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This work proposes an effective design of bioactive 3D-printed Ti-6Al-4V scaffold with the CaO-MgO-SiO 2 glass-ceramic coating to realize a comparable elastic modulus of bone tissue and boost osteogenic differentiation. The improved elastic modulus and stiffness of Ti alloy were achieved via effectively increasing surface area of Ti alloy to reduce stress shielding effect. A hydrophilic surface and bioactive glass-ceramic coating were conducted via chemical etching and heat-treatment under argon atmosphere to enhance cells attachment and boost cell proliferation and osteogenic differentiation. The expression of osteogenic genes in bioactive CaO-MgO-SiO 2 glass-ceramic was evaluated through ALP, OPN, Runx2, and Col1A1 gene markers to explore the mechanism of superior osteogenic differentiation. Significant increase in OPN expression level confirmed the effect of CaO-MgO-SiO 2 coating for the enhancement of osteogenic bioactivity. This work provides a feasible approach through surface etching and bioactive CaO-MgO-SiO 2 glass-ceramic coating on the Ti alloy surface to enhance bioactivity and osteogenesis. [Display omitted] • A compatible bone tissue of 3D-printed Ti-6Al-4V scaffold with the novel bioactive CaO-MgO-SiO 2 glass-ceramic coating. • A superior surface modification to enhance cells attachment and boost cell proliferation and osteogenic differentiation. • This work provides a feasible approach on the Ti-alloy surface to enhance bioactivity and osteogenesis. [ABSTRACT FROM AUTHOR]

The Cu-4Sn and Cu-4Sn-0.15P alloys with rod diameter of 12.5 mm were prepared and then cold drawn to 2.6 mm via multi-pass drawing. The microstructure evolutions, mechanical properties, and electrical conductivity of Cu-4Sn and Cu-4Sn-0.15P alloys were comprehensively analyzed using optical microscope, scanning electron microscope, tension test and electrical conductivity tester. As compared with the P-free alloy, the addition of P can form a new kind of P-rich phase in the Cu-4Sn alloy, and thus refine the casting microstructure via pinning the grain boundary. The toughening mechanisms of P-rich phases in Cu-4Sn-P alloy wires during cold drawing were investigated. With accumulative drawing strain, the spherical P-rich phase gradually changes into fibrous phases, which thus introduce obvious fiber reinforced strengthening. In addition, the distribution of P-rich phase also enhances the< 111 > texture, and promotes the growth of fragmentation zone. It contributes to an improved ultimate tensile strength and final elongation from 664.5 MPa and ∼ 0 % in Cu-4Sn alloy to 970.5 MPa and 1.53 % in Cu-4Sn-0.15P alloy. Finally, the conductivity for Cu-4Sn-0.15P decreases slightly owing to the intensified electron scattering with high amount of primary phase after the addition of P element. • Adding P to Cu-Sn alloy results in more uniform grain size, while increasing dendrite segregation. • Cu-4Sn-0.15 P alloy wire present more homogeneous distribution of P-rich phases with P content of 9 wt%. • Spherical P-rich phases evolve into fibrous shapes, contributing to higher strength and better elongation. • The addition of P increases the proportion of grain fragmentation during drawing. [ABSTRACT FROM AUTHOR]

Novel one-dimensional (1D) magnetic flower-like CoFe 2 O 4 @Bi 2 WO 6 @BiOBr composite photocatalysts were prepared by electrostatic spinning techniques, calcination, solvothermal and precipitation methods. The microscopic morphology and the structure of the photocatalysts were characterized using XRD, SEM, XPS and BET. The photocatalytic efficiency of the photocatalysts was evaluated by measuring the degradation rate of rhodamine B (RhB). The results showed that the efficiency of CoFe 2 O 4 @Bi 2 WO 6 @BiOBr for 3 h is 92.08%. After three cycles, the value remained at 77.71%, showing excellent photocatalytic stability. Furthermore, the possible mechanism of photocatalytic degradation process was proposed by radical trapping experiment and PL test. This work designed and prepared a prospective photocatalyst for degrading organic matters of water environments. • CoFe 2 O 4 was designed as 1D structure to realize the separation and axial transport of photogenerated charges. • CoFe 2 O 4 as the magnetic core facilitated the recycling of the photocatalyst. • Bi 2 WO 6 was designed as flower-like structure to obtain a larger surface area. • BiOBr was combined with Bi 2 WO 6 to construct a heterojunction. [ABSTRACT FROM AUTHOR]

A novel Tm3+: CaY 0.65 Gd 0.35 AlO 4 (Tm3+: CYGA) disordered crystal was successfully grown for the first time, to the best of our knowledge, using the Czochralski method. The optical properties and laser performance were investigated in details. Owing to the addition of Gd3+ ions to the Tm3+: CYA crystal, the Tm3+: CYGA crystal possesses a wider Tm3+ absorption and emission spectra compared with those of the Tm3+: CYA and Tm3+: CGA crystals. In particular, the full width at half-maximum (FWHM) of the emission spectra at approximately 2 µm for the Tm3+: CYGA crystal was 221.3 nm, which is larger than those of the Tm3+: CYA (200 nm) and Tm3+: CGA (151 nm) crystals. Furthermore, an efficient laser operation of the Tm3+: CYGA crystal at 1974 nm was achieved for the first time, with a slope efficiency of up to 31.5 %, corresponding to a maximum output power of 810 mW. The results show that Tm3+: CYGA disordered crystals have the potential to be applied in ∼ 2-μm broadband tunable lasers and ultra-short pulse lasers. [Display omitted] • A novel Tm3+: CaY 0.65 Gd 0.35 AlO 4 (Tm3+: CYGA) disordered crystal has been successfully grown for the first time. • The Tm3+ absorption and emission spectrum has been effectively broadened with the addition of Gd3+. • An efficient laser operation of Tm3+: CYGA crystal at 1974 nm was achieved for the first time. • Tm3+: CYGA crystal could be a promising disordered laser host for ∼ 2 µm broadband tunable laser and ultra-short pulse laser [ABSTRACT FROM AUTHOR]

Donor-π bridge-acceptor (D-π-A) design principle has been widely employed to build functionalized materials with excellent optical properties, whereas its feasibility in electrocatalytic reactions is seldom investigated. We demonstrate the primary study of D-π-A rule in constructing electrocatalysts for oxygen reduction reaction (ORR) purpose by rationally designing three cobalt porphyrins EGZ1–3 with 9H-carbazole, triphenylamine and N,N-diphenyl-[1,1′-biphenyl]-4-amine as the donor substituents, respectively, cobalt porphyrin as the π bridge, and cyanoacrylic acid as the acceptor unit. The electronic properties of the molecules are calculated using the density functional theory and the composite catalysts EGZs/C are characterized by a series of spectroscopic approaches. The electrochemical measurements show that EGZ3/C attains a more positive reduction potential and a greater response current density than EGZ1/C and EGZ2/C, which is possibly due to the optimized electronic structure and the substituent effect. The electron transfer number as well as hydrogen peroxide generation yield values suggest slightly better selectivity of EGZ3/C and EGZ2/C than those of EGZ1/C (i.e., ~ 2.9, ~ 2.9 vs. ~ 2.7 and ~ 54%, ~ 53% vs. ~ 62%, respectively) towards full oxygen reduction. Our result reveals the feasibility of the D-π-A design rule and the importance of molecular electronic state and the substituent feature in constructing ORR electrocatalysts. [Display omitted] • Three donor-π-acceptor cobalt porphyrins are synthesized. • The electronic structure of porphyrins is calculated by density functional theory. • Porphyrin-carbon black composites are studied in oxygen reduction reaction. • The electrocatalyst EGZ3/C attains the best ORR performance. • Both electronic structure and substituents affect the electrocatalytic activity. [ABSTRACT FROM AUTHOR]

• Triphenylamine-porphyrin dyads are synthesized for photocatalysis. • XZP2/TiO 2 exhibits the most efficient charge separation as photoelectrode. • XZP2/TiO 2 performs the best in photodegradation of acid black and tetracycline. • Photocatalytic mechanism and interfacial charge transfer pathways are proposed. [Display omitted] Three triphenylamine (TPA) substituted dichromophoric zinc porphyrins XZP1–3 and a single zinc porphyrin ZP1 have been rationally designed to construct dye-sensitized TiO 2 nanoparticles to explore the feasibility of dichromophoric dye design for photocatalysis. TPA, N,N -diphenyl-(1,1′-biphenyl)− 4-amine and a carbazole-diphenylaniline derivative are attached to the meso -position of porphyrin core as the second chromophore. The electronic structure of the porphyrins is studied by density functional theory (DFT) calculations and the dye-sensitized composites are investigated using couples of spectral and electrochemical techniques. XZP2/TiO 2 exhibits the smallest charge transfer resistance and the longest electron lifetime among the investigated composites. The same catalyst performs the highest efficiency in photodegradation of both acid black (AB1) and tetracycline (TC) polluted water samples. Electronic paramagnetic resonance and radical quenching experiments reveal that the priority reactive species are superoxide radicals (•O 2 −) and holes (h+), suggesting the efficient charge separation at the porphyrin-sensitized TiO 2 interface. This work demonstrates the facilitated interfacial charge separation using dichromophoric dye-sensitized semiconductor particles for photodegradation and, the insights should aid in dyad design for photocatalysis application. [ABSTRACT FROM AUTHOR]

With the seriously environmental pollution, photocatalytic technology has been extensively studied for ensuring the continuous development of society. As a type of appealing semiconductor, bismuth-based materials have become a research hotspot in the field of photocatalysis due to their unique electronic structure, appropriate bandgap energy, high light quantum and outstanding electronic transmission efficiency. However, the separation and recovery of photocatalyst from reaction systems is difficult. The most promising strategy to facilitate separation process is to introduce a magnetic component. This review has mainly involved a classification, current challenges and prospects on the recent progress in fabrication of magnetic bismuth-based photocatalytic materials, as well as the list of their degrade object, dosage, initial concentration and reaction time. [ABSTRACT FROM AUTHOR]

• A single host whit emitting phosphor Ca 3 (SiO 3) 3 :Eu2+, Mn2+ is monodispersed and uniform spherical particles. • The samples are monodispersed and uniform spherical particles with a diameter about 700 nm. • The nonradioactive energy transfer from the lowest 5d levels of Eu2+ to 3d excited levels of Mn2+ was efficient. Eu2+ ions were excited by UV LEDs chip and transmitted energy to Mn2+ ions, then emitted white light. • The color-rendering index and high correlated color temperature of Ca 3 (SiO 3) 3 :Eu2+, Mn2+ x can be adjusted by simply changing the concentration of Eu2+ and Mn2+. A single host phosphor Ca 3 (SiO 3) 3 :Eu2+, Mn2+ (CSO: Eu2+, Mn2+) with good monodispersity has been synthesized by high temperature solid state reaction combined with precursor, using porous silica as template and raw material. The phase, size and surface morphology of the phosphor were measured by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Luminescence properties were characterized by photoluminescence excitation (PLE) and emission spectra from room temperature to 480 K. CSO: Eu2+ has strong excitation band in UV region and emits blue light. To compensate for the lack of orange-red emission region and avoid using multiple phosphors, Mn2+ ions are introduced into the Ca2+ sites. The remarkable enhancements of the orange band attributed to an efficient nonradioactive energy transfer from Eu2+ to Mn2+, which has been testified by the photoluminescence spectra and fluorescence decay dynamics. The emitting light of Eu2+, Mn2+ co-doped CSO could be modulated from cool white to warm white by changing the molar ratio of Eu2+ and Mn2+. [ABSTRACT FROM AUTHOR]

Piezo-catalysis represents a promising and environmentally-friendly technology for dye degradation, but the commonly used BaTiO 3 piezoelectric material still face bottleneck of relative low piezo-catalytic activity. Enhancement of its catalytic activity via diversified means is crucial for improving the degradation efficiency and implementation of water treatment. In this study, we synthesized Ba 1- x Sr x TiO 3 nanoparticles utilizing the sol-gel method. The highest catalytic performance for degrading rhodamine B is at x = 0.15 through the piezo-photocatalytic synergy, displaying a degradation rate of 92.66 % within 18 min and an impressive reaction rate of 14.26 × 10−2 min−1, surpassing most of other BaTiO 3 -based materials. Importantly, the nanoparticles exhibited excellent catalytic degradation performance for a variety of pollutants under different environments. In addition, it is confirmed that Sr2+ doping can enhance the catalytic efficiency via three pathways, i.e. modifying energy band gap, modulating grain size as well as Curie temperature. This work provides a convenient strategy for the rational regulation of catalytic performance in BaTiO 3 -based piezoelectric materials. [Display omitted] • Sr-doping in BaTiO 3 for simultaneous regulation of grain size, T c and energy band. • Piezo-photocatalysis achieves stronger synergic effect than single catalysis. • Various mechanisms work together to improve the catalytic performance. • Maintaining high catalytic activity in various conditions for practical applications. [ABSTRACT FROM AUTHOR]

In the Co/Cu-ZIF/Fe 2 O 3 p-n junction, the electrons flow from n-type Fe 2 O 3 to p-type bimetallic Co/Cu-ZIF, resulting in the band bending and inner electric field from positive Fe 2 O 3 to negative Co/Cu-ZIF. The density function theory calculation uncovered that such an electronic property change could boost the water oxidation performance. Experiments reveal that the obtained Co/Cu-ZIF(1/1)/Fe 2 O 3 heterojunction achieves a low overpotential of 273 mV and a small Tafel slope of 133.6 mV·dec-1 at 10 mA·cm-2 current density, which are significantly lower than that of monometallic Co-ZIF and FC substrate. Moreover, the p-n conjunction can promote the electrocatalytic degradation of 4-nitrophenol, and the removal rate reaches 80%, current efficiency (23.97%) and low energy consumption (79.5 Wh·L-1) at 50 mA·cm-2. Therefore, it is expected that MOFs-based p-n conjunction with modulation of electron configuration is a promising alternative to boost the electrochemical water oxidation. [Display omitted] • The monolithic electrode of Co/Cu-ZIF/Fe 2 O 3 p-n junction integrated OER and oxidation of 4-NP. • The doping of second Cu center induced the high-valence Co3+ active sites and the O-containing intermediates. • The band bending and Co3+ led to charge redistribution and electron transfer, boosting the electrocatalytic activities. [ABSTRACT FROM AUTHOR]

• The radii of the nanoscale precipitates are dramatically smaller in the annealed Cu-2Ag-0.14La alloy than in the annealed Cu-2Ag alloy. • The grain size of annealed Cu-2Ag-0.14La alloy is always smaller than that of the annealed Cu-2Ag alloy from 400 °C to 650 °C. • Precipitation strengthening of nanoscale precipitates in the matrix and grain-boundary strengthening during grain refinement substantially improve the yield strength of the Cu-2Ag-0.14La alloy. [Display omitted] A new Cu–2Ag–0.14La alloy is developed to enhance the mechanical property and electrical conductivity with inducement of Ag-rich primary phases and finer nanoscale Ag precipitates. The microstructural evolution and mechanical properties of Cu–2Ag–0.14La and Cu–2Ag alloys obtained by drawing and annealing were then summarized and analyzed. The results indicate that both the yielding and ultimate tensile strengths of annealed Cu–2Ag-0.14La alloy were reinforced after La modification. The average grain sizes of two alloys increase during annealing, but the size ratio (R Cu-2Ag-0.14La /R Cu-2Ag) dramatically varies with rising the heat temperature, evolving from 70.48% at 400 °C to 43.78% at 650 °C. Meanwhile, it is found that the refined grains sizes in Cu-2Ag-0.14La alloy are closely related to the nano-scale precipitates (~450 nm), which hinder the formation of subgrain boundaries at 400 °C, and impose a stronger pinning effect on boundary migration of recrystallized grains during annealing (≥ 450 °C). Consequently, higher hardness and electrical conductivity are contributed by grain refinement and dispersion strengthening of the nanosized phases. [ABSTRACT FROM AUTHOR]

Metallic lithium (Li) is considered to be one of the most promising anodes for Li-ion batteries due to its high theoretical capacity and low reduction potential. However, dendritic growth and substantial volume variations during battery operation make it difficult for commercialization. Here, a graphene and SiO 2 composites material was presented as a lithiophilic host to enable superior long-term cycling for Li-metal anode. The porous skeleton of graphene with excellent electronic conductivity can effectively reduce the actual current density and suppress the volume expansion. And the SiO 2 particles with excellent ionic conductivity can significantly suppress the growth of Li dendrites and regulate the nucleation sites. So doping SiO 2 nanoparticles between graphene sheets can significantly suppress the growth of Li dendrites and the volume expansion effect of metallic Li deposition, while also providing good electrochemical performance. Benefitting from these synergistic effects, the Li-GF@SiO 2 battery exhibits excellent electrochemical reversibility over 500 cycles depositing 1 mAh cm−2 of metallic Li at a current density of 1 mA cm−2, and the coulombic efficiency of the Li-GF@SiO 2 battery is still as high as 97%, but the Li-Cu battery decays after 75 cycles. So this hierarchical SiO 2 -microsphere-graphene host demonstrates great potential for Li batteries. • The type of graphene and SiO 2 composite material is designed for the stable host of lithium (Li) metal anode because of its lithiophilic character. • The hierarchical silica spheres can effectively reduce the actual current density and guide the nucleation of Li metal. • The superior electronic conductivity and ionic conductivity of composite materials are utilized to suppress the growth of Li dendrites and volume expansion. • The novelty lithiophilic host of Li metal anode can achieve over 500 cycles at a current density of 1 mA cm−2 for Li-metal batteries. [ABSTRACT FROM AUTHOR]

The cyclic stability of hydrogen absorption and desorption is an important indicator of hydrogen storage alloy. The decay mechanism was roundly investigated by controlling the depth of dehydrogenation (DOD) of the V 40 Ti 25.5 Cr 26.5 Fe 8 alloy during the process of hydrogen ab/desorption cycles. The V 40 Ti 25.5 Cr 26.5 Fe 8 alloy exhibits the hydrogen desorption capacity of 2.36 wt% at 323 K in the first cycle. After 30 cycles, the decay rate of the hydrogen desorption capacity is only 4.37 % at 40 % DOD, but rises to 8.74 % at 100 % DOD. The hydrogen desorption capacity (C), plateau pressure (P) and micro-strains (S) all show an "acceleration followed by slowing" exponential variation trend with the increase of cycle number (x). Additionally, any two of C , P and S show linear correlation. It is considered that the micro-strains in the crystal lattice is the main factor for the decay of the hydrogen desorption capacity and the plateau pressure. On the premise of ensuring the valid hydrogen storage capacity to meet the requirements of the application, properly reducing DOD per cycle can effectively reduce the micro-strains accumulation and cell volume expansion, thus improving the cyclic stability of the alloy. Moreover, the application of this alloy in a fuel cell bicycle was investigated, and the total range and mileage per unit weight of the alloy are up to 100.8 km and 15.7 km/kg, respectively. Compared with the lead-acid battery, lithium-ion battery and LaNi 5 -based hydrogen fuel cell, the V-Ti-Cr-Fe-based fuel cell shows significant advantages. ● A bran-new method was proposed to slow down the decay of the dehydrogenation capacity of the V 40 Ti 25.5 Cr 26.5 Fe 8 alloy. ● The alloy decay rate of the dehydrogenation capacity is only 4.37% after 30 cycles at 40% DOD, only half that at 100% DOD. ● Six functions were proposed to explain the influences of the micro-strains in the lattice. ● This alloy fuel cell shows significant advantages compared with other batteries through application in a fuel cell bicycle. [ABSTRACT FROM AUTHOR]

It has been a hot research topic to look for inexpensive alternative oxygen evolution reaction (OER) catalysts to replace noble metal-based materials due to their scarcity. Transition metals are ideal candidates because of their high abundance, impressive activities, and easy accessibility. However, a facile method leading to improved performance and stability is still needed. Herein, a highly efficient carbon-encapsulated bimetal catalyst derived from Ni-based metal-organic-frameworks (MOF) was successfully prepared through the low-temperature (350 ℃) pyrolysis of Prussian blue analogue (PBA) precursors under H 2 /Ar atmosphere. Cube-structured PBA as template and precursor，parameters during the pyrolysis process including temperature and calcination atmosphere can be tuned to control the structure and properties of the catalysts. Benefiting from the porous three-dimensional (3D) cubic structure and abundant defect-rich amorphous N-doped carbon shell, Ni 3 Fe@NC-350 exhibits excellent OER activity. The as-prepared catalysts exhibited excellent catalytic performance for OER in 1.0 M KOH with an overpotential of 237 mV to achieve 10 mA cm−2. More importantly, the presented catalyst has an extremely good durability. • A simple low-temperature annealing method was developed to produce alloy encapsulated with N-doping carbon. • The NiFe PBA was employed as nitrogen and carbon source. • The increased activity of OER is due to the synergy of Ni 3 Fe alloy and N-doped carbon layer. • Theoretical calculations revealed that the synergistic effect of NiFe alloy nanoparticles and N-doped carbon layer. [ABSTRACT FROM AUTHOR]