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The transparent [Li 0.04 (K 0.5 Na 0.5) 0.96 ]NbO 3 +0.5mol% Er 2 O 3 (KNNLN-Er) lead-free piezoelectric ceramics were prepared by stereolithography technique. The influence of different sintering holding time (4h∼8h) on the micromorphology, relative density, shrinkage, electric properties, and photoluminescence properties were systematically investigated. The KNNLN-Er ceramics show the coexistence of orthorhombic and tetragonal structures. The grain size increases obviously and then decreases slightly with the holding time increasing. The KNNLN-Er ceramics exhibit good piezoelectric performance (piezoelectric constant d 33 ∼97 pC/N, electromechanical couple coefficient k t ∼0.36) and the moderate transparency of 34% when the holding time is 6h during sintering at 1120°C. Besides, the intensity of the photoluminescence emission spectra increases with the holding time increasing. Furthermore, in order to estimate the properties of the KNNLN-Er transparent ceramics, an ultrasonic transducer with a center frequency of 10.5 MHz was fabricated, which can be used for photoacoustic and fluorescence imaging. The results indicate that the KNNLN-Er ceramics have potential for multimode imaging applications. [ABSTRACT FROM AUTHOR]

Tungsten trioxide (WO 3) is a classical electrochromic (EC) material with advantages of abundant reserves, high coloration efficiency and cyclic stability. However, WO 3 films are often accompanied by a narrow spectrum of modulation due to a single-color change from transparent to blue. In this work, we report a wide-spectrum tunable WO 3 ·H 2 O nanosheets EC film solvothermally grown on fluorine-doped tin oxide (FTO) glass. Interestingly, the crystalline WO 3 ·H 2 O nanosheets film is transformed into amorphous WO 3 after annealing at 250 °C for 1 h. The amorphous film can be transformed into crystalline WO 3 film by increasing the annealing temperature to 450 °C. After annealing at 250 °C, the WO 3 film exhibits an optical modulation of 75.8% in a broad solar spectrum range of 380–1400 nm and blocks 88.9% of solar irradiance. Fast switching responses of 4.9 s for coloration and 6.0 s for bleaching, and a coloration efficiency of 86.4 cm2 C−1 are also achieved. Additionally, the WO 3 film annealed at 250 °C also demonstrates an excellent cyclic stability, where 99.6% of the initial optical modulation can be retained after 1500 cycles. This simple and mild solvothermal method used in this work provides a new idea for the preparation of wide-spectrum tunable WO 3 EC films. [ABSTRACT FROM AUTHOR]

Herein, high-performance 0.11 Pb(In 1/2 Nb 1/2)O 3 -0.89 Pb(Hf 0.47 Ti 0.53)O 3 -0.8Ta 2 O 5 (PIN-PHT-0.8Ta) ceramics are successfully synthesized. In addition, performance improvement is comprehensively analyzed from viewpoints of microstructure, phase structure and electrical properties. Experimental results reveal that the addition of Ta 2 O 5 changes phase structure of PIN-PHT ceramics from ferroelectric tetragonal phase to rhombohedral phase. This leads to the appearance of morphotropic phase boundaries (MPBs). At the same time, the addition of Ta 2 O 5 reduces grain size and enhances grain uniformity. Also, Ta 2 O 5 doping improves internal and external contribution of piezoelectric response, which greatly improves dielectric, piezoelectric and ferroelectric properties of PIN-PHT. Key performance parameters include d 33 , k p , T C , ε r and tan δ , which are found to be 630 pC/N, 0.73, 322.6 °C, 1917 and 1.55%, respectively. In particular, thermal stability of PIN-PHT-0.8Ta ceramics is found to be higher than PZT-based ceramics, as well as d 33 value and performance retention rate of PIN-PHT-0.8Ta are found to be 560 pC/N and 89% at 300 °C, respectively, which are far superior to commercial PZT-5 and PZT-8 ceramics. These properties indicate potential of PIN-PHT-0.8Ta ceramics in high-temperature applications. [ABSTRACT FROM AUTHOR]

In this work, CuF 2 -doped 0.08 Pb(In 0.5 Nb 0.5)O 3 –0.92 Pb(Hf 0.47 Ti 0.53)O 3 (PIN–PHT + CuF 2) ceramics were prepared via traditional solid-state route using lower temperature than conventional environment. Resultant materials were found to have high Curie temperature, high mechanical quality factor and excellent piezoelectric performance. The phase composition as well as piezoelectric, dielectric and ferroelectric properties of the samples were detailedly studied, and Rayleigh's law fitting method was used to explore the piezoelectric response mechanism. Results indicate that the addition of CuF 2 makes PIN–PHT lattice shrink, the phase composition of morphotropic phase boundary (MPB) is more symmetrical, that is, the content difference between rhombohedral and tetragonal phases decreases, and both intrinsic and extrinsic contributions of piezoelectric response are improved. For CuF 2 doping content of 0.75-at%, samples sintering at 1100 °C exhibited excellent overall performance, its dielectric and piezoelectric properties at room temperature and Curie temperature reach excellent values, i.e., d 33 = 488 pC/N, T C = 348 °C, ε r = 1630, tan(δ) = 0.14%, Q m = 387, and k p = 0.6. More importantly, after depolarization at 200 °C, d 33 still remained at 460 pC/N. The combined results show CuF 2 -doped PIN–PHT ceramics can be prepared at lower temperatures as well as have lower losses and higher values of Q m. These findings indicate that PIN–PHT + CuF 2 ceramics have greater ease of production and significantly improved application prospects, particularly as a result of their high temperature stability. [ABSTRACT FROM AUTHOR]

This paper reports a nanomixed valence FeWO 4 -coated 2D Ti 3 C 2 MXene (FW-MX) photocatalyst synthesised by a simple hydrothermal method. Ciprofloxacin, the main target pollutant, exhibited superior adsorption performance and high catalytic activity in the light-assisted Fenton system. In just 1 h, the removal rate of ciprofloxacin reached an impressive 76.89% using a minimal amount of FW-MX (10 mg). Meanwhile, the material exhibited good stability. Furthermore, the successful formation of mixed-valent FeWO 4 accelerated the rate-limiting step of Fe(III)/Fe(II) conversion, thereby enhancing the reactivity of the in situ photo-Fenton system. In the light-assisted Fenton system, FW-MX demonstrated greater potential compared to other common antibiotics, as FW-M100 exhibited superior photoreduction performance for heavy metal ions under the photo-Fenton oxidation system. This could further advance the practical application of AOPs technology in industrial wastewater treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

This work reports on optimizing the Indirect Indentation Method for measuring the elastic properties of brittle materials by indentation. The method employs a thin metallic film that protects the brittle material by absorbing the inelastic damage causes by the penetrating indenter. It applies hyperbolic identities to the Zhou-Prorok Model for thin film indentation that approach an asymptote as the indenter advances toward the film/substrate interface. The slope of this asymptote has been shown to be directly related to the elastic modulus of the brittle material being tested. A parameter study was conducted and revealed that the method can be optimized when the film Poisson's ratio is lower than the brittle material tested. This more directly transfers the indenter load to the substrate, enabling it to participate in the composite elastic response earlier in the indentation process. The result is an expanded range of fit of the experimental data to the models linear asymptote, providing more accurate elastic property measurements. Chromium was identified as an ideal film material due to its low Poisson's ratio, ductility and ability to be deposited onto most ceramics with a strong interface. The improvement was demonstrated on 5 brittle materials with a wide variety of elastic properties; SiC, Al 2 O 3 , MgO, SiO 2 , CaCO 3. [ABSTRACT FROM AUTHOR]

VO 2 (D) precursor with multi-step petaloid lamination structure was prepared by hydrothermal method, and then VO 2 (M) sample maintaining similar morphology and geometry with that of as prepared VO 2 (D) was obtained by subsequent annealing. The XRD Pattern of VO 2 (D) precursor and annealed samples at different temperature confirms the formation of required crystalline phases and exposes the presence of other intermediate phases. Surface morphology has been analyzed by SEM characterization, which reveals the variation in petaloid microstructure of the annealed samples at different temperatures. The reflection loss measurement results show that multi-step petaloid laminated structure VO 2 (M) sample has excellent microwave absorption performance. The sample annealed at 570 °C has the minimum reflection loss value of −37.99 dB at 3.5 mm, and the effective absorption bandwidth (RL < −10 dB) is up to 4.01 GHz at 1.3 mm. Detailed study shows that the excellent microwave absorption performance of the sample results from the combination of its geometry shape/surface polarization, induced loss and resistance loss. In addition, the curvature of the boundary of the laminated structure also affect the microwave absorption performance of the absorber. The discovery of this work effectively broadens the application of VO 2 (M) and provides a new idea for the design of new absorbing materials with tailored particle morphology. [ABSTRACT FROM AUTHOR]

A series of novel metal W connected Z-scheme C fibers@WO 3-x (0 ≤ x < 3) core-shell composites were developed by simply pyrolyzing preoxidized polyacrylonitrile fibers impregnated with slurries of WO 3 nanopowder in absolute ethanol in a vacuum furnace. Such structured composites are a kind of more excellent solar-driven photocatalyst for degrading various aqueous organic and inorganic environmental pollutants, compared with pure tungsten oxides catalysts under the same condition. The optimally selected composite catalyst (x = 2.01) was also applied in photocatalytically purifying waste water from paper mills under sunlight, presenting high efficiency in reducing chemical oxygen demand, biology oxygen demand and heavy metal Cr content, displaying great prospect in environmental remediation through removing various toxic industrial chemicals. The greatly enhanced photocatalytic performance could be mainly ascribed to the C fiber core and metal W connection layer between the tungsten oxides and C core in the composites, which can promptly conduct electrons and promote the separation of photogenerated electrons and holes. Moreover, this work provides a simple, eco-friendly and very efficient synthesis approach, which will be of much help to design diversified semiconductors composite structures, and suitable for large-scale production and thus practical industrial application. [ABSTRACT FROM AUTHOR]

Abstract The PZT ceramics with different weight content from 78% to 89% were printed using the stereolithography method. The piezoelectric properties as well as the microstructure of the ceramics were investigated in detail. X-ray patterns and Raman spectra demonstrate that the steady PZT tetragonal phase has already formed in these sintered ceramics. Besides, the piezoelectric constant and dielectric constant were 212–345 pC/N and 760–1390, which were sligthly lower than that of the dry pressing disk. Furthermore, a two-dimensional ultrasound transducer array (8 × 8) was designed and developed to evaluate the properties of the 3D-printed PZT ceramics. [ABSTRACT FROM AUTHOR]

Abstract: The microstructure and electric properties of the rhombohedral–tetragonal morphotropic phase boundary (MPB) composition 0.8Bi1/2Na1/2TiO3–0.2Bi1/2K1/2TiO3 have been investigated. X-ray and electron diffraction results substantiate the co-existence of tetragonal and rhombohedral phases. The ferroelectric domains were clearly observed by electron microscopy. The oxygen octahedron tilting of the samples was studied by SAED. Both saturated polarization–electric field and butterfly shaped strain–electric field hysteresis loops prove that the MPB composition shows typical ferroelectric nature. The detailed microstructure–property characterization may shed light on the physical property of further work on BNT–BKT around morphotropic phase boundary. [Copyright &y& Elsevier]

Abstract: Two series of raw materials were adopted to form TiAl/Ti2AlC composites: Ti/Al/TiC and Ti/Al/C. Differential thermal analysis (DTA) of starting powers and X-ray diffraction (XRD) of samples sintered at different temperatures from 600°C to 1300°C by hot pressing were utilized to analyze the phase transformation and the mechanism of synthesis. Scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy (EDS) was utilized to investigate the morphology characteristics of the products. The experimental results showed that Ti reacted with Al to form TiAl intermetallics below 900°C; and above 900°C, TiAl reacted with TiC to produce dense TiAl/Ti2AlC composites. The products sintered at 1200°C had fine crystals and dense fibres, and the distribution of Ti2AlC particles in TiAl matrix was homogeneous. [Copyright &y& Elsevier]

The Li + conductivity of Li 7 La 3 Zr 2 O 12 (LLZO) solid electrolytes was optimized by controlling the addition of the dopant (Al) into the crystal structure. A solution-based synthesis method was used to minimize Al segregation and ensure a homogeneous substitution into the garnet framework. Neutron and x-ray diffraction were used to monitor the structural transition from tetragonal to cubic LLZO. It was found that the critical dopant concentration (x c) required to stabilize the cubic phase was 0.18 mol pfu. The maximum ionic conductivity of 5.54 × 10−4 S/cm was obtained at the critical composition. The enhanced conductivity was achieved by accurately controlling the vacancy density at the active Li octahedral sites. Neutron structure refinements were used to validate the changes in Li vacancy distribution at different dopant concentrations. Impedance measurements reveal a strong dependence of Li+ transport properties on Al concentration, specifically around the critical dopant concentration x c = 0.18 mol pfu. These findings demonstrate the importance of fine-tuning composition and provide guidance for engineering improvements in ionic conductivity. [Display omitted] [ABSTRACT FROM AUTHOR]

In this report, the effects of the calcination temperature of (K 0.5 Na 0.5 )NbO 3 (KNN) powder on the sintering and piezoelectric properties of KNN ceramics have been investigated. KNN powders are synthesized via the solid-state approach. Scanning electron microscopy and X-ray diffraction characterizations indicate that the incomplete reaction at 700 °C and 750 °C calcination results in the compositional inhomogeneity of the K-rich and Na-rich phases while the orthorhombic single phase is obtained after calcination at 900 °C. During the sintering, the presence of the liquid K-rich phase due to the lower melting point has a significant impact on the densification, the abnormal grain growth and the deteriorated piezoelectric properties. From the standpoint of piezoelectric properties, the optimal calcination temperature obtained for KNN ceramics calcined at this temperature is determined to be 800 °C, with piezoelectric constant d 33 =128.3 pC/N, planar electromechanical coupling coefficient k p =32.2%, mechanical quality factor Q m =88, and dielectric loss tan δ =2.1%. [ABSTRACT FROM AUTHOR]

Niobium-doped titania (TNO) film can be used as a transparent conductive oxide (TCO) film due to its excellent conductivity and visible transparency. The performances of TNO sputtering targets are thus critical issues in optimizing sputtered films. This study clarifies the influences of inert and reducing atmospheres on the microstructure, densification, crystal structure, and electrical properties of TNO sputtering targets. The results indicate that a sintering atmosphere of 90% Ar–10% H 2 can result in a lower sintered density, larger grain size, and lower resistivity than can an atmosphere of Ar, followed by one of air. Sintering in 90% Ar–10% H 2 or Ar obviously decreases the resistivity of TiO 2 , from >10 8 Ω cm to <10 −1 Ω cm, and the TNO target, from >10 1 Ω cm to <10 −1 Ω cm. The resistivity of TNO target sintered at 1200 °C in 90% Ar–10% H 2 is as low as 1.8×10 −2 Ω cm. [ABSTRACT FROM AUTHOR]

The influence of micro-sized Cr 2 O 3 particles on the corrosion, mechanical and thermal control performance of plasma electrolytic oxidation coated Mg was studied. More contents of Cr 2 O 3 particles were embedded into phosphate containing PEO coatings compared with coatings produced from silicate based electrolytes, resulting in green coatings with enhanced thermal control and mechanical property. The existence of particles has slightly improved the corrosion resistance and hardness of the coating. It was found that the absorptance of the coating was increased if higher concentration of Cr 2 O 3 particles is incorporated into the layer, which is probably ascribed to low band gap of Cr 2 O 3. [ABSTRACT FROM AUTHOR]

High-entropy perovskite cathode materials with the coupling of five or more different component transition metal species can provide great flexibility in modulating the electronic properties and catalytic activities for solid oxide fuel cells (SOFCs). Herein, as-prepared Sr-free high-entropy perovskite oxide LaMnO 3-δ (LMO) is homogeneously incorporated five transition metal species Mn, Fe, Co, Ni and Cu (LaMn 0.2 Fe 0.2 Co 0.2 Ni 0.2 Cu 0.2 O 3-δ , HE-LMO) in B-site of perovskite, presenting enhanced electrochemical performance. The cell performance of anode supported SOFCs with HE-LMO cathode is almost one point five times (550.89 mW cm−2 at 800 °C) of those with LMO cathode. Accordingly, the electrode polarization resistances of HE-LMO cathode are reduced from 0.532 Ω cm2 to 0.212 Ω cm2 at 800 °C and from 4.051 Ω cm2 to 1.538 Ωcm2 at 650 °C, respectively. All the results demonstrate that it would be a feasible way to design high-performance cathode materials with multi-component transition metal coupling at reduced temperature. [ABSTRACT FROM AUTHOR]

Oxygen vacancies-rich iron-based perovskite-like oxides La x Sr 3-x Fe 2 O 7- δ (x = 0, 0.25, 0.5) have been studied towards application as both anode and cathode materials for symmetrical solid oxide fuel cells (SSOFCs) at intermediate temperatures utilizing their excellent thermo-chemical structural stability. The conduction mechanism of La x Sr 3-x Fe 2 O 7- δ was investigated according to the effect of La content on electrical conductivity and oxygen nonstoichiometry. Consequently, La x Sr 3-x Fe 2 O 7- δ was used simultaneously as reversible symmetrical electrodes for YSZ electrolyte supported SSOFCs with GDC buffer layers. The maximum power density of La x Sr 3-x Fe 2 O 7- δ - GDC symmetrical electrodes increased from 350 mW cm−2 to 480 mW cm−2 at 800 °C, and the corresponding cell polarization resistance decreased from 0.18 Ω cm2 to 0.16 Ω cm2, respectively. The enhanced performance is attributed to the improved electrical conductivity and electro-catalytic activity by the partial substitution of Sr with La. These results demonstrate that new iron-based perovskite-like oxides are promising for applications in intermediate temperatures SSOFCs. [ABSTRACT FROM AUTHOR]

A series of direct Z-scheme FeIn 2 S 4 /Bi 2 WO 6 hierarchical heterostructures with intimate interface contacts were synthesized by in-situ growth route and characterized by systematical analyses. All as-prepared FeIn 2 S 4 /Bi 2 WO 6 nanocomposites showed significantly enhanced photocatalytic activity towards photodegradation for the removal of tetracycline hydrochloride (TCH) in comparison with individual FeIn 2 S 4 and Bi 2 WO 6. Meanwhile, the highest photocatalytic degradation activity can be achieved by modulating adding amount of FeIn 2 S 4 in FeIn 2 S 4 /Bi 2 WO 6 nanocomposites and the optimized component ratio of FeIn 2 S 4 to Bi 2 WO 6 is determined to be 10 wt%. The enhanced photocatalytic activity could be ascribed to efficient separation between photogenerated holes and electrons based on the construction of direct Z-scheme system. The high photocatalytic stability of resultant 10 wt% FeIn 2 S 4 /Bi 2 WO 6 nanocomposites was revealed through six successive recycling reactions. The main intermediate generated during TCH photodegradation was explored by HPLC-MS. Besides, the direct Z-scheme photocatalytic mechanism was confirmed by band position analysis, electron spin resonance (ESR) and active species capture experiment. [ABSTRACT FROM AUTHOR]

As important functional materials for absorbing and attenuating incident electromagnetic waves, microwave absorption (MA) materials have found a wide range of applications in civil and military fields. In addition to the study of the compositions, the structural design of the MA materials is also a research hotspot in the field. Among the various structures, the one-dimensional (1D) structure has drawn wide attention because of the unique shape anisotropy and spatial confinement effect. Electrospinning technology has become one of the main ways to prepare continuous 1D micro-nano fibers due to the advantages of many types of spinnable materials, low spinning cost, and high controllability of process parameters. This review involves an introduction and a classification of the research progresses achieved in electrospinning technology concerning MA nanofibers from the perspective of compositions, as well as the list of their minimum reflection loss (RL min) and effective absorption bandwidth (EAB). [ABSTRACT FROM AUTHOR]

Three powders of Ba 0.95 Zr 0.1 Ce 0.7 Y 0.2 O 3-δ (BZCY095), BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ (BZCY), Ba 1.05 Zr 0.1 Ce 0.7 Y 0.2 O 3-δ (BZCY105) with different Ba contents were synthesized using solid state reaction method. The effects of Ba non-stoichiometry on structure defect, sinterability and hydrogen permeability were investigated in details. The results of XRD and SEM revealed that the excess of BaO (BZCY105) was beneficial to the formation of single phase and membrane sinterability, while the deficiency of BaO (BZCY095) was counterproductive because of the vaporization of BaO at high temperature. Moreover, according to XPS, EPR, FT-IR, Raman and UV–Vis analysis, BZCY105 contained more oxygen vacancies than BZCY095 and BZCY. Additionally, the hydrogen permeation flux through BZCY105 membrane was the highest one because excess BaO favors protonic and grain boundary conductivities. Finally, the mechanism of Ba non-stoichiometry in Ba 1-x Zr 0.1 Ce 0.7 Y 0.2 O 3-δ was proposed. For BZCY105, the excess BaO might be substituted into Ce site to form more oxygen vacancies. As for BZCY095, the dopant of Y might tend to be substituted into Ba site, decreasing the concentration of oxygen vacancy. [ABSTRACT FROM AUTHOR]

Novel ZnO/ZnFe 2 O 4 /Ag hollow one-dimensional multicomponent heterojunctions with different ZnO/ZnFe 2 O 4 ratios were successfully obtained via a simple electrospinning method. These multicomponent heterojunctions exhibited a largely enhanced photocatalytic performance for various reactions compared with pure ZnFe 2 O 4 without heterojunctions, ZnO/ZnFe 2 O 4 and ZnFe 2 O 4 /Ag with single heterojunctions. The enhancement can be mainly ascribed to the synergism of multicomponent heterojunctions, which can significantly improve the optical absorption abilities, prompt the separation of photogenerated carriers, and depress the recombination of electron-hole pairs. Hence, the simultaneous and efficient generation of electrons and holes with strong reduction and oxidation abilities, respectively, can lead to effective reaction with the target degradants. In addition, the unique hollow nanofiber structure can also prompt the activities by decreasing the distance for charge carrier transfer to the solution during the photocatalytic process. Additionally, the influence of the number of heterojunctions on the photoactivity was also discussed via varying the ZnO loading amount. This work displays an ingenious design to elevate photocatalytic performances of spinel ZnFe 2 O 4 for solving its biggest problems in the photocatalytic applications, and reveals the rational design of photocatalysts for efficient water pollutants removal. [ABSTRACT FROM AUTHOR]

Calcium phosphate cement (CPC) scaffolds have been widely used as bone graft substitutes, but their clinical application is restricted by the undesirable osteoinductivity and slow degradability. We developed new CPC microspheres loaded with bone morphogenetic protein-2 (BMP-2)-derived peptide P24 (P24/CPC). The BMP2-derived peptide P24 was evenly pasted with CPC microspheres, which maintained the bioactivity of BMP-2. We evaluated the effect of the P24/CPC microspheres on osteogenesis and examined the underlying mechanism in vitro and in vivo. The in vitro studies showed that the bioactivity of P24 was preserved in the P24/CPC microspheres and the P24 release duration lasted up to 39 days. The P24/CPC microspheres with different proportions of P24 (2% and 4%) induced high proliferation of bone marrow stromal cells (BMSCs) and well supported cell adhesion on the sphere surfaces. Furthermore, the cells exhibited higher alkaline phosphatase activity and higher expression of osteogenic-specific genes ( OCN and Runx2 ) in 4% P24/CPC than in the CPC and control groups ( P <0.05). Therefore, these findings indicated the enhanced osteoblastic differentiation of BMSCs on P24/CPC microspheres. In vivo osteoinductive studies revealed that the degrees of ectopic osteogenesis in the dorsal muscle pocket of rat were significantly higher in the P24/CPC microspheres than in the CPC microspheres. Finally, the CPC or P24/CPC microspheres were implanted into rabbit femoral condyle defects and P24/CPC serial groups were observed for 4, 8, and 12 weeks. Computed tomography (CT) and histological and histomorphological studies proved that P24/CPC microspheres were biocompatible, bioabsorbable, and osteoinductive. In conclusion, this study demonstrated that P24/CPC microspheres can enhance osteogenesis in vitro and promote bone regeneration in vivo. Furthermore, our results confirmed that BMP2-derived peptide P24 can have a beneficial effect on the bone-generating properties of CPC microspheres, suggesting that P24/CPC microspheres are strong potential bone graft substitutes in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Abstract: Sr2Fe1−0.5x Mo1−0.5x Ir x O6 ceramics (x=0, 0.02, 0.04, 0.06, and 0.08) have been synthesized and the structures, magnetic and transport properties have been investigated. X-ray diffraction reveals a very low solution limit of x=0.06, which however, results in significantly decreased Fe/Mo ordering degree and thus decreased magnetization value. On the other hand, the Curie temperature (T c) rises from 390K (x=0) to 400K (x=0.02) firstly, and then decreases to 360K and 340K for the compositions with x=0.04 and 0.06, respectively. In addition, the resistivity and magnetoresistance drop drastically with increasing x. The composition with x=0 shows semiconductor transport behavior in the temperature range of 10–400K, whereas the other compositions show a minimum resistivity around 120K. These results are discussed in detail by considering the effects of Ir substitution. [Copyright &y& Elsevier]