here, Au@mSiO 2 YSNs with good dispersibility were successfully synthesized by a facile one-pot process. The Au core with average diameter of 22 nm can move freely in the cavity and the silica shell with a thickness of 15 nm can effectively prevent Au particle aggregation. The method is a one-pot one-step synthesis of Au@mSiO 2 core-shell nanoparticles (CSNs) combined with an organosilicon-assisted etching process. Thanks to the unique properties of Au@mSiO 2 YSNs, such as low density and large surface area, we have conducted a series of studies on its properties. The redox reaction of p-nitrophenol (4-NP) was monitored by UV–vis absorption spectrum to investigate the catalytic performance of Au@mSiO 2 YSNs. The surface-enhanced Raman scattering (SERS) effect of Au@mSiO 2 YSNS was studied using p-aminophenol (PATP) as probe molecule. The results show that Au@mSiO 2 YSNs have higher catalytic activity and stronger SERS effect than that of Au@mSiO 2 CSNs. The Au@mSiO 2 YSNs will have great application prospects in catalysis, biosensing and detection, etc. [ABSTRACT FROM AUTHOR]

The power conversion efficiency (PCE) of monolithic perovskite/silicon tandem solar cells has surpassed that of silicon single-junction solar cells recently. Industrial textured crystalline silicon heterojunction solar cells are considered as competitive candidate bottom cells because of their high efficiency and simple process flow. Meanwhile, the front transparent conductive window layers with industrial compatibility and low processing temperature are worth investigating in detail. In this work, zinc-doped indium oxide (IZO) thin films achieved by room-temperature sputtering are studied as a function of sputtering powers. The IZO thin film with the resistivity and electron mobility of 7.2 × 10−4 Ω cm and 40.03 cm2/Vs are obtained under 85 W, which is implemented into the monolithic perovskite/silicon tandem solar cells. A PCE of 19.38% is realized based on the industrial textured silicon heterojunction bottom solar cell and optimized IZO films. • Industrial textured SHJ solar cells was used as the bottom cell of the PSSCs. • Optimal sputtering power of 85 W was obtained for the IZO films with the best FOM. • 60 nm IZO facilitates a higher short circuit current and a better current match between the sub-cells. • 1 cm2 two-terminal PSSC with PCE of 19.38% were demonstrated without additional anti-reflection layers. [ABSTRACT FROM AUTHOR]

Low field magnetoresistance (LFMR) of double perovskite Sr 2 FeMoO 6 (SFMO) is low at room temperature. In this paper, a low-cost, facile, and effective way to enhance the LFMR is developed. Single-phase SFMO ceramics with 10% Fe/Mo anti-site defects have been prepared, and then soaked in glycerin/water (1/1, V/V) mixture for 0–14 days. The insulating glycerin tends to segregate into the SFMO grain boundary to form organic/inorganic composite. Such a post-treatment has no effects on magnetic properties, but can increase the resistivity by ∼500 times, as the result, remarkable enhanced LFMR is observed in composites. With 0.5 T magnetic field, the LFMR of the SFMO soaked for 14 days reaches −29.5% at 10 K and −11.0% at 300 K, more than 2 times larger than that of the SFMO without soaking, which are −12.0% at 10 K and −4.7% at 300 K. Based on the experimental results, a possible mechanism is proposed to explain the relation between the composite structure and the LFMR response. We believe our work not only provides a novel method to enhance the magnetoresistance in SFMO ceramics, but also sheds light on tuning transport/magnetoresistance in other perovskite ceramics. [ABSTRACT FROM AUTHOR]

Abstract: A series of lead-free piezoceramics of (1− x)K0.5Na0.5NbO3–xBi0.8La0.2FeO3 [(1− x)KNN–xBLF, 0.005≤ x ≤0.04] were synthesized by conventional solid-state sintering. Crystal structures and microstructures of the ceramics were characterized by X-ray diffraction and transmission electron microscopy. X-ray diffraction substantiates the existence of an orthorhombic-tetragonal morphotropic phase boundary (MPB) near x =0.01. Highest electrical performances were observed near the MPB. The maximum remnant polarization, piezoelectric coefficient, and coupling factor were measured as 22.5μC/cm2, 144pC/N, and 0.34, respectively. The effects of BLF on structures and electrical properties were discussed. Our results might be helpful for developing KNN-based piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

● PLZST: x SnO 2 composite ceramics were prepared by solid state reaction. ● The composite structure had significant effects on microstructures and electrical properties. ● The optimal composition of x = 0.2 showed high energy storage density of 2.38 J/cm3. Constructing composite structure is an effective way to improve dielectric energy storage properties. However, ionic diffusion between composite members is generally inevitable, which mixes the effects of solid solution with composite structure on property to some extent. To exclude the ionic diffusion effect as much as possible, antiferroelectric (Pb 0.97 La 0.02)(Zr 0.5 Sn 0.4 Ti 0.1)O 3 (PLZST) was sintered at a relatively high temperature to precipitate SnO 2 particles, then more SnO 2 were introduced to from (1- x)PLZST: x SnO 2 (x = 0–0.25) composite. The results showed that composite structure had significant effects on microstructures and properties with changed lattice parameter, decreased grain size, increased Curie temperature, suppressed antiferroelectric property, and enhanced electric breakdown strength. The optimal composition of x = 0.2 showed high energy storage density of 2.38 J/cm3. This work provides a robust platform to investigate the effect of composite microstructure on electrical properties, which is helpful for further developing high performance composite materials. [ABSTRACT FROM AUTHOR]

Providing a driving force is an effective approach to boost the separation of photo-induced charge carriers. Photoelectrode application is the most accepted route. However, it is difficult to realize the high-efficiency photocatalytic activity of granular photocatalysts in suspension by applying the electric field. In this work, on the basis of the Lorentz force-driven improved separation of photo-induced charge carriers in TiO 2 nanobelts, further enhancement of the charge transfer was achieved through constructing a heterostructure of reduced graphene oxide (rGO)/TiO 2 nanobelts (NBs) in a magnetic field. The photocatalytic efficiency of the rGO/TiO 2 NB heterostructure improved by 34% compared with pure TiO 2 NBs under the same magnetic field conditions. This new strategy combined the Lorentz force generated in a magnetic field and the built-in electric field of rGO-TiO 2 NBs to improve photo-induced charge carrier separation and transfer. Furthermore, a wireless microelectric potential was generated in rGO based on the electromagnetic induction effect, which additionally improved the charge transfer in rGO. This work provides a new idea to improve the photocatalytic activity of granular photocatalysts. ga1 • Combining Lorentz force and build-in electric potential to boost charge separation and transfer for powder photocatalysts. • The photocatalytic efficiency of rGO/TiO 2 nanobelts heterostructure in magnetic field can be improved by 107%. • Provide a new idea to boost photocatalytic activity based on external magnetic field and heterostructure. [ABSTRACT FROM AUTHOR]

La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ (LSCF) is a promising cathode material for solid oxide fuel cells (SOFCs). Hence, structured LSCF coatings were deposited in this study by atmospheric laminar plasma spraying (ALPS) at the spraying distances from 150 mm to 250 mm. Particles with high temperature were obtained at low plasma arc power of only 15 kW. The microstructural characterization of the coatings showed cluster-like morphologies on the top surfaces and columnar features with large-scale vertical cracks at the cross section. An evolution mechanism of the coatings was proposed based on particle size. The movement of particles during laminar plasma jet depended on particle size, which was studied experimentally and by simulation to explain the selective deposition. The coatings showed lower polarization resistance when compared to LSCF coatings deposited by atmospheric plasma spraying (APS) due to large vertical crack densities. The high output performance of the SOFCs with the LSCF cathode also proved this phenomenon. The results suggest that ALPS provides extensive options for SOFCs manufacturing. • LSCF coatings were deposited at the long spraying distances, although at low plasma arc power of only 15 kW. • The selective deposition depended on particle size was proposed to explain various structures of coatings. • Structured coatings with large-scale vertical cracks revealed lower polarization resistances compared to APS coatings. [ABSTRACT FROM AUTHOR]

In this paper, CaIn 2 S 4 films with vertically aligned and interconnected hierarchical nanosheets were directly fabricated on tin-doped indium oxide (ITO) substrate via a facile hydrothermal process with no additional directing agent. The crystal structure, morphology and optical properties of the obtained CaIn 2 S 4 films were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and UV–vis spectra. The results revealed the successful synthesis of uniform CaIn 2 S 4 hierarchical nanosheet films on ITO substrate with a whole thickness of about 3 μm and an average nanosheet thickness of about 20 nm, with the band gap of 2.17 eV. A possible mechanism for the formation of CaIn 2 S 4 films in hydrothermal process has been proposed. The CaIn 2 S 4 hierarchical nanosheet films exhibited a photocurrent density of approximate 0.2 mA cm−2 at 0.82 V (vs. NHE) in a neutral solution. In addition, the CaIn 2 S 4 films also exhibited superior photocatalytic activity for methyl orange and 1-naphthol. This study provided a green and facile method for the synthesis of high-quality CaIn 2 S 4 films applied in photocatalytic water splitting and photodegradation of organic pollutant. • Hierarchical nanosheet CaIn 2 S 4 films were fabricated by a hydrothermal process. • The CaIn 2 S 4 films exhibited good PEC performance in a neutral solution. • The CaIn 2 S 4 films demonstrated good MO and 1-naphthol degradation activity. • The structural and morphological properties of CaIn 2 S 4 films were characterized. [ABSTRACT FROM AUTHOR]

0.8Na 0.5 Bi 0.5 TiO 3 -(0.2- x)K 0.5 Bi 0.5 TiO 3 - x Bi(Zn 0.5 Ti 0.5)O 3 (NBT-KBT-BZT, x = 0–0.05 with interval of 0.01) lead-free piezoceramics were prepared and investigated. The addition of BZT has not led to deviation of rhombohedral-tetragonal morphotropic phase boundary, but apparently composition-dependent electrical property and monotonously improved thermal stability. The x = 0.02 has the optimal electrical property with remnant polarization, bipolar total strain, piezoelectric constant of 26.5 μC/cm2, 0.30%, 121 pC/N respectively, while the depolarization temperature is increased from 93 °C for x = 0–135 °C for x = 0.05 based on dielectric measurement. Detailed investigation reveals that the domain structure transforms from labyrinthian domain for x = 0 to coexistence of nanodomain and labyrinthian domain for x = 0.02, end up with large amount of nanodomain (x = 0.04). Such domain evolution should be responsible for the composition dependent electrical property and improved thermal stability. Our work confirms that domain engineering is an alternative method to develop high performance piezoelectric materials. • NBT-KBT-BZT lead-free piezoceramics have been prepared. • The piezoceramics show composition-dependent property and improved thermal stability. • Domain transforms from labyrinthian domain, coexisted nanodomain and labyrinthian domain, to nanodomain. [ABSTRACT FROM AUTHOR]