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In this study, Ag/α-Fe 2 O 3 /g-C 3 N 4 composites with varying α-Fe 2 O 3 and Ag contents were synthesized by loading α-Fe 2 O 3 and Ag nanoparticles onto the g-C 3 N 4 with a high specific surface area via acid annealing. These composites were then utilized for the photocatalytic degradation of RhB under the irradiation of visible light. For α-Fe 2 O 3 /g-C 3 N 4 composites with 5 wt% content of α-Fe 2 O 3 , the degradation efficiency reached a peak of 97.57% within 55 min, which was much higher than that of α-Fe 2 O 3 and acid-annealed g-C 3 N 4 with 45.92% and 83.61%, respectively. Furthermore, the photocatalytic degradation efficiency of Ag/α-Fe 2 O 3 /g-C 3 N 4 composites reached its maximum of 99.61% with 1% content of Ag. It was demonstrated that the ternary Z-scheme heterojunction construction leaded to a significant enhancement of carrier separation and transfer effects, while the incorporation of Ag serves as electron reservoirs and photoinduced electrons capturers, thereby significantly enhancing the Fenton reaction and photocatalytic performance. This work is significant to drive the widespread application of g-C 3 N 4 based heterojunctions in photocatalytic water purification. • Ag/α-Fe 2 O 3 /g-C 3 N 4 Z-scheme heterojunction with a high specific surface ares were successfully synthesized. • α-Fe 2 O 3 /g-C 3 N 4 composites with α-Fe 2 O 3 from 2 wt% to 10 wt% were prepared, it was found that the photocatalytic degradation efficiency reached a peak of 97.57% within 55 min with 5 wt% content of α-Fe 2 O 3. • The photocatalytic degradation efficiency of Ag/α-Fe 2 O 3 /g-C 3 N 4 composites reached its maximum of 99.61% with 1% content of Ag. • It was demonstrated that the Z-scheme heterojunction construction of α-Fe 2 O 3 /g-C 3 N 4 greatly enhanced the carrier separation and transfer effects, while the incorporation of Ag serves as electron reservoirs and photoinduced electrons capturers. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) Pt-based multi-metallic nanostructures have been demonstrated to be used as outstanding electrocatalysts for direct alcohol fuel cell owing to the merits of raising electrocatalytic activity and enhancing the durability of catalysts as well as saving Pt utilization. Herein, we develop an interface-confined strategy, achieving 2D close-packed AuPtTe nanotrough array. This strategy involves two steps: (1) assembly of Te nanowires into 2D monolayer array at hexane/water interfaces, and (2) transformation of 2D interfacial Te nanowire array into AuPtTe nanotrough array by interface-confined etching of PtCl 6 2– and AuCl 4 – in the water subphase. Optimized 2D Au 74 Pt 23 Te 3 nanotrough array exhibits ∼3.36 and ∼2.15 A mg Au+Pt –1 in the mass activity towards ethanol and methanol electrooxidation, respectively, ∼5 and 3 times that of commercial Pt/C, and shows superior durability to Pt/C, which may be attributed to the synergistic effects of the trough-like morphology and optimal composition. This work may open up a new perspective on the designing of components, morphologies, and compositions of advanced catalysts. [Display omitted] • A novel interface-confined strategy is developed for processing Te nanowire. • 2D Au 74 Pt 23 Te 3 nanotrough array with coral-like bottom layer is constructed. • Au 74 Pt 23 Te 3 shows excellent activity and stability for alcohol electrooxidation. • The amazing performance is due to the synergy of novel structure and composition. [ABSTRACT FROM AUTHOR]

Zirconia (ZrO 2) is a hard and brittle dental implant material without anti-infective property. This work reports the preparation of a tertiary micro-nano hierarchical structure on a ZrO 2 surface via femtosecond laser texturing combined with magnetron sputtering deposition of an Ag layer (Ag/ZrO 2), aiming to achieve a superhydrophobic synergistic antibacterial effect. Laser-scanning pitch and Ag layer thickness were systematically optimized for obtaining the tertiary hierarchical structure. The wettabilities, antibacterial properties and durabilities of various ZrO 2 and stearic acid modified Ag/ZrO 2 (S-Ag/ZrO 2) surfaces were further tested and comparatively analyzed. The results revealed that the optimal process parameters were a laser-scanning pitch of 30 μm and an Ag layer thickness of 100 nm. The as-obtained S-Ag/ZrO 2 sample displayed a tertiary micro-nano hierarchical structure, which was featured by a periodic regular conical micro-convex structure covered with ZrO 2 nano-protrusions and Ag nanoparticles. This structure could not only greatly reduce the solid-liquid contact area to achieve outstanding superhydrophobicity and durability, it could also sustainably release bacteria-killing Ag+ to obtain an antibacterial ratio of 95.1 % and ensure a long-term antibacterial effect. In addition, the optimal S-Ag/ZrO 2 sample having this structure showed a PC12 cell survival rate of up to 81.75 %, demonstrating its good biocompatibility. This work may be of great inspiration and reference for the expansion of the use of ZrO 2 in dentistry. [Display omitted] • Femtosecond laser texturing and sputtering Ag layers were performed on ZrO 2 surfaces. • A tertiary micro-nano hierarchical structure was formed on the best Ag/ZrO 2 surface. • ZrO 2 -based surfaces under different treatment conditions were compared and analyzed. • The stearic acid modified Ag/ZrO 2 (S-Ag/ZrO 2) surface exhibited superhydrophobicity. • The best S-Ag/ZrO 2 surface achieved excellent antibacterial property and durability. [ABSTRACT FROM AUTHOR]

Nowadays, Fe-based microwave absorption materials still face crucial problems of poor oxidation resistance, lack of dielectric loss and narrow effective absorption bandwidth. In this work, we developed a feasible way of calcining and etching SiO 2 microspheres coated Fe3+ and polydopamine (SiO 2 @Fe3+-PDA) to confine Fe nanoparticles (12 nm) in the hollow carbon microspheres with a thickness of 17 nm, which provides more interfaces and polarization sites to enhance microwave attenuation. With the increase of Fe content, the microwave absorption performance of the sample is gradually improved. When Fe content is 19.7 wt%, the sample has a minimum reflection loss (RL) of −30.9 dB and a broadband absorption bandwidth (RL ≤ −10 dB) of 11.9 GHz (6.1–18 GHz) at the thickness of 4.0 mm. The ultra-wide effective absorption bandwidth is ascribed to synergetic effect of Fe nanoparticles and carbon layer, which provide magnetic loss and dielectric loss, respectively. Moreover, the hollow structure extends the transmission path and induces the multiple scattering of the incident electromagnetic waves. The novel hollow Fe/C microspheres are promising as high-efficiency microwave absorbers with strong microwave absorption and broad absorption bandwidth. [Display omitted] • Hollow Fe/C microspheres are fabricated using SiO 2 @Fe3+-PDA microspheres. • Fe nanoparticles are embedded in 17 nm carbon shell. • An ultra-wide effective absorption bandwidth of 11.9 GHz is obtained. • Fe/C-3 sample exhibits a minimum reflection loss value of −30.1 dB. [ABSTRACT FROM AUTHOR]

The superimposition of multiple factors has presented a formidable challenge in establishing the salient features of grain size distribution for the large-scaled complex titanium alloy casting (LCTAC). In this study, an anatomical analysis within a LCTAC was conducted to acquire microstructure and mechanical properties distribution characteristics in typical zones. Through the progressive convergence, variable selection, and data dimensionality reduction techniques employed in the LASSO regression of microstructure characteristics and mechanical properties, the efficacious establishment of microstructural attributes has been accomplished. Consequently, a quantitative relationship between the microstructure and properties of the LCTAC has been formulated, predicated on the characteristics of grain size distribution. The findings unequivocally illustrate that the order of convergence for the microstructural parameters affecting the tensile strength of the LCTAC is as follows: expectation of grain size, mean grain size, full width at half maximum of grain size distribution, and the 99th percentile grain size. There exists a linear negative correlation between the 99th percentile grain size and tensile strength for the LCTAC, with a root mean square error in tensile strength prediction of less than 2%. • An anatomical analysis is performed within the large-scaled complex titanium alloy casting (LCTAC). • LASSO regression is introduced to augment the precision of quality assessment and control for the LCTAC. • A novel microstructural determinant influencing the tensile strength of the LCTAC is discovered. • A quantitative correlation between grain size distribution and mechanical properties within the LCTAC is established. [ABSTRACT FROM AUTHOR]

We present a combined electron microscopy and first-principles calculation study on the dominant formation of ultra-fine Y-Ti-Ta-O nano-oxides in Ta+B micro-alloyed 13CrWTi-ODS alloys fabricated by mechanical alloying, HIPing and annealing. These Y-Ti-Ta-O nano-oxides are suggested to be mostly Y 2 (Ti,Ta) 2 O 7 , with a mean size of ∼7 nm and a number density of ∼6.8 × 1023 m−3. They are most likely formed as a consequence of Ta substitution in early-precipitated Y 2 Ti 2 O 7 nano-oxides. Very a few low nm-sized yttrium borides can be also induced. Besides, excess B can be strongly attractive to both the Fe/Y 2 Ti 2 O 7 interface and grain boundaries (GBs), which may slightly enhance the adhesion of some low-Σ GBs but slightly weaken the Fe/Y 2 Ti 2 O 7 interface. Excess Ta can enhance the Fe/Y 2 Ti 2 O 7 interface, but can be more attractive to GBs, causing serious degradation and even loss of adhesion. Therefore, although Ta+B micro-alloying shows great benefits in refining both grains and nano-oxides, their alloying amounts must be restricted to the minimum necessary level. • Ta+B micro-alloying effectively refined grains and nano-oxides in HIPed and annealed 13CrWTi-ODS alloys. • The ultra-fine Y-Ti-Ta-O nano-oxides was formed by Ta partition into early-precipitated Y 2 Ti 2 O 7 nano-oxides. • Micro-alloying amounts of Ta and B must be restricted to minimize their adverse effects on internal interfaces. [ABSTRACT FROM AUTHOR]

The change of layer thickness can effectively influence the solidification condition and thermal history of the Al-5Si-1Cu-Mg aluminum alloy fabricated by laser additive manufacturing, and thus affect the microstructures and mechanical properties. Samples with ultrafine grain structures and excellent mechanical properties were successfully fabricated, and the microstructure and mechanical property differences related to the variations of layer thickness were systematically investigated. Results indicate that when higher layer thickness is employed, columnar grain structure is established with {100} Al texture due to high temperature gradient, while decreasing the layer thickness promotes the formation of equiaxed grains. Lower layer thickness sample with finer near-equiaxed grain structure has improved elongations. However, the strength is unexpectedly poorer than the higher layer thickness sample with near-columnar grain structure. The comparably better plasticity but poorer strength is attributed to the relatively coarser microstructure within grains, i.e. larger primary dendrite arm spacing with Si phases distributing more dispersed, introduced by more heat effect of subsequent deposition when applying lower layer thickness. For near-columnar sample, the cracked Si phases with different spacings perpendicular to loading direction would result in different microcrack coalescence behaviors and thus cause plasticity anisotropy. Whereas for near-equiaxed sample, due to the tailored distribution of Si phases, the direction-dependent elongation discrepancy is reduced. • High-property Al-5Si-1Cu-Mg samples were produced by laser additive manufacture. • The microstructure and tensile property related to layer thickness are examined. • Near-columnar and near-equiaxed grain structures are formed for different samples. • Near-equiaxed sample exhibits better plasticity but slightly lower strengths. • Plasticity anisotropy is lessen in near-equiaxed one and the mechanism is studied. [ABSTRACT FROM AUTHOR]

Abstract Two-dimensional (2D) nanostructures, though promising in energy storage, suffer from aggregation and subsequent deterioration of performance in practical applications. Hence, assembly of 2D nanostructures into three-dimensional (3D) architectures is highly desirable. Here, we report a microwave-assisted approach to the controllable synthesis of 2D materials with tunable 3D structures simply by adjusting the ratio of water/ethylene glycol (H 2 O/EG). Novel flower-on-sheet 3D hierarchical structures of nickel cobalt double hydroxide (NiCo LDHs) are obtained at EG content of 40%, while microspheres and 2D nanosheets are obtained when the EG content is 0% and 75%, respectively. We propose that under microwave irradiation, EG molecules disperse the nuclei and facilitate the initial formation of 2D sheets. Subsequently, the dominating hydrophobicity of the assembling results in the formation of nanoflowers on the sheets. When tested as electrode materials in supercapacitors, the flower-on-sheet NiCo LDH exhibits superior capacitance (1187.2 F g−1 at 1 A g−1), good rate capability (71% retention at 30 A g−1), and high stability (only 0.3% cyclic decay per cycle with respect to the first charge capacitance), which is ascribed to that 'sheet' could act as buffer substrate while 'flower' expose more active site. Our results demonstrate an energy-saving and one-pot approach for controllable construction of 2D derived 3D nanostructure that can be applied in next-generation energy storage materials. Highlights • Novel 3D flower-on-sheet structure of NiCo LDH was obtained via a microwave method. • The role of ethylene glycol in tuning the 3D morphology of NiCo LDHs was studied. • The flower-on-sheet structure enabled fast ion-diffusion and ion-available sites. • Highest capacitance and rate capability were gained for flower-on-sheet structure. [ABSTRACT FROM AUTHOR]

Abstract A novel spinel Li 1-x Ag x Fe 5 O 8 (0 ≤ x < 0.2) solid solution ceramics were fabricated via solid state reaction method. Based on XRD and SEM analysis, it was found that the spinel solid solution was formed in limited composition range. Both the dielectric and magnetic properties have been improved a lot, and the Li 0.95 Ag 0.05 Fe 5 O 8 sample achieved the higher the real part of both permittivity and permeability as 170 and 47.1, respectively at 200 MHz and 20 MHz, which was attributed to the Ag+ substitutions. Considering its dielectric and magnetic properties, the Li 1-x Ag x Fe 5 O 8 (0 ≤ x < 0.2) ceramics provide a way in developing multifunctional materials for multifunctional electronic devices applications. Highlights • The cubic spinel ferrite: a novel ceramic that Ag doped into LiFe 5 O 8. • Dielectric and magnetic performance of the lithium ferrite were improved remarkably. • Increase of the real permittivity of the Li 0.95 Ag 0.05 Fe 5 O 8 material up to 41.2%. [ABSTRACT FROM AUTHOR]

Abstract Nitrogen-enriched graphene coupled with nickel hydroxide nanosheets (Ni(OH) 2 /NG) hydrogel is successfully synthesized through a facile one-pot hydrothermal method. Comprehensive investigations reveal that the nitrogen atoms are successfully inserted into graphene and that the nickel hydroxide nanosheets (∼30–50 nm) are anchored on NG homogeneously. With the enhanced electroactivity caused by nitrogen doping and the synergy effect from Ni(OH) 2 nanosheets and NG, the Ni(OH) 2 /NG hydrogel electrode displays much better electrochemical properties than two individual electrodes. It features a specific capacitance as high as 896 F g−1 at 0.5 A g−1 and even 504 F g−1 at 12 A g−1 showing a high rate capability (56.3% retention with 24 times higher current density). An asymmetric supercapacitor device on the basic of Ni(OH) 2 /NG hydrogel and activated carbon (AC) was assembled and delivered a high energy density of 28.7 W h kg−1 at the power energy density of 0.36 kW kg−1. Such results indicate that the Ni(OH) 2 /NG hydrogel could be considered as a promising candidate for electrochemical supercapacitors. Graphical abstract Image 1 Highlights • The Ni(OH) 2 /NG hydrogel composite was synthesized by a facile route. • The composite electrode material displays excellent electrochemical properties. • An asymmetric supercapacitor is fabricated and exhibits a desirable energy density. • Excellent electrochemical performance is primarily attributed to the nitrogen doping and the synergy between the components. [ABSTRACT FROM AUTHOR]

Abstract Micro-arc oxidation (MAO) corrosion-resistant coating was prepared on AZ31Mg with MAO technique, and galvanic corrosion performance of the coated AZ31Mg coupled to 2024Al and 7075Al was studied. The results showed that the MAO coating can significantly protect AZ31Mg from galvanic corrosion and crevice corrosion. The lifetime of AZ31Mg with MAO coating coupled to 2024Al and 7075Al was 2184 h and 1800 h, respectively, when the surface corrosion morphology rating was 5. While it was only 264 h and 240 h for AZ31Mg. The MAO coating made the constraint of life-span of the coupled components changing from the anode corrosion of AZ31Mg to the corrosion of aluminum alloys and decreased the mass loss rate of the components greatly. This work had significant meaning to the applications of Mg alloys. Highlights • Micro-arc oxidation coating was prepared on AZ31Mg to protect it from corrosion. • Galvanic corrosion of MAO/AZ31Mg coupled to Al alloys was investigated. • The results showed the MAO coating protected AZ31Mg from corrosion efficiently. • MAO coating changed AZ31Mg from anode corrosion to cathode corrosion. • MAO coating slowed down the corrosion of both AZ31Mg and Al alloys significantly. [ABSTRACT FROM AUTHOR]

Abstract To resolve the worldwide water scarcity crises, there is an urgent need to develop highly efficient adsorbent for water purification. For the first time, Copper Iodide (CuI), homogeneously coating on carbon cloth (CuI@CC), is fabricated and investigated as a highly efficient, self-cleaning and easy-recycling adsorbent toward cationic organic dyes with good repeatability. Using the carbon cloth as a substrate, CuI is fabricated successfully via electroplating deposition followed by iodination procedure at ambient temperature. By combining the flexibility from the carbon fiber with the splendid adsorptive ability of the CuI coating, the CuI@CC is not only free-standing and flexible but also a highly efficient adsorbent. Notably, the CuI coating is also self-cleaning to decompose adsorbed organics through photocatalysis, which guarantees its great repeatability to a great extent. By installing the CuI@CC on the designed filtration device, the procedure of recycling and application is convenient and can avoid secondary pollution of water as well. This newly developed CuI coating is expected to be a novel adsorbent as a promising solution to the water crisis. Graphical abstract Image 1 Highlights • Novel CuI coating on carbon fiber was designed and successfully fabricated for the first time. • It exhibited a highly absorptive efficiency toward cationic dyes. • It possesses a splendid self-cleaning characteristic under UV light. • CuI@CC is free-standing and flexible with excellent recyclability. [ABSTRACT FROM AUTHOR]

Abstract Inconel 718 (IN718) superalloy has been fabricated by selective laser melting (SLM) technology, and the effects of the solution and double aging treatment on the microstructures and mechanical properties of the alloy have been studied. Under the same aging condition, the hardness of the IN718 superalloy first increased and then decreased with the increasing of the solution temperature. When the solution temperature was 980 °C, the average microhardness of the alloy was increased to 502 HV 0.2 , with 17.56% increase. With the solution temperature increasing, more short-rod δ phase (Ni 3 Nb) was precipitated at the grain boundaries and distributed homogeneously, and the γ′′ phase (Ni 3 Nb) and the γ′ phase (Ni 3 (Al, Ti)) were formed. The δ phase (Ni 3 Nb) can pin grain boundary, inhibit the grain growth and improve the mechanical properties. In addition, the corrosion resistance of the alloy decreased after heat treatment. After heat treatments, the formation of the second phase subsequently increased the number of corrosion microbatteries and reduced the anticorrosive ability of the alloy. Highlights • The anticorrosive ability of IN718 alloys decreased after heat treament. • The second phase improve the property, but decrease the anticorrosive ability. • Giving good comprehensive mechanical properties after heat treament. [ABSTRACT FROM AUTHOR]

Abstract The selected-dissolution behaviour of metals after the film rupture determines the propagation of localized corrosion. Meanwhile, excessive Cl− aggregations and too fast resorption behaviour may prematurely lead to the loss of mechanical properties. In this study, the degradation behaviour and mechanical properties of the heat-treated Mg-2Zn-0.2Mn-xNd (MZM-xNd) in the simulated body fluid were analyzed using XRD, XPS, FT-IR, TEM, 3D/CLSM and AFM/SKPFM. Besides, the film formation and rupture mechanism were illuminated through the spectroscopic analysis, and its role on the propagation of localized corrosion was also discussed. The results demonstrate that the localized corrosion propagates inside the matrix (underneath the surface film layers) and exhibits a filiform-like corrosion morphology. Immersion and polarization tests together with morphology observations indicate that the MZM-0.6Nd has the moderate degradation rate by giving rise to the densification of the film layer, with the corrosion rate of 0.83 mm/y. However, the corrosion rate progressively increased (1.83 mm/y, 3.08 mm/y), as the Nd content increased (1.22%, 1.88%), due to the more large-size phases present in the matrix. It will exacerbate the corrosion resistance by facilitating the localized dissolution of the degradation layers, enhancing the adsorption for Cl− and promoting the mass transport, thereby retarding the self-healing capability and the occurrence of the localized corrosion. The significant improvement in mechanical strength of MZM-0.6Nd, with the ultimate tensile strength and elongation of 224 MPa and 19.2%, making it appear the ductile fracture feature with small dimples. It was attributed to the role of interactions with the fine-grained microstructure, the pinning dislocations, and the strengthening phases dispersedly distributed in the matrix. Highlights • Nd addition induced the phase characteristics on corrosion initiation was discussed. • The difference in Volta potentials between the matrix and phases were obtained. • Film features with various Nd modification were analyzed. [ABSTRACT FROM AUTHOR]

SBA-15 supported nickel phosphide particles with high dispersion were successfully synthesized by using deposition-precipitation method to introduce the Ni source. Strong interaction between the Ni precursor and SBA-15 support could form and prevent the precursor migration. So the deposition-precipitation method could lead to the infiltration within the pore walls of SBA-15 and thus very uniform dispersion of Ni source over the SBA-15 support. After temperature-programmed reduction (TPR) of the phosphate precursor, the nickel phosphide particles with high dispersion were obtained. The pore channel of the SBA-15 support could stabilize the Ni 2 P particles, preventing sintering after the high reduction temperature and shaping their morphology. The total sulfur capacity over Ni 2 P/SBA-15 is approximately 1 times higher than over the reference sample. Differences in selectivity to sulfur compound were observed for Ni 2 P/SBA-15 adsorbents with different loading. The selectivity to sulfur compound for Ni 2 P/SBA-15 adsorbent is correlated with the particle size of Ni 2 P crystallites. The synthesis of small Ni 2 P crystallite is promising for novel Ni 2 P-based adsorbent. [ABSTRACT FROM AUTHOR]

In this study, we developed a simple, low-cost and convenient method to fabricate grid structures of different scales on the surface of 6061 aluminum alloy via laser processing. By changing the line spacing (50, 150, 250, 300 μm) during laser beam irradiation, different sizes of the square-shaped unprocessed surface areas and cross groove structures could be achieved. By adjusting the area ratio between the accumulative microstructure and the unprocessed surface, the adhesion of a water droplet to the surface could be varied from a state of low adhesion (line spacing of 50 or 150 μm) to a state of high adhesion (line spacing of 250 or 300 μm). The results indicated that different surface wettabilities could be obtained on aluminum alloy surfaces through the combination of a crisscross groove structure and unprocessed surface, which together formed a square groove structure. Corrugated protuberances, granular bumps and pit texture were formed on the groove structure. The surface showed excellent superhydrophobic properties. The contact angle was as high as 154.6° and the sliding angle was 6° for a line spacing of 150 μm. In this case, the low adhesion led to a rolling and self-cleaning behavior. For the larger line spacings, the wetting state of the water droplet indicated a high adhesion to the surface and a transition of the Cassie-Baxter state to the Wenzel state. Surfaces with high adhesion are of great significance for water collection and preservation. The approach presented in this study provides a facile, low-cost and efficient method to fabricate superhydrophobic surfaces on all types of metallic materials for commercial applications. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) hierarchical architectures built from spherical assembly of nanowires/nanorods have found applications in a wide range of fields. However, although some literatures have reported their successful preparation, up to now, it is difficult to adjust the size of the building blocks of the 3D structures, which indeed largely affects the performance of the materials. In this work, by adopting metal ions and PVP modified carbon spheres as templates, we demonstrate a seed-mediated growing strategy to control Co 3 O 4 shapes to be 3D urchin-like hierarchical structures constructed from 40 nm-diameter nano-wires, or 3D coral-like ones assembled from thicker 100 nm-diameter nano-rods. XRD patterns show both structured Co 3 O 4 are cubic phase, and N 2 sorption demonstrates they own both mesopores and macropores. Besides, the obtained materials display good photocatalytic performance and reusability to degrade Congo Red dye. [ABSTRACT FROM AUTHOR]

The photocatalyst construction determines the cost and photoexcited charge kinetics, whereas reaction system design ensures the synergic utilization of photoexcited charges. Herein, a novel Au13@Pt/CdS hybrid nanomaterial was prepared and used for the coupling selective redox system of aromatic alcohols and nitroarenes. The Au13@Pt nanoparticles evenly and tightly anchored on CdS provided abundant e– enrichment sites and wider charge transfer channels and largely improved photocatalytic performance. After 4 h visible-light illumination (λ > 420 nm), the optimal 0.00115 % Au13@Pt/CdS sample displays that the theoretical yields of aniline (AL) and p -methoxybenzaldehyde (p -MBA) are up to 71.5 % and 94.7 % with an impressive selectivity of over 95 %, therefore, parts of the generated AL and p -MBA further formed Schiff base with a 24.3 % yield. Therefore, this work is expected to offer a way to fabricate a dual-functional photocatalyst for selective organic transformations (P-SOTs). A coupling mechanism of simultaneous SO p -MBA and SR of NB in one system was proposed by a series of physical and chemical characterizations combined with in suit DRIFTS and theoretical calculations. [Display omitted] • A novel Au13@Pt/CdS composite photocatalyst was synthesized. • The Au13@Pt/CdS composite realized the synergic utilization of photoexcited charges. • The intermediates and products were dynamically monitored by in situ DRIFTS. • A possible mechanism for enhancing photocatalytic activity was proposed. [ABSTRACT FROM AUTHOR]

In this study, single-phase yttrium iron garnet (YIG) ferrite was synthesized by sol-gel method, which was firstly used as the insulating layer to prepare Fe/YIG soft magnetic composites (SMCs). It was demonstrated that the Fe powders were uniformly coated with the YIG ferrite for the Fe/YIG SMCs. The influence of the YIG content on the soft magnetic properties of the Fe/YIG SMCs were investigated in detail, the results showed that the total core loss (P cv) of all Fe/YIG SMCs were smaller than pure Fe. The P cv firstly decreased with increase of the YIG content up to 1.0 wt% (P cv = 2460 mW/cm3, 4 mT/590 kHz), then increased with the increase of YIG from 1.0 wt% to 5.0 wt%. What's more, the effective permeability (μ e) of the Fe/YIG SMCs with YIG from 1.0 wt% to 3.0 wt% were higher than that of Fe, confirming both decreased core loss and improved permeability were accomplished in the Fe/YIG SMCs, which demonstrated that the YIG ferrite has good application prospects as new coating layer for SMCs used in medium to high frequency environments. • Single-phase Y 3 Fe 5 O 12 ferrite was firstly used as an insulating layer for soft magnetic composites (SMCs) and the Fe/YIG SMCs with YIG from 0 to 5.0 wt% were successfully prepared. • The total core loss (P cv) of all Fe/YIG SMCs were smaller than pure Fe. The P cv firstly decreased with increase of the YIG content up to 1.0 wt% (P cv = 2460 mW/cm3, measured at 590 kHz and 4 mT), then increased with the increase of YIG from 1.0 wt% to 5.0 wt%. • The effective permeability (μ e) of the Fe/YIG SMCs with YIG from 1.0 wt% to 3.0 wt% were higher than that of Fe. • Decreased core loss, improved permeability and AC magnetic performance were simultaneously accomplished in the Fe/YIG SMCs. [ABSTRACT FROM AUTHOR]

The Fe 3 O 4 /MnO 2 /RGOs (Reduced graphene oxide) sandwich-like nano-superstructures reported in this article were fabricated by using an eco-friendly mechanical stirring route at room temperature without any catalysts or templates. In this nano-superstructure, three-dimensional (3D) hierarchical MnO 2 shell was assembled by two-dimensional (2D) nanoplates and Fe 3 O 4 /MnO 2 core-shell was coated by RGO layers. The sandwich-like nano-superstructures show better electrochemical performance comparing to the pure MnO 2 and Fe 3 O 4 /MnO 2 nanoparticles. The maximum specific capacitance can reach 77.5 F/g at the current density of 0.5 A/g and maintain 35.0 F/g (55% of SC at 0.5 A/g) at the current density of 20 A/g. It was found that the electrocapacitive performances of the Fe 3 O 4 /MnO 2 /RGO electrodes are highly affected by the connection effectiveness between Fe 3 O 4 /MnO 2 particles and graphene layers. [ABSTRACT FROM AUTHOR]

Lead-free p-type AgSn 4 SbTe 6 based thermoelectric nanocomposites were fabricated by a process combining mechanical alloys (MA) and spark plasma sintering (SPS). It is found that dispersing SiC nanoparticles into the AgSn 4 SbTe 6 matrix can enhance the thermoelectric properties significantly. SiC nanoinclusions can increase the power factor mainly due to improved electrical conductivity while slightly increasing the Seebeck coefficient, in addition to reducing the thermal conductivity through enhancing phonon scattering. A high dimensionless figure of merit (ZT) value up to 1.0 at a relatively low temperature (723 K) is achieved in AgSn 4 SbTe 6 incorporated with a small amount (1 vol%) of SiC nanoparticles. This work validated the effectiveness of SiC nanodispersion in enhancing thermoelectric performance of AgSn 4 SbTe 6 , by which a simple process yields a high ZT equivalent to the record one reported for this materials fabricated by a melting process. [ABSTRACT FROM AUTHOR]

High-efficiency and thermal stability are two important factors of ideal microwave absorption materials (MAMs), which are becoming desired because of the more complex modern service environment. Herein, a novel quaternary magnetic core-shell-shell structure FeCo-Co@Fe 3 O 4 @SiO 2 (FCSF) has been fabricated by a facile and generic route. In this structure, the incipient oxidation temperature of magnetic core can be greatly increased from 523 K to 773 K by the Fe 3 O 4 /SiO 2 double shells, and the multiple magnetic heterointerfaces can generate electron transfer and spin-orbit interaction based on DFT calculations. The minimum reflection loss (RL min) and efficient absorption band (RL<−10 dB, f eff) of FCSF composites can reach up to −42.8 dB and 7.3 GHz with the thickness of 2 mm, due to the emerged electromagnetic loss mechanisms of interface polarization and exchange resonance. Moreover, owing to the optimized impedance matching and enhanced electromagnetic loss at elevated temperature, the RL min values of FCSF at 673 K and 773 K increase by 15.4% and 41.2% compared with that at 298 K, respectively. The results demonstrate that the FCSF composite can act as a promising candidate for high-efficiency MAMs in thermal environment, and the synthetic strategy of heterostructures in this work can also be applied to design other MAM systems. • A quaternary magnetic heterostructures FeCo-Co@Fe 3 O 4 @SiO 2 was synthesized. • Charge transfer and orbital interaction in magnetic heterointerface were verified. • The RL min and f eff of FCSF are −42.8 dB and 7.3 GHz at the thickness of 2 mm. • The RL min of FCSF at 773 K increase by 41.2% compared with that at 298 K. • The component and heterostructures cause the high-efficiency and thermal stable. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate a facile and green hydrothermal process without using any surfactant or template to synthesize SnO 2 nanoflowers (NFs)/graphene nanosheets (GNSs) composites as a high-performance electrode material for electric double layer capacitors (EDLCs). The crystal structure and morphology of the products were characterized by X-ray diffraction, scanning electron microscopy, and transition electron microscopy. The electrochemical properties were investigated by galvanostatic charge/discharge cycling and cycling voltammetry in a voltage range of −0.2–0.8 V. The results exhibit that the addition of GNSs did not change the tetragonal crystal structure of SnO 2 , and the GNSs were successfully coated on the flower-like surface of SnO 2 . The grain morphology of SnO 2 @GNSs composites has a flower-like appearance suggesting excellent electrochemical properties which were confirmed by electrochemical techniques. Compared with the GNSs, the SnO 2 @GNSs composites exhibit a high specific discharge capacitance of 126 F g −1 at 0.2 A g −1 and remains 98.2% after 2000 charge–discharge cycles. The combination of GNSs and SnO 2 could significantly improve the electrical conductivity, enhance the interactions between GNSs and SnO 2 NFs and provide more reaction sites, thereby resulting in improved electrochemical properties for the SnO 2 @GNSs composites in contrast with the pristine GNSs sample. The high specific capacity and long stability make the SnO 2 @GNSs nanocomposite as a electrode material for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

A ZnO nanorod-coated FTO film was prepared by sputtering an AZO layer on FTO glass, thermal annealing of the AZO/FTO film, and hydrothermal growth of ZnO nanorods at 70 °C on the annealed AZO/FTO film using zinc foils as zinc source. Two other ZnO nanorod-coated FTO films were also prepared by hydrothermal growths of ZnO nanorods on the FTO glass and the unannealed AZO/FTO film respectively for comparison purpose. The results were observed in detail using X-ray diffraction, scanning electron microscopy, water contact/sliding angle measurement, spectrophotometry and four-point probe measurement. The ZnO nanorods on the annealed AZO/FTO film were found to exhibit denser distribution and better orientation than those on the FTO glass and the unannealed AZO/FTO film. As a result, the ZnO nanorod-coated annealed AZO/FTO film demonstrated superhydrophobicity, high transparency and low reflectance in the visible range. Also this film had the lowest sheet resistance of 4.0 Ω/sq, implying its good electrical conductivity. This investigation provides a valuable reference for developing multifunctional transparent conductive films. [ABSTRACT FROM AUTHOR]

Variant selection in laser melting deposited (LMD) α + β titanium alloy (TC21) was investigated using linear thermal expansion and EBSD test. At micro level, volume change of lattice is anisotropic during solid phase transformation in titanium alloy. If several variants are more abundant than others, the anisotropic volume changes could be observed at macro level. In linear thermal expansion test, the growth directions of as-deposited and α + β treated LMD TC21 alloy expanded during α→β phase transformation while at the transverse direction, a contraction was observed. The β treated alloy showed isotropic expansion in the same temperature region. Anisotropic volume changes of as-deposited and α + β treated LMD TC21 alloy confirmed the variant selection happened in deposition process. During depositions, the anisotropic internal thermal stress generated in the as-solidified metal before solid phase transformations started. The existed thermal stress made the lattice spacing a little distorted. The anisotropic distortion of lattice spacing led to the variant selection. The theoretical analysis was supported by EBSD results. [ABSTRACT FROM AUTHOR]

Mg 2− x Cu x SiO 4 (0 ≤ x ≤ 0.2) ceramics were fabricated by the traditional solid-state process. The results revealed that solid solution was formed at x ≤ 0.2 by substitution Cu 2+ for Mg 2+ and the sintering temperature was lowered from 1500 to 1200 °C. LiF-doped (1 − y )Mg 1.9 Cu 0.1 SiO 4 – y (La 0.5 Na 0.5 )TiO 3 (0.1 ≤ y ≤ 0.4) composite ceramics were obtained at a temperature range from 890 to 1000 °C. As increasing (La 0.5 Na 0.5 )TiO 3 content y , the τ f values showed a continuous positive increase. The 0.8Mg 1.9 Cu 0.1 SiO 4 –0.2(La 0.5 Na 0.5 )TiO 3 composite ceramics with 4.0 wt% LiF sintered at 950 °C possess excellent microwave dielectric properties of ε r = 13.3, Q × f = 14,400 GHz, and τ f = 6 ppm/°C. [ABSTRACT FROM AUTHOR]

The α/α interfaces caused by the nucleation and growth of secondary α (α s ) phase in laser melting deposited (LMD) TC21 titanium alloy were investigated by SEM, TEM and EBSD. There were two kinds of α s phases in conventionally heat treated LMD TC21 alloy, regular α s phase and irregular α s phase. The regular α s nucleated through surface instability and the protuberance of α p phase and spread into β matrix with a plate like shape while the irregular α s phase nucleated at the defects of β matrix. A gradient orientation region between α s phase and α p phase was made after nucleation and growth of regular α s phase. When different α s phases met each other, small-angle α s /α s interfaces were made, as a result of misorientation. These interfaces were made up by a series of dislocations. Large-angle α s /α s interfaces which were caused by twinning, although not observed, were confirmed in theory. After aging treatment, the α s /α s interfaces disappeared as a result of diffusional reaction. [ABSTRACT FROM AUTHOR]

Aurivillius single-phase Bi 3.5 La 0.5 Ti 2 Nb 0.5 Fe 0.5 O 12 ceramics was synthesized by solid state reaction route. The ac data in terms of dielectric and impedance were collected to probe the dielectric relaxation behaviors in the ceramics. Two relaxations were distinguished and determined to originate from grains and grain boundaries, respectively, by the combination of impedance and electric modulus analysis. A phase transition was observed to take place at ∼440 °C. The possible relaxation-conduction mechanisms were discussed on the basis of kinetic analyses of dielectric data. This work elucidated the contributions of microstructures and defects to the relaxations and conduction. It is significant for correct understanding of electrical properties of Bi 3.5 La 0.5 Ti 2 Nb 0.5 Fe 0.5 O 12 related ceramics and consequent modification of process to improve the performance of ceramics. [ABSTRACT FROM AUTHOR]

A two-step strategy, i.e. sputtering Ni layers on FTO glass combined with magnetic-field-assisted laser irradiation, was proposed to prepare laser-textured Ni/FTO bilayer composite films. By analyzing surface morphology, crystal structure and photoelectric properties of Ni/FTO films with different Ni layer thicknesses, the Ni/FTO film with a 10-nm-thick Ni layer (Ni 10 /FTO film), which had the best overall photoelectric property, was chosen to undergo magnetic-field-assisted laser irradiation with different laser fluences. Magnetic-field-free laser irradiation of the Ni 10 /FTO film was also carried out for comparison purpose. It was found that magnetic-field-assisted laser irradiation using a fluence of 1.0 J/cm 2 was more effective for simultaneously achieving texturing and annealing, resulting in formation of ideal grating textures and significantly increased grain size. The corresponding film (MLI-NF1.0 film) showed the highest figure of merit of 22.8 × 10 −3 Ω −1 compared to 13.1 × 10 −3 Ω −1 of the FTO glass and 1.4 × 10 −3 Ω −1 of the Ni 10 /FTO film, suggesting that the two-step strategy is excellent for preparing textured Ni/FTO films with high photoelectric properties. [ABSTRACT FROM AUTHOR]

In Faraday supercapacitors, battery-type materials despite their high theoretical capacity have not shown prospect yet in application primarily due to their especially low cycling stability (< 10,000 cycles), sharp contrast to the carbon materials in electrical double layer capacitors (>> 100,000 cycles). The so far materials structure-stabilizing strategies, established on the acknowledged structure-destabilizing mechanism under electrochemical stress, seem not significantly effective or practical. Actually, the misunderstanding on structure-destabilizing mechanism leads to the slow progress of battery-type materials in application. In this work, the intrinsic structure-destabilizing mechanism is revealed as the agglomeration of materials originating from their dissolution-recrystallization behavior instead of from electrochemical stress. Based on the as-proposed mechanism, a rod-like micro-nano architecture with a thin carbonaceous shell is designed and built deliberately for Ni(OH) 2 notorious in its especially low stability as a demonstration for stabilizing the structure of battery-type materials. The carbonaceous shell blocks the interflow of dissolved species between Ni(OH) 2 rods, significantly reducing their agglomeration. This structure-stabilizing effect enables Ni(OH) 2 ultra-long cycling life of > 100,000 cycles, thus verifying the as-proposed structure-destabilizing mechanism. The positive results in this work suggest that the significance of battery-type materials in supercapacitors should be revalued. [Display omitted] • The structure-destabilizing mechanism of battery-type materials is revealed. • A rod-like micro-nano architecture with a thin carbonaceous shell is designed. • The micro-nano architecture has ultra-long cycling life of > 100,000 cycles. [ABSTRACT FROM AUTHOR]

Aluminium (Al), silver (Ag) and copper (Cu) layers were deposited on commercial fluorine-doped tin oxide (FTO) glass by direct current (DC) magnetron sputtering, so as to form Al/FTO, Ag/FTO and Cu/FTO bilayer films. Then all the as-deposited metal/FTO films were irradiated using a 532 nm nanosecond pulsed laser with a fluences of 1.05 J/cm 2 . X-ray diffraction (XRD) analysis confirmed that all the laser-irradiated films were annealed by the laser and showed increased average crystallite size in FTO layers. Laser-induced grating structures were also obtained on the surfaces of the laser-irradiated Ag/FTO and Cu/FTO films, resulting in higher surface roughnesses and average transmittances of the films. But due to the broken continuity of the Ag and Cu layers, the sheet resistances of these two films slightly decreased as compared to that of the laser-irradiated Al/FTO film. It was also found that the laser-irradiated Ag/FTO film, whose average transmittance in 400–800 nm waveband and sheet resistance was 81.5% and 6.6 Ω/sq respectively, had the better figure of merit, indicating that the photoelectric property of FTO-based bilayer films could be further optimized through achieving fabrication of laser-induced grating structures and laser annealing in one step. [ABSTRACT FROM AUTHOR]

Abstract: An efficient near infrared (NIR) quantum cutting in CaSc2O4: Tm3+/Yb3+ phosphor has been demonstrated by the visible and NIR spectra properties as well as the decay curves of Tm3+:1G4 level. Upon excitation of Tm3+:1G4 level with a blue photon at 466nm, Yb3+:2F5/2 level can emit two NIR photons around 1000nm through cooperative energy transfer (ET) from Tm3+ to Yb3+ with the maximum energy transfer efficiency is 71%, and highest theoretical quantum efficiency reaches 171%, close to the limit of 200%. Because the energy of Yb3+ transition is matched well with band gap of crystalline silicon, the excellent downconversion luminescence property indicates that CaSc2O4:Tm3+/Yb3+ is a promising oxide material for increasing the conversion efficiency of crystalline silicon solar cells. [Copyright &y& Elsevier]

Highlights: [•] A monodispersed nano-LiFePO4 of regular angularity was synthesized via hydrothermal method. [•] The nano-sized hexahedral LiFePO4 was coated with different carbon sources. [•] The LiFePO4 coated with sucrose precursor exhibits the best power rate performance. [•] Li ion diffusion property is not considerably affected by the used carbon sources. [ABSTRACT FROM AUTHOR]

Abstract: A novel TiO2 double light-scattering layer (TiO2-DLL) film consisting of TiO2 hollow spheres (TiO2-HS) as overlayer and TiO2 nanosheets (TiO2-NS) as underlayer was designed as the photoelectrode of dye-sensitized solar cells (DSSCs). The photoelectric conversion performances of DSSCs based on TiO2-HS film, TiO2-NS film, and TiO2-DLL film were investigated. It was found that the TiO2-DLL film cell achieved the highest conversion efficiency and reached up to a maximum value of 5.08%, which is 23.3% higher than that of TiO2-HS film cell (η =3.62%) and 8.3% higher than that of TiO2-NS film cell (η =4.31%) under identical film thickness at a constant irradiation of 100mWcm−2. The enhanced efficiency of TiO2-DLL film can be attributed to its relatively high specific surface area and enhanced light-scattering capability. Furthermore, the TiO2-NS underlayer ensures good electronic contact between TiO2 film and the F-doped tin oxide (FTO) conducting glass. [Copyright &y& Elsevier]

Highlights: [•] Instead of chemical pure zirconia, natural baddeleyite was used as starting material directly to prepare PSZ. [•] RSM was applied for optimization of the sintering process of CaO-PSZ. [•] The temperature, 1540°C; holding time, 5h; and heating rate, 3°C/min were found to be the optimum conditions to achieve the maximum relative density of CaO-PSZ. [•] The predicted quadratic models were obtained and they fit well with the experimental results. [Copyright &y& Elsevier]

• A shell-strengthened hollow structure of NiCo 2 S 4 is built by a hydrothermal method. • The hollowing process follows an in-situ reaction Ostwald Ripening mechanism. • Rich pores, hollow structure and cobalt ions lead to excellent high-rate performance. • The mechanically strengthened shell of NiCo 2 S 4 prolongs its cycling life. For Faraday supercapacitors, some battery-type electrode materials such as nickel-based materials attract intensive attention by virtue of their high theoretical capacity. However, it is quite difficult for these materials to achieve the satisfied high-rate performance and cycling life concurrently due to the contradiction of their individual requirements to the microscopic structure of materials. In this work, we build a hollow architecture of NiCo 2 S 4 at hydrothermal condition following an in-situ reaction Ostwald Ripening mechanism. The as-prepared NiCo 2 S 4 presents a shell-strengthened hollow structure, satisfying the as-mentioned two requirements: (1) the rich pores in shell and hollow structure plus structural cobalt ions lead to the excellent high-rate performance of NiCo 2 S 4 ; (2) the dense particulate layer in shell with additional mechanical strength prolongs the cycling life of NiCo 2 S 4. Consequently, the asymmetrical supercapacitors assembled with NiCo 2 S 4 as positive electrode material show both high energy and power densities, and excellent cycling stability. [ABSTRACT FROM AUTHOR]

• Cs 2 KGaF 6 :Mn4+ phosphor with high EQE of 43% was systhesized via co-participated methods. • DFT calculation reveals [MnF 6 ]2- occupied [GaF 6 ]3- and produce a V Cs ′ vacancy to balance the charge mismatch. • Unequivalent doping strategy provides detailed insights into the local structure of Mn4+ substituted in fluorides. • Cs 2 KGaF 6 :Mn4+ phosphor is suitable for wide color gamut displays. [Display omitted] Narrow-band red-emitting phosphors are worth investigating and developing to enhance their luminescence efficiency for white light-emitting diodes (WLEDs) and broaden the color gamut of backlight displays. Herein, a novel red-emitting fluoride phosphor Cs 2 KGaF 6 :Mn4+ (CKGFM) was synthesized, which presents sharp red emission bands, short fluorescence lifetime (τ = 3.81 ms) and high external quantum efficiency (EQE = 43%). To better understand Mn4+ incorporation in CKGFM, density functional theory (DFT) energetic calculations were performed to compare the charge compensation probabilities of an Mn4+ substituted at a Ga3+ or K+ site. The temperature-dependent luminescence trend shows that the CKGFM phosphor has good thermal stability in the temperature range of 15–120 ℃, indicating its potential in backlight LEDs. The as-prepared CKGFM phosphor was used to fabricate one white light-emitting diode (WLED) with β-SiAlON:Eu2+ green phosphor and blue InGaN LED chip, which shows a high luminous efficiency of 106.30 lm∙W−1 and a National Television Standards Committee (NTSC) value of 114.6%. The present study provides detailed insights into the local structure of Mn4+ substituted in fluoride red-emitting phosphors and helps to realize better Mn4+ emission for WLEDs. [ABSTRACT FROM AUTHOR]

Abstract: We report on the effect of Mg doping on the thermoelectric properties of p-type BiCuSeO oxyselenide, with layer structure composed of conductive (Cu2Se2)2− layers alternately stacked with insulating (Bi2O2)2+ layers. The substitution of Bi3+ by Mg2+ leads to an enhancement of the electrical conductivity and a decrease of the thermal conductivity. Coupled to high Seebeck coefficients, ZT at 923K is increased from 0.45 for pristine BiCuSeO to 0.67 for Bi0.95Mg0.05CuSeO. However, the efficiency of Mg doping in the insulating (Bi2O2)2+ layer is low, and this doping only leads to a limited increase of the hole carriers concentration. Therefore Mg doped BiCuSeO has relatively low electrical conductivity which makes its thermoelectric figure of merit much lower than that of Ca, Sr and Ba doped BiCuSeO. [Copyright &y& Elsevier]

Abstract: The thermoelectric oxide AgSbO3 has been prepared by the conventional solid state reaction (CSSR) method combined with spark plasma sintering (SPS) technique. The electrical resistivity ρ and the Seebeck coefficient S were measured simultaneously from 323 to 873K. It was found that ρ decreased monotonically from 3.75 to 7.20×10−4 Ωm as the temperature was increased. The highest absolute value of the Seebeck coefficient |S| (S <0) reached 209μVK−1 at 873K. In addition to the large thermopower, a rather low thermal conductivity of 0.825Wm−1 K−1 at 873K has been observed. Better thermoelectric performance at higher temperatures may origin from the change in hybridization of the Ag 4d–O 2p orbital and the Ag 5s–Sb 5s orbital, which are responsible for engineering energy positions and shapes of the valence-band (VB) top and the conduction band (CB) bottom, respectively. [Copyright &y& Elsevier]

A new kind of spherical Fe 3 S 4 with a 3D hierarchical structure, which is constructed with many intercrossed nanorods, is successfully synthesized via a facile hydrothermal method. The achieved Fe 3 S 4 microspheres are evaluated as advanced anode materials for alkaline iron-based secondary batteries for the first time. Influences of hydrothermal temperature on the physical and electrochemical performances of Fe 3 S 4 particles are investigated systematically. It is found that the Fe 3 S 4 fabricated at 150 °C exhibits better electrochemical properties than the ones obtained at other temperatures, including higher discharge capacity, attractive high-rate capability and good cycling stability. At 0.2, 0.4, 1.0, 2.0, and 5.0 C, the Fe 3 S 4 (150 °C) delivers discharge capacity of ~328.5, ~307.6, ~280.5, ~235.9, and ~169.5 mAh g−1, respectively. Especially, after 400 cycles at 1 C/1 C, the Fe 3 S 4 (150 °C) presents capacity retention of 88.61%. The pronounced performance of Fe 3 S 4 is attributable to its inherent electrochemical activity, unique 3D hierarchical structure, and high S content, eventually resulting in the reduced charge transfer resistance, improved reversibility, and a beneficial porous electrode structure during cycling. Therefore, the as-achieved Fe 3 S 4 microspheres are promising anode materials for high-performance alkaline iron-based batteries. • Fe 3 S 4 microspheres are synthesized via a facile hydrothermal approach. • Spherical Fe 3 S 4 is firstly used as anode material for iron-based batteries. • The Fe 3 S 4 (150 °C) exhibits excellent high-rate capability and cycle stability. [ABSTRACT FROM AUTHOR]

Abstract: The thermodynamic assessment is made for the Sb–Zn system using the CALPHAD approach (calculation of phase diagram). The liquid phase, the intermediate compounds of SbZn, Sb3Zn4 (three modifications of ɛ, δ and δ′) and Sb2Zn3 (two modifications of η and ξ) and the terminal phases of rhombohedral-Sb and hcp-Zn are taken into consideration in this optimization. Liquid phase is described by a substitutional solution model with Redlich–Kister polynomials. The intermediate compounds are treated as stoichiometric. Two terminal phases are taken as unary phases according to literature. A set of self-consistent thermodynamic parameters is obtained and the calculated phase diagram and thermodynamic properties are presented and compared with experimental data obtained from literature. [Copyright &y& Elsevier]

Abstract: The phase relation and the structural transition in (1− x)Pb(Mg1/3Nb2/3)O3–xPbTiO3 ceramics for 0.28≤ x ≤0.4 were investigated by high resolution X-ray powder diffraction (HR-XRD), temperature-dependent X-ray powder diffraction (T-XRD) and dielectric analysis. Unexpected broad and frequency dispersive dielectric anomalies were observed, just below the tetragonal (T)–cubic (C) transition dielectric peaks in temperature dependent dielectric permittivity in the unpoled ceramics for x =0.32 and 0.34. Structural analysis revealed that the monoclinic (MB) and tetragonal (T) structures coexisted in the composition range 0.32≤ x ≤0.36 at room temperature and in a wide temperature range for x =0.32 and 0.34, however, in a non-equilibrium state. The sluggish MB–T transition is closely related to the dielectric anomalies. The metastable ferroelectric phase diagram near MPB was re-constructed based on XRD and dielectric analysis. The phase transition procedure was discussed. [Copyright &y& Elsevier]

Abstract: A thermodynamic modeling of Mg-doped p-type GaN was carried out to describe the thermodynamic behaviors of native defects, dopants (Mg and H) and carriers in GaN. The formation energies of charged component compounds in a four-sublattice model were defined as functions of the Fermi-level based on the results of the first-principles calculations and adjusted to fit experimental data. The effect of the solubility of Mg on the low doping efficiency of Mg in GaN and the role of H in the Mg-doping MOCVD process were discussed. The modeling provides a thermodynamic approach to understand the doping process of GaN semiconductors. [Copyright &y& Elsevier]

A thermodynamic assessment of the binary Ga–Ti system was performed based on the evaluation of the literature and our experimental results. Diffusion couple and alloy samples with appropriate compositions were prepared and analyzed by electron probe microanalysis and X-ray diffraction to determine the stability of intermetallic compounds. The Ga-rich part of phase diagram was checked by differential thermal analyses. The subreguler solution model was used to describe the solution phases liquid (L), b.c.c. (β), h.c.p. (α1) and f.c.c. (γ1). The compound energy model was employed to describe compounds with homogeneity ranges of Ti3Ga (α2), Ti5Ga4(ρ) and TiGa(γ2). The compounds Ti2Ga, Ti5Ga3, Ti2Ga3, TiGa2 and TiGa3 were treated as stoichiometric phases. A set of thermodynamic parameters was obtained and the calculated phase diagram was presented. [Copyright &y& Elsevier]

In this work, we choose NiO as an example of battery-type materials. We reveal that the electrochemical destabilization of NiO is attributed to the particle merging caused by electrochemical Ostwald ripening. Based on this understanding, we construct a particulate NiO-composed 2D structure coated by a thin carbon layer. Due to the prevention of particle merging by carbon coating and the increase of electrical and ionic conductivities by oxygen vacancies, this structure presents high electrochemical performance and an ultra-long cycling life. This carbon-coated 2D structure of NiO has a high specific capacity of 437.8 C g−1 at low current density and presents excellent high-rate performance (capacity retention of 66% at high current density). It exhibits ultra-high electrochemical stability (capacity retention of 93.5% after an ultra-long cycling of 100,000 cycles). This work demonstrates the success of carbon modification strategy for NiO, also may provide a significant outlet for transforming low-performance battery-type materials into high-performance materials. [Display omitted] • A particulate NiO-composed 2D structure coated by a thin carbon layer was prepared. • The NiO particle merging is caused by the electrochemical Ostwald ripening. • The Ostwald ripening is inhibited by the carbon coating. • Oxygen vacancies increase the electrical and ionic conductivity of NiO. • The 2D structure of NiO presents high performance and ultralong cycling life. [ABSTRACT FROM AUTHOR]

In this study, Al-Si-Mg composites were prepared by adding different combinations of titanium (Ti), zirconium (Zr), boron (B), and antimony (Sb)，and its micro-structure and mechanical properties were investigated. The results revealed that the average diameter of α-Al grains in the novel alloy, prepared through the combined addition of Ti, Zr, B, and Sb, was 110 µm, with a secondary dendritic arm spacing (SDAS) of 22.4 µm. This grain refinement is attributed to the in-situ formation of heterogeneous nucleation sites L12-(Al, Si) 3 (Ti, Zr). The alloy heat-treated at T6 exhibited notable mechanical characteristics, including a tensile strength of 354.5 MPa, a yield strength of 317.9 MPa, and an elongation at break of 5.6%. Significantly, the enhancement in mechanical properties is found to be independent of the modifications of eutectic silicon. This improved strength and elongation are attributed to both grain refinement and the in-situ formation of I4-(Al, Si) 3 (Ti, Zr). Overall, these findings provide an effective and direct method for obtaining high-performance Al-Si-Mg composites. • Remarkable grain size refinement of α-Al in composites. • T6 heat treatment favors the precipitation of Mg 2 Si phases and nanoscale I4-(Al, Si) 3 (Ti, Zr) phases. • T6 heat-treated composites exhibit excellent mechanical properties. [ABSTRACT FROM AUTHOR]

Newly developed functional materials for energy storage have attracted considerable attention because of rapidly increasing global energy consumption and environmental problems. In this study, a polycyclic aromatic hydrocarbon, perylene-3,4,9,10-tetracarboxylic dianhydride was used as a precursor to a three-dimensional (3D) carbon sponge (CS). Subsequently, the sea urchin-like cobalt-nickel carbonate hydroxide (NiCo–CH) was anchored on CS by a hydrothermal method, using urea as a stabilizer and alkali source. The obtained CS/NiCo–CH composite demonstrated excellent electrochemical performance with a specific capacitance of 643 F g−1 (1 A g−1) and outstanding cycle stability (84.2% of the initial capacitance was retained after 3000 charge/discharge cycles). In addition, an asymmetric supercapacitor constructed using CS/NiCo–CH and activated carbon as positive and negative electrodes, respectively, exhibited a high specific capacitance of 131.6 F g−1 at 1 A g−1 and high energy density of 38.4 Wh kg−1 at 724.1 W kg−1. The proposed CS/NiCo–CH composite may be used for electrochemical energy storage. • Sea urchin-like cobalt-nickel carbonate hydroxide was anchored on carbon sponge by simple hydrothermal method. • CS/NiCo–CH composite demonstrates excellent electrochemical performance. • Supercapacitor power density of 724.1 W kg−1 at energy density of 38.4 Wh kg−1. [ABSTRACT FROM AUTHOR]

Simple methods for the collection and transportation of water droplets can solve complex problems, but developing technologies to achieve this is a challenge. To this end, widespread attention in recent years has focused on the preparation and application of superhydrophobic surfaces. Inspired by the structures of trichomes (hairs) of Sarracenia , a genus of carnivorous pitcher plants, we report a bionic high-low rib-like microstructure with superhydrophobic and directional water transport properties. At the same time, we can accelerate fog-collection efficiency by preparing a surface enabling directional slip of liquid. This work provides a good strategy for liquid transportation and fog collection, which has broad application prospects in the collection of rainwater in desert areas and the transmission of microfluidics in mechanical engineering. • A bionic high-low rib-like micro structure with super-hydrophobic. • The contact angle of the sample can reach as high as 160°. • This surface is hydrophobic in dry state and collects water in wet state. [ABSTRACT FROM AUTHOR]

Two variants of 14-Cr oxide dispersion strengthened FeCrAl alloys are fabricated by MA method. The morphology, phase and oxide/matrix interface structure of the nano-oxide dispersoids in both alloys are characterized by TEM, HRTEM, TKD and XRD. Almost all the small precipitates in Fe–14Cr-4.5Al–2W-0.4Ti-0.4Y alloy are identified as orthorhombic YAlO 3 particles. In Fe–14Cr-4.5Al–2W-0.4Ti-0.3Zr-0.4Y ODS alloy, Y 2 (Zr 0.4 Ti 0.6) 2 O 7 particle with better coherent relationship with the matrix is found. Almost 23% Y 2 (Zr 0.4 Ti 0.6) 2 O 7 and YAlO 3 particles coexist, resulting in refinement of average diameter of oxide dispersoids and improvement of mechanical strength. Tensile tests from room temperature to 1000 °C demonstrate the attainment of strength-toughness matching in these ODS FeCrAl alloys. The intergranular fracture after the tensile tests at elevated temperature indicates that grain boundary sliding may be the dominant mechanism for deformation. • Two ODS FeCrAl alloys with uniformly distributed nano-oxide particles, and excellent mechanical properties were fabricated. • Y 2 (Zr 0.6 Ti 0.4) 2 O 7 nanoparticles were identified in Zr-addition ODS FeCrAl alloy, having good coherency with matrix. • Dislocation density was proportional to the amount of oxide dispersoids in ODS FeCrAl alloys during mechanical processing. • Grain boundary sliding may be the dominant mechanism for deformation at elevated temperature (≥1000 ℃). [ABSTRACT FROM AUTHOR]

Typical synthesis of α″-Fe 16 N 2 nanoparticles involves nitridation of iron nanoparticles obtained from the reduction of iron oxide, during which the iron nanoparticles are prone to agglomerate and make the nitridation difficult. Herein, we report a method to obtain α″-Fe 16 N 2 phase by loading the iron oxide (hematite, α-Fe 2 O 3) precursors in the channels of the ordered mesoporous silica (SBA-15), and the α-Fe 2 O 3 /SBA-15 was prepared by means of a facile impregnation and calcination method. The results showed that the nitridation efficiency was greatly improved than previous reports and high α″-Fe 16 N 2 content (∼92 wt%) was synthesized at 160 °C for 8 h. Transmission electron microscopy and N 2 adsorption-desorption characterizations demonstrate that the as-synthesized α″-Fe 16 N 2 /SBA-15 nanocomposites maintained the ordered hexagonal mesoporous structures, and α″-Fe 16 N 2 was successfully filled inside the mesochannels of SBA-15, indicating the SBA-15 has taken great effect in the remarkable increasement of nitridation efficiency. Image 1 • High-purity α″-Fe 16 N 2 (∼92 wt.%) was successfully synthesized at 160 °C for 8 h via a template-assisted method. • The nitridation efficiency of α″-Fe 16 N 2 was greatly improved than previous reports. • The α″-Fe 16 N 2 /SBA-15 maintained the ordered hexagonal mesoporous structures, and Fe 16 N 2 was filled inside the mesochannels of SBA-15. • The magnetization and coercivity of the α″-Fe 16 N 2 measured under 20 kOe are 233 emu/g and 1.67 kOe, respectively. [ABSTRACT FROM AUTHOR]