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Oxygen minimum zones (OMZs) in the ocean are areas with dissolved oxygen (DO) concentrations below critical thresholds that impact marine ecosystems and biogeochemical cycling. In the northern Indian Ocean (NIO), OMZs exhibit a tendency to expand in mesopelagic waters and contribute significantly to global nitrogen loss and climate change. However, the microbial drivers of OMZ expansion in the NIO remain understudied. Here, we characterized bacterial communities across DO gradients in the NIO using high-throughput 16S rRNA gene sequencing. We found that Marinimicrobia, Chloroflexi, and the SAR324 clade were enriched in both oxygen-deficient and low oxygen mesopelagic waters. Furthermore, Marinimicrobia, Chloroflexi, and the SAR324 clade exhibited a significant negative correlation with DO (P < 0.01), suggesting that they were well-adapted to the oxygen-deficient OMZ habitat. Functional predictions revealed heightened nitrogen metabolism in OMZs, particularly nitrate reduction, suggesting its pivotal role in nitrogen loss. These findings underscore the importance of microbial communities in driving OMZ expansion in the NIO and highlight their implications in global biogeochemical cycles and climate change. [ABSTRACT FROM AUTHOR]

In this work, SnO2 hollow microspheres functionalized with different incorporated amounts of Pt@Co3O4 complex catalyst were innovatively designed by using an MOF template. The results show that sensor based on the optimal incorporated amount of Pt@Co3O4 not only greatly enhances the response value of SnO2 to formaldehyde (Rair/Rformaldehyde = 4240 toward 100 ppm) but also decreases the low detection limit (50 ppb), which is quite outstanding compared with other SnO2-based formaldehyde sensors. Further analysis proves that the content of oxygen vacancy and chemisorbed oxygen and the catalytic effect of ultra-small Pt play the key roles in improving the formaldehyde sensing performance. Meanwhile, this present work demonstrates that oxide semiconductors functionalized with the derivatives of MOF templated catalysts may lead to the discovery of new material systems with outstanding sensing performance. [ABSTRACT FROM AUTHOR]

Heat release characteristic of coal oxidation is one of the key factors influencing spontaneous combustion. To investigate the heat release characteristics of coal low-temperature oxidation under oxygen deficient atmosphere, by C80 calvet calorimeter, the heat flow of coal oxidation below 250 ℃ was tested under various atmospheres with 5%, 9%, 13%, 17%, and 21% oxygen concentrations. The initial temperature of heat release and quantity of heat release were analyzed. Furthermore, the apparent activation energy of coal oxidation was calculated. The results show that the initial temperature of heat release of coal fluctuates and increases with the decrease of oxygen concentration, while the intensity and quantity of heat release and apparent activation energy decrease. Moreover, there is a critical oxygen concentration, below which the heat release behaviors during coal oxidation will be inhibited obviously. There are two critical oxygen concentrations foreach of the tested coal samples, namely, 13% and 9%.

Hafnium oxide acts as a functional dielectric in a variety of traditional and emerging nonvolatile memory technologies. To investigate the effect of heavy ion irradiation on its crystalline structure, highly textured hafnium oxide films were irradiated with 1.635 GeV Au ions of fluences ranging from $1\times 10^{9}$ to $7\times 10^{12}$ ions/cm2. For monoclinic hafnium oxide films, a fluence-dependent defect-induced phase transition to a defect-stabilized tetragonal phase is identified. In low-temperature tetragonal hafnium oxide films, the X-ray diffraction (XRD) patterns show an out-of-plane lattice constant decrease with increasing irradiation fluence. Observed crystalline changes are strikingly similar to trends found for oxygen-engineered hafnium oxide films, directly grown at varying oxidation conditions. The correlation of structural changes with in vacuo electron spectroscopy data of oxygen-engineered films suggests that the irradiation of hafnium oxide leads to an oxygen loss that increases with fluence. Therefore, the underlying mechanism of the monoclinic to tetragonal phase transition is obviously directly related to oxygen defects. This new information allows predictions of device stability under swift heavy ion irradiation of hafnium oxide-based devices. [ABSTRACT FROM AUTHOR]

In this work, SnO2 hollow microspheres functionalized with different incorporated amounts of Pt@Co3O4 complex catalyst were innovatively designed by using an MOF template. The results show that sensor based on the optimal incorporated amount of Pt@Co3O4 not only greatly enhances the response value of SnO2 to formaldehyde (Rair/Rformaldehyde = 4240 toward 100 ppm) but also decreases the low detection limit (50 ppb), which is quite outstanding compared with other SnO2-based formaldehyde sensors. Further analysis proves that the content of oxygen vacancy and chemisorbed oxygen and the catalytic effect of ultra-small Pt play the key roles in improving the formaldehyde sensing performance. Meanwhile, this present work demonstrates that oxide semiconductors functionalized with the derivatives of MOF templated catalysts may lead to the discovery of new material systems with outstanding sensing performance.

TiO2 thin films were deposited on quartz substrate by RF-magnetron sputtering technique. The effect of varying oxygen fraction f ( O 2) = ( O 2 / (Ar + O 2) on the surface morphology, structure, electrical and optical properties was investigated. Decreasing the oxygen fraction promotes phase transformation to the extent of isolating anatase phase with well oriented A(101) preferred crystal orientation at f ( O 2) of 0.1%. The refractive index dispersion curves were utilized to estimate the single oscillator parameters. In addition, an enhancement in the electrical conductivity to 2. 6 × 1 0 − 2 Ω − 1 cm − 1 at f ( O 2) = 0. 1 % was established. This enhancement was attributed to the deficiency of oxygen as well as the formation of anatase phase. [ABSTRACT FROM AUTHOR]

Oxygen-deficient metal oxides have seen increased application in the field of free radical biology, whereby their electronic structure imparts unique antioxidant properties. In this work, we use the facile, one-step, cost-effective method of spray pyrolysis to synthesize oxygen-deficient lanthanum oxide (La2O3-x), nanoparticles. Structural and morphological characterization revealed the formation of an aggregate of La2O3-x nanocrystals in the form of hollow spheres. Photocatalytic activity (PCA) was benchmarked against commercial La2O3 and Evonik Aeroxide® TiO2 P25 via dye degradation experiments and a significant pH dependence of PCA is reported. Furthermore, chemical assays based on the Fenton reaction verified the scavenging properties of the synthesized materials towards reactive oxygen species (ROS), with increased scavenging of hydroxyl (∙OH) and superoxide (O2∙–) radicals observed at pH 4.8. Biological assays (in vitro), with a 24 h incubation period in the presence of the La2O3-x nanoparticles, were conducted upon a non-malignant human keratinocyte cell line (HaCaT). The La2O3-x nanoparticles showed no toxicity when compared with the control over a significant concentration range. Biocompatibility with the non-malignant HaCaT cell line suggests the future application of La2O3-x as a doping material for inorganic oxides used as UV filters or as an antioxidant to mitigate oxidative stress by scavenging free radicals in conditions such as melanoma and inflammation. [ABSTRACT FROM AUTHOR]

The demand of materials for energy conversion and storage is increasing to address the issues related to the depletion of fossil fuels. In the present study, oxygen deficient vanadium oxide (V 2 O 3) has been synthesized in an autoclave at 500 °C for 4 h. The reaction temperature, time and atmosphere affect the pure phase formation of V 2 O 3. The structural, morphological and surface characteristics of pure phase V 2 O 3 has been analysed by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS), respectively. The phase transition with respect to temperature has been confirmed by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). The electrocatalytic hydrogen evolution reaction (HER) activity has been studied in an acidic medium. The synthesized sample shows higher cyclic stability for 1000 cyclic voltammetry (CV) cycles. It also exhibits a lower Tafel slope of 81.2 mVdec−1. The electrochemical double layer capacitance (EDLC) measurements was done via CV measurements performed at various scan rates. The observed EDLC value of synthesized sample is 242.6 μFcm−2. The study predicts potential applications of V 2 O 3 nano structures for electrochemical applications like HER and supercapacitors. • Controlled synthesis of intermediate pure V 2 O 3 nano structures. • Effect of temperature and time affect the phase transformation in an autoclave. • Efficient and stable elctrocatalyst for HER. • Oxygen deficiency in V 2 O 3 enhance the stability for capacitor applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Blackened ferroelectric semiconductor extends visible light absorption. • In-situ introduction of oxygen-deficient by Al-reduction. • BaTiO 3 /BaTiO 3− x / g -C 3 N 4 heterojunctions improve the catalytic effect of the photocatalysts. In-situ introduction of oxygen-deficiency in traditional semiconductor nano-oxides has been proved to be one of the most effective strategies for enhancing light-harvesting and energy conversion efficiency. This work intends to correlate oxygen vacancy of ferroelectric oxygen carriers with redox properties. The crystalline-BaTiO 3 / amorphous-BaTiO 3− x / crystalline- g -C 3 N 4 composite nanoparticles have been synthesized by combining the hydrothermal synthesis and aluminothermic reduction method. The aluminothermic reduction established a shell of amorphous layer contributed by the oxygen vacancy generation, which extended range of sunlight absorption. Meanwhile abundant oxygen vacancies simulate the generation of reactive oxidizing species, resulting in intensive photodegradation ability. The effective degradation process is the result of synergistic interaction among heterojunction, reactive radical species and abundant oxygen vacancies, the degradation efficiency of methylene blue (MB) solution reach to 99.47% within 30 min, which demonstrates the promising prospects of BaTiO 3 /BaTiO 3 − x / g -C 3 N 4 as costing effective, highly stable and efficient photocatalysts. [ABSTRACT FROM AUTHOR]

Oxygen deficient doped niobate, Nd 0.7 Sr 0.3 NbO 2.7 , has been prepared by the conventional solide solide route. Then, dielectric data has been carried out by means of impedance spectroscopy in a wide frequency and temperature ranges. Dielectric properties are analyzed using different dielectric formalisms such as complex permittivity ε*, dielectric loss tangent tan ( δ ) and complex electric modulus M*. These formalisms obey to the Arrhenius law with low values of the activation energy. The highest dielectric constant has been observed at room temperature up to 0.5 MHz which can be suitable for various potential applications. The colossal dielectric constant is related to electrons hopping. The dielectric loss tangent spectra prove the contribution at least of two mechanisms. The scaling behavior of both dielectric loss tangent and imaginary component of electric modulus suggests the relaxation mechanism is temperature independent. The complex electric modulus plot only emphasizes the grain capacitance as smallest capacitance. [ABSTRACT FROM AUTHOR]

Defect engineering and the high index surface (HIF) can be regarded as two effective methods to tuning the microstructure of catalysts and photocatalytic activities. So far, the integration of the synergistic effects of oxygen vacancies and HIF advantages into semiconductors to enhance photocatalytic performance has received little attention. Herein, Black In 2 O 3−x/ In 2 O 3 with oxygen vacancy and exposed (321) surface active crystal plane has been synthesized as excellent photocatalysts via a facile method. The catalysts of Black In 2 O 3−x /In 2 O 3 can reach the highest photocatalytic hydrogen evolution rate (1046 μmol h−1 g−1) and degradation efficiency of MB (0.017 min−1) with 120 min, respectively. As a special phase junction, Black In 2 O 3−x /In 2 O 3 could effectively boost the separation and transfer of photogenerated charges because of unique defect homojunction microstructure resulting in exposing abundant photocatalyst redox active sites. The experiment characterization and density functional theory (DFT) calculations can further employ to unveil mechanism of enhanced hydrogen evolution reaction (HER) activity. It is obvious that enhanced HER activity was attributed to synergy of oxygen defect and exposed (321) surface active crystal planes due to electron distribution and lower Gibbs free energy of H adsorption. This work might open up new avenues to integrate exposed facets and oxygen vacancy for enhancing the photocatalytic hydrogen evolution with renewable energy sources and environmental remediation. [Display omitted] • Black In 2 O 3−x/ In 2 O 3 with oxygen vacancies and exposed (321) plane was successfully prepared. • Black In 2 O 3−x/ In 2 O 3 has amorphous domains of In 2 O 3−x and crystalline regions of In 2 O 3. • Black In 2 O 3−x/ In 2 O 3 can act as "nano-heat-sources" to enhance photocatalytic reaction. • Black In 2 O 3−x/ In 2 O 3 with exposed (321) planes show much lower adsorption energy of H 2 O (Δ G H2O*). • Enhanced HER activity was attributed to synergy of oxygen defects and exposed (321) planes. [ABSTRACT FROM AUTHOR]

Mesoporous La 0.7 Sr 0.3 MnO 3 (LSMO) films were prepared to determine the potential for applications within thermoelectric materials. The mesoporous structure induces a decrease in thermal conductivity due to increased phonon scattering, and an increase in the Seebeck coefficient due to an increased specific surface area. An increase in surface area induces an increase in oxygen vacancies which results in band narrowing and a filled Mn 3d state with the electron-combined oxygen. As a result, the mesoporous LSMO film showed an increased Seebeck coefficient and a reduced thermal conductivity but, in addition, showed a greatly increased electrical resistivity with the filled Mn 3d states. This abnormally large increase in electrical resistivity resulted in a reduced figure of merit for the LSMO film even after the introduction of a mesoporous structure. An effect of the applied mesoporous structure on the thermoelectric properties was shown to be varied due to a change in the amount of oxygen defects in the LSMO with a perovskite structure. [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanotube (CNT) wired and oxygen-deficient MoO3−x /CNT structures are fabricated via a facile hydrothermal reaction followed by controlled reduction in Ar/H2. The MoO3−x /CNT, which consists of 63 mol% MoO3 and 37 mol% MoO2, exhibits a much improved Li-storage property compared with the original MoO3/CNT structure when evaluated as an anode in the 0.05–3.0 V region. It is able to retain a capacity of 421 mAh g−1 towards Li after 100 cycles at 200 mA g−1, and deliver 293 and 202 mAh g−1 at current densities of 2 and 4 A g−1, respectively. It is suggested that the formation and recovery of a metallic MoO2 phase over the conversion reaction may account for the enhanced performance. [Copyright &y& Elsevier]

Abstract: Vapor-deposited molybdenum oxide films are used as low resistance anode interfacial layers in applications such as organic light emitting diodes (OLEDs) and organic photovoltaics (OPVs). A versatile method for the vapor deposition of molybdenum oxide layers is presented, which offers the control of the oxygen stoichiometry of the deposited films and their doping with hydrogen. The possibility of tuning the electronic structure of the deposited molybdenum oxides is also investigated by controlling oxygen deficiency and hydrogenation (the incorporation of hydrogen within the molybdenum oxide's lattice). To take advantage of the altered electronic properties of the non-stoichiometric Mo oxides, we embedded them as anode interfacial layers in organic optoelectronic devices. Large improvement in the operational characteristics of both electroluminescent devices and bulk heterojunction solar cells was achieved and correlated with the oxygen deficiency and the hydrogen content of the Mo oxides. [Copyright &y& Elsevier]

Abstract: The local structures of the oxygen deficient perovskites Sr2FeMnO5, Sr2FeMnO5.5, and Sr2Fe1.5Cr0.5O5 have been analyzed using neutron pair distribution function data. The results show that locally all three structures are more complex than implied by their average cubic structures and that the distributions of oxygen vacancies are not completely random on a local level. For both Sr2FeMnO5+y compounds it is found that there is no short range ordering of the Fe and Mn cations. For Sr2Fe1.5Cr0.5O5 there is evidence to suggest that the Fe/Cr distribution is not completely random and is locally ordered such that there are fewer FeFe nearest neighbor pairs than in a random distribution. Reverse Monte Carlo modeling of the pair distribution function data has provided the FeO, MnO, and CrO bond length distributions and information on the coordination numbers of the Fe, Mn, and Cr cations. In Sr2FeMnO5 it is found that the Fe3+ cations are most often in 4-fold coordination but there is also a large amount of Fe3+ in 5-fold coordination and a small amount in 6-fold coordination. The Mn3+ is split between 5-fold and 6-fold coordination. The MnO bond length distributions indicate that the Mn3+O6 octahedra and Mn3+O5 square pyramids are locally Jahn–Teller distorted. In Sr2FeMnO5.5 the Fe3+ is almost entirely 5 coordinate while the Mn4+ is almost entirely 6 coordinate. The Cr3+ in Sr2Fe1.5Cr0.5O5 is almost entirely 6-fold coordinated, giving the Fe3+ an average coordination number of 4.67. In Sr2FeMnO5 and Sr2Fe1.5Cr0.5O5 the Fe3+ and Sr2+ cations undergo local displacements which are driven by the oxygen vacancies, while the Mn3+ and Cr3+ cations remain near their positions in the average structures. In Sr2FeMnO5.5 these cations are not significantly displaced. The local coordination geometries are used to explain previously observed but yet poorly understood magnetic properties of these materials. [Copyright &y& Elsevier]

An oxygen deficient Li4Ti5O12 was investigated for lithium ion batteries (LIBs) in this work. Compared with nitrogen doping and pristine Li4Ti5O12, the oxygen deficient Li4Ti5O12 exhibits significant improvement of electrochemical performance, it could deliver a specific capacity of 75 mAh/g even at a high charge/discharge rate of 10C and exhibit excellent cycling performance. The results revealed in this work show that oxygen deficient control can be a promising way to improve high rate performance of the LIBs electrode materials. [ABSTRACT FROM AUTHOR]

Abstract: The size-dependent physicochemical and optical properties of silica nanoparticles have been studied. Significant increase in the specific surface area (SSA), concentration of silanol groups (δ OH) and apparent density (D a) were observed as the particle size reduced from ∼130 to ∼7nm. The decrease in the silanol number (α OH) and Si–O–Si bond angle in smaller particle size suggest that the silica structure, especially the surface has been significantly altered at nanoscale. This finding is supported by the presence of defect sites such as E′ centers and oxygen deficient centers (OCD). The stability of E′ centers (UV–vis analysis) increase linearly with the increase in particle size. The increase in the intensity of blue and green bands (PL analysis) with the decrease in the particle size are attributed to the higher silanol concentration and increased in the number of self-trapped exciton (STE)/OCD, respectively. The green band was blue-shifted with the decrease in the particle size. Overall, the silica nanoparticles have shown distinctive properties relative to the bulk silica. [Copyright &y& Elsevier]

Abstract: Titanium dioxide is a wide band gap (3.2eV) semiconductor which is photo-active when irradiated with UV light. For wider scale use of TiO2 as a photocatalyst, its activity needs to be extended to the visible light region (constituting 45% of total incident solar energy). A diffusion flame aerosol reactor (FLAR) with an oxygen lean environment in the particle formation zone has been used to synthesize oxygen deficient titanium suboxide (TiO x with x <2) nanoparticles. Using a standard-based electron energy loss spectroscopy (EELS) technique, the non-stoichiometry (x in TiO x ) in the flame synthesized particles has been quantified with high accuracy (uncertainty less than 3%). Under an oxygen lean environment in the particle formation zone, the non-stoichiometry in the TiO x particles is a function of the flame temperature. The value of x in the flame synthesized TiO x nanoparticles is in the range of 1.88< x < 1.94. Diffuse reflectance spectra confirmed that the oxygen deficient TiO x particles absorbed visible light. Visible light activity of the TiO x particles is demonstrated by photocatalytic degradation of methyl orange solution under visible light illumination. [Copyright &y& Elsevier]

Abstract: A new layered perovskite Sr2Al0.78Mn1.22O5.2 has been synthesized by solid state reaction in a sealed evacuated silica tube. The crystal structure has been determined using electron diffraction, high-resolution electron microscopy, and high-angle annular dark field imaging and refined from X-ray powder diffraction data (space group P4/mmm, a=3.89023(5)Å, c=7.8034(1)Å, R I=0.023, R P=0.015). The structure is characterized by an alternation of MnO2 and (Al0.78Mn0.22)O1.2 layers. Oxygen atoms and vacancies, as well as the Al and Mn atoms in the (Al0.78Mn0.22)O1.2 layers are disordered. The local atomic arrangement in these layers is suggested to consist of short fragments of brownmillerite-type tetrahedral chains of corner-sharing AlO4 tetrahedra interrupted by MnO6 octahedra, at which the chain fragments rotate over 90°. This results in an averaged tetragonal symmetry. This is confirmed by the valence state of Mn measured by EELS. The relationship between the Sr2Al0.78Mn1.22O5.2 tetragonal perovskite and the parent Sr2Al1.07Mn0.93O5 brownmillerite is discussed. Magnetic susceptibility measurements indicate spin glass behavior of Sr2Al0.78Mn1.22O5.2. The lack of long-range magnetic ordering contrasts with Mn-containing brownmillerites and is likely caused by the frustration of interlayer interactions due to presence of the Mn atoms in the (Al0.78Mn0.22)O1.2 layers. [Copyright &y& Elsevier]

• A dual strategy for NiCo 2 O 4 with unique morphologies and oxygen defects is used for Li-S batteries. • The NiCo 2 O 4-x exhibits the synergy of adsorption and catalysis for LiPSs. • The cell with NiCo 2 O 4-x modified separator shows the excellent electrochemical stability. Recently, lithium-sulfur batteries (LSBs) have been considered as the most potential energy storage system, but the application of LSBs is still confronted with significant challenges. One among the significant challenges is the low kinetics. In this work, we design the urchin-like structure of NiCo 2 O 4 to expose more catalytic sites to accelerate the lithium polysulfides (LiPSs) conversion. And the oxygen deficient in NiCo 2 O 4 with spinel type structure (space group Fd3m) leads to the excellent chemical affinity of NiCo 2 O 4-x for LiPSs. Moreover, because of the optimal distribution of electron on (3 1 1) plane of NiCo 2 O 4-x , the Gibbs free energies of the evolution from S 8 to Li 2 S on (3 1 1) plane of NiCo 2 O 4-x is much lower than that of NiCo 2 O 4 , illustrating the NiCo 2 O 4-x with the higher catalytic activity. Therefore, the cell with the NiCo 2 O 4-x modified separator exhibits a superior rate performance (632 mAh g−1 at 2.5 C) and a long cycle life (404 mAh g−1 at 1 C after 800 cycles) with excellent Li+ ion diffusion coefficient. The rational structural optimization makes NiCo 2 O 4-x become the efficient catalyst of LSBs. And the results promote the development of bimetallic oxides as catalyst in LSBs. [ABSTRACT FROM AUTHOR]

The oxygen-deficient hexagonal BaTiO3 shows huge dielectric constant. Because of the oxygen-deficient induced to change the valance from Ti4+ to Ti3+ and formed the charge imbalance in a lattice. However, this dielectric constant is easily disappeared when the oxygen-deficient is compensated. And it is difficult to control the amount of oxygen-deficient in hexagonal BaTiO3. In this study, the oxygen deficient is substituted by La to keep the charge imbalance. It was successful to retain the huge dielectric constant of La doped hexagonal BaTiO3. La3+ could induce to change the valance from Ti4+ to Ti3+. And it shows almost the same behavior on the complex plane of Z by an impedance measurement. La doped hexagonal BaTiO3 has a semiconductive behavior. [ABSTRACT FROM AUTHOR]

Hydrogen generation through thermal chemical water splitting technology has recently received increasingly international interest in the nuclear hydrogen production field. Besides the main known sulfur-iodine (S-I) cycle developed by the General Atomics Company and the UT3 cycle (iron, calcium, and bromine) developed at the University of Tokyo, the thermal cycle based on metal oxide two-step water splitting methods is also receiving research and development attention worldwide. In this work, copper ferrite was prepared by the co-precipitation method and oxygen-deficient copper ferrite was synthesized through first and second calcination steps for the application of hydrogen production by a two-step water splitting process. The crystal structure, properties, chemical composition and δ were investigated in detail by utilizing X-ray diffraction (XRD), thermogravimetry (TG) and differential thermal analysis (DTA), atomic absorption spectrometer (AAS), ultraviolet spectrophotometry (UV), gas chromatography (GC), and so on. The experimental two-step thermal chemical cycle reactor for hydrogen generation was designed and developed in this lab. The hydrogen generation process of water splitting through CuFe2O4− δ and the cycle performance of copper ferrite regeneration were firstly studied and discussed. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis and characterization of the pyrochlore solid solutions, Y2Ti2− x Nb x O7− y , Lu2Ti2− x Nb x O7− y , Y2Ti2− x Ta x O7− y and Lu2TiTaO7− y (−0.4

Abstract: We have investigated in-reactor luminescence (IRL) from a silica glass at temperatures ranging from 100K to 250K. The IRL consists mainly of a broad emission band peaked at 2.7eV assigned to oxygen deficient centers produced in the silica glass under the in-reactor irradiation. The 2.7eV emission intensity linearly increased with the irradiation time and its increasing rate was larger for higher irradiation temperatures. However, this temperature dependence is inconsistent with that for the defect production rate and the cause is not clear at present. The initial intensity of the 2.7eV IRL band increases with temperature, showing an activation energy of ca 21meV. This value is much lower than those observed in the temperature dependence of the 2.7eV photoluminescence (PL) and the cathodeluminescence (CL) induced by 8keV electron irradiation. These results suggest that in IRL, some electrons excited to higher energy levels than the luminescence level are likely transferred to the luminescence state without thermal activation, resulting in a lower activation energy in their temperature dependence. [Copyright &y& Elsevier]

Abstract: A series of oxygen deficient perovskites Sr0.8Y0.2Co1−x Fe x O3−δ , has been prepared by solid state reaction in close ampoules. The structural study by transmission electron microscopy reveals the existence of extra reflection peaks resulting from ordering phenomenon of the oxygen anions. For this implies a modulated structure characterized by a vector such as in the Pm3m space group. Interestingly, the Fe introduction in Sr0.8Y0.2CoO3−δ broadens the ferromagnetic transition, increasing the onset. Despite a lack of metallic-like behavior, the mixed “Co1−x Fe x ” compounds exhibit negative magnetoresistance properties which magnitude increases as T decreases below to reach the best effect of in 7 T for Sr0.8Y0.2Co0.5Fe0.5O3−δ . [Copyright &y& Elsevier]

Single crystals of both Ba7Li3Ru4O20 and Ba4NaRu3O12 were grown from reactive molten hydroxide fluxes. Ba7Li3Ru4O20 is a 7L-layer perovskite-related phase resulting from the stacking of six [AO3] layers and one oxygen deficient [AO2] layer, thereby creating LiO4 tetrahedra in addition to the LiO6 octahedra and face-sharing Ru2O9 bi-octahedra formed from the [AO3] layers. The compound crystallizes in the space group R3¯ m with a=5.7927(1) A˚ and c=50.336(2) A˚, Z=3. Ba4NaRu3O12 crystallizes in the space group P63mc with lattice parameters of a=5.8014(2) A˚ and c=19.2050(9) A˚, Z=2. Ba4NaRu3O12 is identical to a previously reported neutron refinement structure. The magnetic properties of Ba7Li3Ru4O20 are also reported. [Copyright &y& Elsevier]

• Oxygen-deficient TiO 2 decorated carbon paper was demonstrated as an advanced MFC anode. • The introduced oxygen defects and hydroxyl groups guarantee fantastic MFC performance. • The TiO 2-x NRAs exhibits superior electrocatalytic activity and biocompatibility. • The power density of MFC was boosted by 2.6 times. A free-standing oxygen-deficient hydrogenated TiO 2 nanorod arrays decorated carbon paper (CP) electrode (TiO 2-x NRAs/CP) is fabricated by a facile thermal reduction approach and developed as a robust anode for microbial fuel cells (MFCs). The oriented 3D nanostructure provides a fast electron transportation pathway for the electron transfer and large accessible areas for bacterial colonization. Also, the introduction of oxygen defects into TiO 2 can further enhance its bio- and electrochemical activity as well as biocompatibility. Consequently, the MFCs with TiO 2-x NRAs/CP as anode delivers a maximum power density of 2576.3±33 mW m−2, which is much larger than the MFCs with pristine TiO 2 NRAs/CP and CP anode. This work demonstrates the first use of oxygen-deficient TiO 2 NRAs/CP as an advanced anode for MFCs and provides a new path for performance improvement for metallic oxide anode MFCs. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Abstract: We have prepared EuTiO3− δ epitaxial thin films on SrTiO3 (001) substrates by a pulsed laser deposition technique and examined their magnetic properties. By controlling the oxygen pressure and substrate temperature, EuTiO3− δ films are epitaxially grown on the substrates. The resultant films exhibit ferromagnetic behavior with Curie temperature of 5K. Such magnetic properties are similar to those for La- and Gd-substituted EuTiO3 single crystal, in which the Ruderman–Kittel–Kasuya–Yoshida (RKKY) interaction between localized spins of magnetic ions brings about the ferromagnetic ordering. [Copyright &y& Elsevier]