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To develop new inorganic multifunctional materials, a series of Yb3+/Er3+ doped precursor glasses (PGs) were fabricated through melt quenching technique, and a novel niobate transparent photoelectric glass ceramic (GC) was gained via controlled crystallization of PG. Compared with PG, the up-conversion (UC) luminescence performance is significantly increased in GC. Utilizing the temperature dependence of the emission intensity of Er3+ ions, the dual-mode optical temperature measurement is realized through fluorescence intensity ratio (FIR) methods. The ultimate absolute sensitivity (S a-max) and relative sensitivity (S r-max) based on the thermal/non-thermal coupling energy levels (TCELs/NTCELs) are 0.68 %K−1 and 0.85% K−1, respectively. Moreover, the single-layer capacitor made of GC can release energy density of 0.83 J/cm3 (@600 kV/cm) and power density of 210 MW/cm3. This work indicates that niobate transparent glass ceramics are expected to be applied in the optical thermometry and pulse energy storage field. [ABSTRACT FROM AUTHOR]

Rational design of semiconductor membrane photocatalyst with good mechanical flexibility and excellent photocatalytic activity is of significance for environmental remediation. Herein, flexible Ag@ZnO/TiO 2 fibrous membranes with hierarchical nanostructures were fabricated through combining a simple electrospinning method and subsequent hydrothermal reaction and photodeposition process. In the ternary nanocomposite, ZnO nanorods were firmly anchored onto TiO 2 nanofibers, while Ag nanoparticles were evenly decorated on the surface of both ZnO and TiO 2. Benefiting from the improved light absorption, large surface area, and effective charge separation, the resultant Ag@ZnO/TiO 2 membranes displayed superior photocatalytic degradation efficiency of 91.6% toward tetracycline hydrochloride within 1 h, and also exhibited prominent antibacterial activity with a 6.5 log inactivation of E. coli after 1 h simulated solar light exposure. Significantly, the membrane photocatalyst still preserved structural integrity and mechanical flexibility after utilization. This study provides an alternative approach for designing and synthesizing flexible TiO 2 -based membrane photocatalysts toward high-efficiency water purification. [ABSTRACT FROM AUTHOR]

Nanofibers of TiO 2 , CeO 2 , Y 2 O 3 -stabilized ZrO 2 and SrTiO 3 with length of a few micrometers and average diameters of 50–250 nm were fabricated by electrospinning, the structures and morphologies were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscope, the stoichiometry by Raman spectrum and X-ray photoelectron spectroscopy. And the optimum electrospinning conditions and calcination temperatures were determined. [ABSTRACT FROM AUTHOR]

In recent years, water pollution caused by organic pollutants and antibiotic residues has become increasingly serious, posing a serious threat to human health and ecosystems. In this paper, Co–BiVO 4 /Bi 2 O 3 heterojunction was successfully prepared by electrospinning of Co3+ doped monoclinic BiVO 4 nanofibers and Bi 2 O 3. The photocatalytic degradation of chlortetracycline hydrochloride (CTC·HCl) and 2-mercaptobenzothiazole (MBT) in water was tested by simulating visible light conditions. The degradation efficiency of CTC·HCl by 3Co–BiVO 4 /Bi 2 O 3 -0.8 reached 90.5 % within 30 min, and the degradation rates were 3.93 and 7.06 times that of BiVO 4 and Bi 2 O 3 , respectively. At the same time, the degradation efficiency of MBT by 3Co–BiVO 4 /Bi 2 O 3 -0.8 reached 97.7 % within 40 min, and the degradation rates were 8.93 and 41.80 times that of BiVO 4 and Bi 2 O 3 , respectively. In addition, the photocatalytic performance of the catalyst and potassium persulfate (PS) co-system on pollutants was investigated. When 0.5 mM PS and a small amount of 3Co–BiVO 4 /Bi 2 O 3 -0.8 catalyst were added, the degradation efficiency of CTC·HCl and MBT could reach 87.6 % and 92.8 % in a short time. Furthermore, the work function and difference of the material were calculated by density functional theory (DFT), and the charge transfer mechanism of the p-n heterojunction was further determined. Finally, the intermediate products, degradation pathways and reaction mechanisms of MBT degradation were analyzed in detail by high performance liquid chromatography-mass spectrometry (HPLC-MS). Therefore, this study provides a potential effective way for the treatment of water pollution. [Display omitted] [ABSTRACT FROM AUTHOR]

In recent years, water pollution caused by organic pollutants and antibiotic residues has become increasingly serious, posing a serious threat to human health and ecosystems. In this paper, Co–BiVO 4 /Bi 2 O 3 heterojunction was successfully prepared by electrospinning of Co3+ doped monoclinic BiVO 4 nanofibers and Bi 2 O 3. The photocatalytic degradation of chlortetracycline hydrochloride (CTC·HCl) and 2-mercaptobenzothiazole (MBT) in water was tested by simulating visible light conditions. The degradation efficiency of CTC·HCl by 3Co–BiVO 4 /Bi 2 O 3 -0.8 reached 90.5 % within 30 min, and the degradation rates were 3.93 and 7.06 times that of BiVO 4 and Bi 2 O 3 , respectively. At the same time, the degradation efficiency of MBT by 3Co–BiVO 4 /Bi 2 O 3 -0.8 reached 97.7 % within 40 min, and the degradation rates were 8.93 and 41.80 times that of BiVO 4 and Bi 2 O 3 , respectively. In addition, the photocatalytic performance of the catalyst and potassium persulfate (PS) co-system on pollutants was investigated. When 0.5 mM PS and a small amount of 3Co–BiVO 4 /Bi 2 O 3 -0.8 catalyst were added, the degradation efficiency of CTC·HCl and MBT could reach 87.6 % and 92.8 % in a short time. Furthermore, the work function and difference of the material were calculated by density functional theory (DFT), and the charge transfer mechanism of the p-n heterojunction was further determined. Finally, the intermediate products, degradation pathways and reaction mechanisms of MBT degradation were analyzed in detail by high performance liquid chromatography-mass spectrometry (HPLC-MS). Therefore, this study provides a potential effective way for the treatment of water pollution. [Display omitted] [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) and their derivatives as electrode materials for energy storage and conversion are intriguing. However, the in-situ uniformly and firmly growing metal-organic framework materials directly on conductive substrates is limited and still challenging. Herein, an effective strategy is presented by constructing a ribbonlike Co 3 O 4 nanoarrays that derived from zeolite imidazole framework (ZIF) on carbon cloth as "fixed piles" for the in-situ solvothermal synthesis of Ni-MOF nanosheets. As a result, the Ni-MOF nanosheets closely distribute on the surface of the carbon cloth with fluffy structure, which favors exposure of more active sites and rapid diffusion of electrolyte ions. The as-fabricated integrated composite electrode (Co 3 O 4 @Ni-MOF) delivers a good specific capacitance of 1416 F/g at the current density of 1 A/g, superior to the individual Co 3 O 4 (410 F/g) and Ni-MOF electrode (690 F/g). Moreover, the specific capacitance can be kept at 90% of its original value after 3000 cycles. Based on these advantages, a hybrid supercapacitor fabricated by the Co 3 O 4 @Ni-MOF electrode and activated carbon (AC) shows prominent energy density of 68.6 Wh kg−1 at the power density of 510 W kg−1, and excellent cycling stability (about 12% capacitance loss after 5000 charge-discharge cycles). [ABSTRACT FROM AUTHOR]

In this study, the corrosion resistance and thermal shock resistance of Sc x Ta 0.5−x YSZ (x = 0, 0.05, 0.25, 0.45, and 0.5 mol%) coatings prepared via the solid-state reaction method were compared and evaluated. The corrosion resistance and thermal shock resistance of different materials were analyzed using X-ray diffraction, field-emission scanning electron microscopy, energy-dispersive spectrometry, and stereomicroscopy. Results show that Sc 0.25 Ta 0.25 YSZ has the best corrosion resistance and thermal shock resistance among all tested materials and the number of thermal cycles exceeds 679 at 1150 °C. The excellent properties can be attributed to the small ionic radius of Sc3+ in the Sc 0.25 Ta 0.25 YSZ composite, which gives the material good thermal stability at high temperatures. In the corrosion process, Sc 0.25 Ta 0.25 YSZ forms highly stable zirconia tantalum, affording good corrosion resistance. [ABSTRACT FROM AUTHOR]

In this work, ferric ceria nanofibers (FC NFs) with different iron contents were successfully fabricated through electrospinning followed by calcination at 550 °C. The resultant FC NFs were blended with multi-walled carbon nanotubes (MWCNT@FC) and utilized to modify the glassy carbon electrode (GCE) for uric acid (UA) detection. The XRD patterns revealed that FCs NFs have cubic lattice structure. The Raman and X-ray photoelectron spectroscopy (XPS) were confirmed the presence of oxygen vacancies with Fe(II)/Fe(III) and Ce(III)/Ce(IV) chemical states of the surface ions. The surface morphology was investigated through scanning electron microscopy (SEM) and particle size analysis was performed using transmissions electron microscopy (TEM). The electrochemical properties of MWCNT@FC NFs were evaluated through cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods under varied conditions. The results demonstrated the crucial effects of Ce/Fe molar ratio on the electrocatalytic performance due to the sufficient oxygen vacancies originating from the incorporation of Fe3+ ions into ceria (CeO 2). Furthermore, blending with 70 wt% MWCNT (MWCNT70@FC) gave rise to a significant improvement on the electrical conductivity. The MWCNT70@FC-2 modified GCE composite with Ce/Fe molar ratio of 1:1 displayed high performance towards UA detection at 6.0 pH.The detection limit of 0.3 μM was achived with wide linear range from 0.5 μM to 500 μM. The MWCNT70@FC-2 demonstartedadequate stability and reproducibility for urice acid detection. The high selectivity and accuracy was further established for prepared MWCNT@FC-2 composite sensor by detecting UA in real biological samples. The obtained results were precise and reproducible. [ABSTRACT FROM AUTHOR]

Abstract Generally, glass-ceramics possess better properties than their parent glasses. Here, we successfully prepared Sr2+/Y3+ co-doped MgO-Al 2 O 3 -SiO 2 -based glasses and transparent glass-ceramics. The results revealed that the glass stability for the parent glasses increased and then decreased as the SrO content increased, showing the opposite trend of crystallinity under the same heating conditions. Structurally, the bonding strength between the structural groups showed the same trend as the glass stability. In addition, the main crystalline phases in the glass-ceramics were cordierite (Mg 2 Al 4 Si 5 O 18), magnesium aluminum silicate (Mg 2 Al 4 Si 5 O 18) and strontiumosumilite (Sr 0.91 Mg 2 (Al 5.82 Si 9.18 O 30)). Regarding the microstructures of the glass-ceramics, spherical or near-spherical grains appeared. As for the physical properties of the glass-ceramics, the density initially increased and then decreased, while the molar volume followed the opposite trend with the increasing SrO concentration. Analysis of the mechanical properties showed that the Vickers hardness, bending and compressive strength of the glass-ceramics first decreased and then increased with the variation of the SrO and Y 2 O 3 contents. [ABSTRACT FROM AUTHOR]

The porous ceramics were prepared by directly sintering of lead-zinc mine tailings and fly ash as the raw materials without any additional sintering and foaming agent. The effects of fly ash addition on the crystalline phases, pore structure, physical–chemical porosities and mechanical strength were investigated. The results showed that the bulk density decreased firstly and then increased while the porosity and water absorption presented the opposite tendency with the increase of fly ash content. Meanwhile, the chemical stability improved and the flexural strength had the same variation tendency of the bulk density. The phase evolution of sample with 60 wt% fly ash addition indicated that anorthite phase was formed at low temperature (1000 °C). The thermal behavior illustrated that the foaming process was initiated by the reaction of internal constituents in the lead-zinc mine tailings. Different pore structures indicated different foaming mechanisms that probably occurred at different temperatures. The porous ceramics with 60 wt% fly ash addition exhibited excellent properties, including bulk density of 0.93 g/cm 3 , porosity of 65.6%, and flexural strength of 11.9 MPa. [ABSTRACT FROM AUTHOR]