Search

ZIF-8, a metal–organic framework that has significant benefits such as a substantial specific surface area, abundant active sites, and high porosity, has extensive application in environmental remediation. However, ZIF-8 is powdery and easily agglomerated, making it difficult to separate ZIF-8 from aqueous solutions and thus limiting its practical application in wastewater treatment. In this work, sodium alginate was chosen as a gel matrix, and CaCl2 as a cross-linking agent to form a calcium cross-linked MOF gel material (ZIF-8/SA). The batch adsorption investigations demonstrated that the saturated adsorption capacities of ZIF-8/SA in single Mn2+ pollution solution and Mn–Cu–Cd composite pollution solution are 179.86 mg g−1 and 101.86 mg g−1, respectively. Specifically, the adsorption of Mn2+ followed the Langmuir model and exhibited monomolecular layer adsorption. Furthermore, the adsorption of Cu2+ and Cd2+ followed the quasi-first-order kinetic model, which is primarily physical adsorption. The adsorption order of ZIF-8/SA for contaminants in the adsorption process is as follows: Cu2+ > Cd2+ > Mn2+. The SEM-EDS, FT-IR, and XPS studies revealed that the adsorption mechanism of ZIF-8/SA mostly involves ion exchange, coordination of carboxyl/hydroxyl/amino groups, and electrostatic attraction. To summarize, the experimental findings of this study demonstrate that the synthetic ZIF-8/SA hydrogel has promising applications for practical pollution treatment. [ABSTRACT FROM AUTHOR]

HZSM-5 zeolite modified by rare earth was prepared with ion exchange method in the study. The effects of different types of rare earth elements, modification temperatures, pH, and rare earth contents on structural stability of the as-prepared zeolite were investigated. The as-prepared zeolite was characterized by XRD, SEM and FT-IR spectroscopy. The characterization results showed that the crystal structure of the zeolite was not changed by the modification of rare earth, which was evenly distributed on the surface or in the pore channel of zeolite. Sm/HZSM-5 zeolite with the highest structural stability was obtained under the following modification conditions: 2% rare earth Sm, modification temperature of 70 °C, 2 h of ion exchange, and pH 3. [ABSTRACT FROM AUTHOR]

In the study, MgAl binary water talc (MgAl-CO3-LDHs) was firstly synthesized by a steady-state co-precipitation method and then characterized by XRD, SEM and ICP-OES methods. The effects of n(Mg2+)/n(Al3+) in mixed salt solutions, pH and roasting temperature on the properties of MgAl-CO3-LDHs were mainly explored. The optimal adsorption condition of VO3- on MgAl-CO3-LDHs was determined as synthesis temperature of 25 °C, n(Mg2+)/n(Al3+) ratio of 3:1, pH 8 ± 0.1 and roasting temperature of 517 °C. The adsorption characteristics of MgAl-CO3-LDHs on VO3- were better fitted with Langmuir's isothermal equation and quasi-secondary kinetic equation. The adsorption mechanism was close to the monolayer adsorption with a saturated adsorption capacity of 53.73 mg/g. [ABSTRACT FROM AUTHOR]

In the study, MgAl binary water talc (MgAl-CO3-LDHs) was firstly synthesized by a steady-state co-precipitation method and then characterized by XRD, SEM and ICP-OES methods. The effects of n(Mg2+)/n(Al3+) in mixed salt solutions, pH and roasting temperature on the properties of MgAl-CO3-LDHs were mainly explored. The optimal adsorption condition of VO3- on MgAl-CO3-LDHs was determined as synthesis temperature of 25 °C, n(Mg2+)/n(Al3+) ratio of 3:1, pH 8 ± 0.1 and roasting temperature of 517 °C. The adsorption characteristics of MgAl-CO3-LDHs on VO3- were better fitted with Langmuir's isothermal equation and quasi-secondary kinetic equation. The adsorption mechanism was close to the monolayer adsorption with a saturated adsorption capacity of 53.73 mg/g. [ABSTRACT FROM AUTHOR]

Eu3+ activated red phosphors based on the CaY x (MoO 4) 1.5x+1 (x = 0.2, 0.4, 0.6, 1, 2) as host materials were synthesized by using a combustion method. XRD analysis demonstrated that the synthesized samples matched with the standard card CaMoO 4 (JCPDS NO.77-2239) belonging to the tetragonal of the I4 1 /a space group. All samples showed several narrow sharp emission peaks under 393 nm n-UV excitation, the strongest of which was at 618 nm attributed to the 5D 0 →7F 2 transition of Eu3+. The optimal composition of the host was found to be CaY 0.6 (MoO 4) 1.9 (hereafter referred to as CYMO). After doping Sm3+ into CYMO:Eu3+ phosphor, the absorption peaks of Eu3+ at 393 and 464 nm were broadened, and the peak intensity was also significantly higher than that of single-doped Eu3+. The energy transfer phenomenon between Sm3+ and Eu3+ was discovered by the excitation and emission spectra in CYMO:Eu3+,Sm3+ phosphors, and verified by the fluorescence lifetime of Sm3+ ions in the phosphors. The energy transfer mechanism between Sm3+ and Eu3+ is a dipole-dipole interaction, where the energy transfer efficiency in CYMO phosphor doped with 13% Eu3+ and 3% Sm3+ is 17.9%. The CIE coordinate and color purity were calculated as (x = 0.6598, y = 0.3388) and 93.72%, which indicated that the CYMO:13%Eu3+,3%Sm3+ phosphor is a red phosphor with excellent performance for potential application in n-UV light excited w-LEDs. [ABSTRACT FROM AUTHOR]

With Miyi diatomite as the carrier and ferric nitrate as the modification agent, nano-micron vanadium adsorbent was prepared in the study. Then the adsorption properties of the prepared adsorbent were characterized by XRD, XRF, SEM, and ICP-OES analysis. The effects of adsorption time, initial pH value and initial vanadium concentration on VO3− adsorption performance were studied and the adsorption mechanism was discussed. The adsorption of VO3− on Miyi diatomite was significantly improved by the modification with ferric nitrate. The adsorption process of VO3− on nano-micron vanadium adsorbent was in accordance with Langmuir isothermal equation and quasi-second-order kinetic model. The saturated adsorption capacity was 43.38 mg/g. The adsorption capacity was higher in the weak acid environment and peaked at pH = 4. [ABSTRACT FROM AUTHOR]

In this study, the loaded diatomite was prepared with Changbai Mountain diatomite as the carrier according to different Fe/Al molar ratios. The structure and adsorption of the above materials were characterized by XRD, SEM, and ICP-OES. The effects of Fe/Al molar ratio, adsorption time, initial concentration of V(V), and the initial pH value of the solution on the adsorption performance of loaded diatomite were explored. The diatomite loaded with Fe/Al compounds could significantly improve the removal efficiency of V(V), and the removal efficiency of loaded diatomite prepared according to a Fe/Al molar ratio of 1:3 was better. Reaction equilibrium time is 24 h and the pseudo second-order kinetic equation can better describe the adsorption kinetic behavior of V(V) on loaded diatomite. When the initial concentration of V(V) increased from 15.85 mg/L to 122.5 mg/L, the unit adsorption capacity and removal rate of V(V) by loaded diatomite increased continuously. The adsorption behavior of V(V) on loaded diatomaceous earth belongs to the chemical adsorption via the multi-molecular layer, which is consistent with the Freundlich isotherm adsorption model. A weak acid environment is beneficial to the adsorption behavior of V(V) on loaded diatomaceous earth and the strong alkaline environment should be avoided. [ABSTRACT FROM AUTHOR]

The nanoakaganeite (β-FeOOH) was synthesized by the hydrothermal method in the study. The structural characterization and adsorption investigation of the produced materials were performed with powder X-ray diffractometer (XRD), scanning electron microscope (SEM), and inductively coupled plasma optical emission spectrometer (ICP-OES). Moreover, the influences of hydrothermal time, Fe3+ concentration, and hydrothermal temperature on the product structure and chromium adsorption were investigated. In addition, the influence of initial Cr(VI) concentration on chromium adsorption was investigated. The investigation results confirmed the optimal synthesis conditions of β-FeOOH as follows: 72 h hydrothermal reaction, 0.20 M Fe3+, and hydrothermal temperature at 70 °C. The as-synthesized β-FeOOH was spindle-shaped akaganeite. When the initial Cr(VI) concentration increased from 9.91 mg/L to 99.47 mg/L, the adsorption capacity increased and Cr(VI) removal rate decreased. Cr(VI) adsorption on β-FeOOH was a single-molecule layer chemical adsorption, conforming to the Langmuir adsorption model. The maximum saturation adsorption was 16.35 mg/g. [ABSTRACT FROM AUTHOR]

316L stainless steel spherical powder for 3D printing and metal injection molding was prepared by supersonic laminar flow atomization. Then the as-prepared samples were characterized by XRF, XRD, SEM, and an oxygen/nitrogen analyzer. Characterization results indicated that the prepared 316L spherical powder had the high sphericity, high tap density, low oxygen content, small particle size and narrow size distribution and were applicable to 3D printing and MIM. [ABSTRACT FROM AUTHOR]

Nanosized magnesium hydroxide (Mg(OH)2) with sheet and flower structure were prepared via precipitation reaction between magnesium chloride and alkaline precipitant, such as ammonium hydroxide, sodium hydroxide and urea. The structure and morphology of as-prepared samples were characterized through X-ray diffraction and scanning electron microscopy. Effect of precipitants and surface modifier on morphology and size of nano-Mg(OH)2were investigated. Heat-resistance of Mg(OH)2in polymer was discussed by thermogravimetry-differential thermal analysis. Mg(OH)2nanostructure present superior morphology and heat-resistance with NH4OH-NaOH as precipitant and 3mol% acrylic acid as surface modifier. [ABSTRACT FROM PUBLISHER]

In this study, a series of white light-emitting NaSrVO 4 :Dy3+ phosphors with La3+ co-doping were produced by a combustion method. The configurations of the as-prepared NaSrVO 4 :Dy3+ and NaSrVO 4 :Dy3+, La3+ specimens are consistent with the standard phase of NaSrVO 4. The impacts of the Dy3+ concentration and La3+ co-doping on the luminescence characteristics of NaSrVO 4 : Dy3+ phosphors were explored. The specimens excited by near-ultraviolet light displayed emission peaks at 580 (yellow) and 484 nm (blue), which were ascribed to the 4F 9/2 → 6H 13/2 and 4F 9/2 → 6H 15/2 transitions of the Dy3+ ions, respectively. The white light was manufactured by these two emissions from the NaSrVO 4 : Dy3+ phosphor. Photoluminescence studies demonstrated that the La3+ co-doping efficiently improved the luminescence characteristics of the NaSrVO 4 : Dy3+ phosphor. These results suggest that the NaSr 0.9425 VO 4 : 0.05Dy3+, 0.0075La3+ phosphors excited by near-ultraviolet are promising materials for white light-emitting diodes. [ABSTRACT FROM AUTHOR]

High mineralization activity is a crucial requirement in bone tissue engineering. In this study, a novel calcium citrate compounded amorphous calcium phosphate (CAP)/polyurethanes (PUs) composite porous 3D scaffold was developed by in situ polymerization via gas foaming method. The physical and chemical properties were characterized and discussed. The results showed that the HDI can react mildly with hydroxyl (–OH) groups of PEG, while gas foaming action was caused by the release of CO2 occurred in the reactive process, resulting in a uniform porous structure of PUs scaffold. The porosities of the synthetic PEGCAP porous scaffolds are all above 70% with high interconnectivity, while the porosity decreased 27% with increasing CAP to 40%. Furthermore, the mechanical properties of porous scaffolds enhanced about 16 times after addition of CAP. After immersing in simulated body fluid (SBF), the surface structure of the porous scaffold kept stable, and surface deposits formed, indicating that the porous scaffold has good mineralization activity. In addition, the in vitro cells proliferation assay confirms the excellent bioactivity of PEGCAP porous scaffolds. [ABSTRACT FROM AUTHOR]

Ytterbium-doped titanium dioxide (Yb-TiO 2 )/diatomite composite materials with different Yb concentrations were prepared by sol–gel method. The phase structure, morphology, and chemical composition of the as-prepared composites were well characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), and ultraviolet–visible (UV–vis) diffuse reflection spectroscopy. The XRD and Raman spectroscopy analysis indicated that the TiO 2 existed in the form of pure anatase in the composites. The SEM images exhibited the well deposition and dispersion of TiO 2 nanoparticles with little agglomeration on the surfaces of diatoms. The UV–vis diffuse reflection spectra showed that the band gap of TiO 2 could be narrowed by the introduction of Yb species, which was further affected by doping concentration of Yb. The photocatalytic activity of synthesized samples was investigated by the degradation of methylene blue (MB) under UV light irradiation. It was observed that the photocatalytic degradation followed a pseudo-first-order kinetics according to the Langmuir–Hinshelwood model. Compared to TiO 2 and TiO 2 /diatomite, the Yb-TiO 2 /diatomite composites exhibited higher photocatalytic activity toward degradation of MB using UV light irradiation. [ABSTRACT FROM AUTHOR]

The heavy metals and organic substances has deterioration of the ecosystem, resulting in serious environmental pollutions, thus urgent solutions need to be developed in treating these waste water problems. Functional compounds modified 3D polyurethane foams, with high surface to volume ratio has paid much attentions due to their high efficiency of absorption capability. In this study, polyethyleneimine (PEI) was used to incorporated into polyurethane foam (PUF) loaded with sodium carboxymethylcellulose (SCMC), resulting in a cross-linked, 3D interconnective porous polyurethane foam (PCPUF). The results of adsorption experiments demonstrated that PCPUF exhibited a strong adsorption capacity for both MO and Cd2+, with corresponding maximum adsorption capacity of 415.198 mg/g (at 328 K, pH 7) and 166.48 mg/g (at 343 K, pH 7), respectively. Furthermore, the results of cyclic adsorption experiments showed that the removal rates of MO and Cd2+ after five cycles are 90 % and 85 %, respectively, indicating that PCPUF has a good recyclability. Therefore, 3D porous polyurethane foams show promise as an effective adsorbent for removing metal ions and organic substances. [Display omitted] [ABSTRACT FROM AUTHOR]

As an important industrial catalytic material, ZSM-5 zeolites are still facing durability issues. The long-time exposure among high temperature steam during the catalytic reaction becomes the main drawback for ZSM-5 zeolite application in industry. In this study, we investigate the effects of rare-earth-ions (La, Ce, Nd, Sm, Gd, and Dy) doping on the catalytic activity and hydrothermal stability of ZSM-5 zeolites based on density functional theory. The results demonstrate that the introduced rare-earth-ions prefer to adsorb on the top of Al atom (T12 site). The Milliken charge transfer and electron density difference confirm the strong electrostatic interactions between the ZSM-5 zeolites and rare-earth-ions. The activation reaction of butene is investigated to estimate the catalytic activity of rare-earth-ion doped ZSM-5. The results demonstrate that La and Sm doped ZSM-5 zeolites exhibit superior performance on butene activation. In addition, rare-earth-ions decoration show enhanced sodium tolerance performance with decreased affinity toward Na during the catalytic process. This study demonstrated that the modification of rare-earth-ions can effectively improve the hydrothermal stability and catalytic activity of ZSM-5 zeolites. [ABSTRACT FROM AUTHOR]

As a new zero-optic luminescent material, carbon quantum points are widely focused and sustained, and many researchers are trying to use simple and fast methods and stable, good carbon sources to be prepared with a good fluorescent properties of carbon quantum dots. In this paper, carbon quantum dots were synthesized by solvothermal method with vanillin as carbon source, and the effects of solvothermal temperature and time on the luminescence properties of carbon quantum dots were explored. Then, carbon quantum dots were characterized by X-ray diffraction analysis, transmission electron microscopy analysis, infrared spectrum analysis, fluorescence spectrum analysis. Research results showed that ethanol solvent with vanillin as a carbon source by solvothermal method could synthesize good water soluble carbon quantum dots with weak crystallization, and its size was about 10 nm. This carbon quantum dots had obvious excitation wavelength dependence and produce blue light, which had potential application value in ion fluorescence probe or cell labeling. [ABSTRACT FROM AUTHOR]

Adsorption is a simple and efficient phosphorus removal method used to control the eutrophication of water bodies. A simple and gentle atmospheric pressure hydrothermal method by adjusting the dosage of ammonium chloride and sodium hydroxide was used to synthesize amorphous, monoclinic, and tetragonal zirconia nano-powders with high specific surface areas (383.91 m2/g, 330.01 m2/g, and 234.36 m2/g) and particle size of about 40 nm for phosphate adsorption. When pH = 6.3, the phosphate adsorption capacity of the amorphous monoclinic phase and the tetragonal phase respectively reached 102.58 mg P/g, 68.11 mg P/g, and 37.25 mg P/g and the adsorption process of the three crystal forms of zirconia powders conformed to the Langmuir adsorption model. In the first 2 min of rapid adsorption, amorphous zirconia completed 76.23% of the adsorption process and the monoclinic phase also completed more than 60%. The adsorption process of the three crystal forms of zirconia was completed within 240 min and conformed to the pseudo-second-order kinetic model. Their adsorption characteristics of the three crystal forms of zirconia decreased with the increase in pH. While the pH was above than the isoelectric point of the solution, the adsorption capacity was significantly reduced. The large specific surface area and high hydroxyl content of the zirconia nano-powder made a great contribution to the adsorption process. [ABSTRACT FROM AUTHOR]

Via wet chemical method with organic assistant, ZnS:Cu/ZnS core/shell structure was prepared. X-ray diffraction measurements showed that ZnS:Cu was formed with zinc blende structure, and ZnS shell growth on the surface was indicated through a red-shift in the UV-Vis absorption spectra with increasing particle size. The emission peak at about 510 nm was observed, which should be assigned to recombination of an electron from the shallow delocalized donor levels at thet2level of Cu2+centers. As passivation layer, effect of ZnS shell on luminescence intensity and lifetime of ZnS:Cu were investigated. Comparing with uncoated ZnS:Cu, ZnS shell really enhanced the luminescence intensity and lifetime significantly, which resulted from the reduction of nonradiative recombination sites. [ABSTRACT FROM AUTHOR]

The stability of phosphors and matrix under humid conditions and elevated temperatures is essential for the stable performance of light-emitting diodes. We synthesized a series of NaYSiO 4 : x Eu3+ (x = 0.00–0.14) phosphors via a sol-gel reaction. The NaYSiO 4 crystallizes in a hexagonal structure (space group P63/m) with a bandgap value of 4.60 eV. In this lattice, doped Eu3+ occupied the center of non-inversion symmetry. Under the optimal 394 nm excitation, the NaYSiO 4 :0.04Eu3+ sample showed a strong red emission at 618 nm with a high color purity of up to 94.98 %. Impressively, it exhibited high thermal stability (523 K, > 50 %, ∆ E = 0.24089 eV) and moisture resistance. Due to the protection of the stable coordination environment provided by cyclic Si-O-Si bands and strong binding energy, it retained 90.2 % of its original intensity after exposure under the relative humidity of 85 % at 85 °C for 240 h. Furthermore, this red phosphor was packaged into a cold white light-emitting diode with Commission International de l′Eclairage (0.3250, 0.3364). From the perspective of host lattice structure, this work provides a new strategy to withstand luminous degradation under humid and warm conditions. • NaYSiO 4 :Eu3+ exhibits excellent moisture resistance and thermal stability. • NaYSiO 4 :Eu3+ is an effective red-emitting component with high color purity. • Eu3+ occupies non-inversion symmetry sites protected by Si-O-Si bands. [ABSTRACT FROM AUTHOR]

To improve the luminescence property of Sm3+ in Y 2 Mo 3 O 12 , partial Ca2+-F- co-substituted Y 2 Mo 3 O 12 :Sm3+ phosphor, namely Y 2- x Ca x Mo 3 O 12- x F x :Sm3+, was prepared using a solid-state method. The effect of introducing Ca2+-F- ion pairs on structure and luminescence properties of Y 2 Mo 3 O 12 :Sm3+ was studied in depth. XRD patterns not only manifested that all as-prepared Y 2- x Ca x Mo 3 O 12- x F x :Sm3+ samples had standard Y 2 Mo 3 O 12 structure, but also indicated the introduction of Ca2+-F- ion pairs did not cause the change of crystal structure. Under the near ultraviolet excitation of 404 nm, the emission peaks of Y 2 Mo 3 O 12 :Sm3+ were located at 567 nm, 605 nm and 652 nm, respectively, resulting from the 4f→4f electron transitions of Sm3+ ions. Furthermore, the luminescence intensity of Sm3+ was obviously enhanced through the co-substitution of Y3+-O2- ions with Ca2+-F- ions in Y 2 Mo 3 O 12 structure, and the chromaticity coordinates moved towards red region, which due to the environmental effect of crystal field around Sm3+. Besides, the red LED device was manufactured for suitable chromaticity parameters. All results indicated that the as-prepared Y 1.84 Ca 0.06 Mo 3 O 11.94 F 0.06 :0.10Sm3+ red-emitting phosphor could become a promising candidate for application of white light-emitting diodes and plant illumination. [ABSTRACT FROM AUTHOR]

A series of β -Ca 3 (PO 4) 2 type single-component Ca 19 Zn 2 (PO 4) 14 :Dy3+, M+ (M = Li, Na and K) white-emitting phosphors were synthesized via a high-temperature solid-state reaction method, where alkali metal ions (M+) co-doped as charge compensator into the Ca 19 Zn 2 (PO 4) 14 :Dy3+ phosphor was aimed at improving the overall luminescence. The influences of synthesis temperature and the M+ introduction on both structure and luminescence property were thoroughly studied. X-ray diffraction patterns verify that the as-prepared phosphors attain the standard Ca 19 Zn 2 (PO 4) 14 phase without impurities. Photoluminescence peaks at 484 nm and 575 nm (originating from the 4F 9/2 → 6H 15/2 and 4F 9/2 → 6H 13/2 electron transitions of Dy3+ ions) were produced for all samples with an excitation of 386 nm, which then combined to emit white light. The luminescence intensities of Ca 19 Zn 2 (PO 4) 14 :Dy3+ were dramatically improved through co-doping with M+ into the phosphor structure. These results demonstrate the promising application prospects of Ca 19 Zn 2 (PO 4) 14 :Dy3+, M+ white-emitting phosphors in white light-emitting diodes. [ABSTRACT FROM AUTHOR]

In this study, porous composite materials were prepared from calcium citrate (CC) and polylactic acid (PLA). Scanning electron microscopy (SEM) showed that the prepared composite materials had the uniformly pore distribution and suitable pore size for bone tissue engineering and displayed proper mechanical properties. As confirmed in X-ray diffraction (XRD), SEM and thermal analysis, the lipophilic property of CC had the improved compatibility and uniform dispersion in the PLA matrix. In addition, the prepared materials showed the high mineralization activity and the ability to guide the formation of apatite since the hydrophilicity of CC improved the wettability of the composite materials. In vivo animal experiments showed that the material was nontoxic and had good biocompatibility. Furthermore, the synergic degradation of CC and PLA effectively neutralized the acidic environment, thus preventing partial inflammation caused by acidic products. CC/PLA composite materials provide a promising new bone repair material for bone tissue engineering. [ABSTRACT FROM AUTHOR]

[Display omitted] • The interlayer B B bond in BL-α + borophene exhibits rhythmic expansion and contraction upon metal-ion storage. • BL-α + borophene manifests low adhesion energy to Ag (1 1 1) substrate compared with its monolayer counterpart. • The flexible interlayer bonding enables a remarkable theoretical capacity of 1351.6 mAh/g for both of Li-ion and Na-ion anodes. • BL-α + borophene displays moderate diffusion barriers for metal-ions. The fabrication of bilayer borophene presents an alternative approach to tackle the challenges related to thermodynamic stability and the detachment of monolayer borophene from the metal substrate, which currently restrict its practical application. However, recent theoretical investigations have revealed that the structural arrangement of the most energetic free-standing bilayer borophene, denoted as BL-α+ borophene, is different from the configuration observed experimentally (Nat. Mater. 2022, 21, 35–40). Herein, the effects of introducing an additional stratum of borophene on the electronic properties, mechanical performance, adherence capabilities towards Ag (1 1 1), and electrochemical performance as an anode material for alkali-ions batteries has been thoroughly examined. The results demonstrate that free-standing BL-α+ borophene manifests a reduced energy adhesion (E adh) of −0.059 eV Å−2 when contrasted with its monolayer counterpart. Furthermore, the interlayer B-B bonding exhibits a breath-like dilatation and contraction behavior during metal-ion adsorption/desorption, leading to remarkable theoretical capacities of 1351.6 mAh/g for Li-ion anodes, 1351.6 mAh/g for Na-ion anodes, and 450.53 mAh/g for K-ion anodes, accompanied by moderate diffusion barriers of 0.58 eV, 0.34 eV, and 0.23 eV for Li, Na, and K ions, respectively. These results provide valuable insights into the application of borophene-based electrode materials that exhibit improved stability through a "self-stacking" mechanism. [ABSTRACT FROM AUTHOR]

As a promising candidate for the next generation of new anode materials, the modification and optimization of silica-based anode materials are significant. Using chitosan (CS) as the carbonaceous precursor, the N-containing Si@C microcapsules were prepared by emulsification cross-linking combined with high-temperature pyrolysis method. The microcapsule structure offers additional space for nano-Si and effectively enhances the electrochemical properties of the anode. Moreover, optimizing the CS:Si ratio is advantageous in achieving a synergistic effect between silicon and carbon. When CS:Si = 4:1, the first specific capacity was 762.78 mAh/g and the retention rate was 69.27 % after 100 cycles. To further enhance the material properties, urea was added to a ratio of CS:Si = 4:1 as an N supplement for elemental doping modification. The specific capacity of the anode had a positive correlation with N content within a certain range. As the N content increases, the pyridine-N content and density of C vacancies also increase, which improves the storage form and diffusion path of Li+. When 0.75 g urea was added, the first reversible specific capacity reached 1108.88 mAh/g and the retention rate was 92.41 % after 100 cycles. This work offers environmentally friendly and safe methods, as well as a new modification concept for N-doped microsphere-encapsulated silicon-carbon composites. • Microcapsule structure provides additional physical buffer space. • Chitosan as biomass polymers containing N. • Nanosilicon diffusely distributed inside the carbon shell. • The increase of N can optimize the storage form and diffusion path of Li+. [ABSTRACT FROM AUTHOR]

A novel material Bi1-xGdx-BTC was obtained in situ via the solvothermal method. The effects of Gd3+ substitution on the Bi-BTC structure and photocatalytic properties of Bi1-xGdx-BTC were investigated. A standard Bi-BTC structure was observed in the X-ray diffraction spectra of the Bi1-xGdx-BTC(x ≤ 0.07). However, some diffraction peaks were changed when the x is more than 0.07 due to the different ion radius. The developed Bi1-xGdx-BTC samples exhibited higher photocatalytic activity than the pure Bi-BTC material. In RhB degradation experiments, the Bi1-xGdx-BTC(x = 0.03 and x = 0.05) materials show degradation efficiency conversion of 71% within 60 min under visible light. The high photodegradation efficiency of Bi1-xGdx-BTC could be ascribed to efficient charge transfer between Bi(III) ions and Gd(III) ions. Moreover, an active species trapping experiment confirmed that photo-generated ·O2- and ·OH is the major species involved in RhB degradation. [ABSTRACT FROM AUTHOR]

With sugarcane bagasse as the carrier and iron chloride hexahydrate (FeCl3·6H2O) as the iron source, Fe3O4@C materials were prepared in this study. Then the adsorption properties of the prepared adsorbents were characterized by XRD, SEM and VSM analysis. The effects of adsorption time, initial pH value and initial methylene blue concentration on methylene blue adsorption performance were studied and the adsorption mechanism was discussed. The Fe3O4@C materials synergistically exerted the good adsorption capacity and magnetic properties. The adsorption process of methylene blue on Fe3O4@C adsorbent was in accordance with Freundlich isothermal equation and quasi-second-order kinetic model. The saturated adsorption capacity in the experiment of Fe3O4@C material was 270.51 mg/g. The adsorption capacity was high in both acidic and alkaline environments, especially the alkaline environment. [ABSTRACT FROM AUTHOR]

As a new type of fluorescent carbon nanomaterials, carbon quantum dots have been widely concerned in recent years because of their good biocompatibility, low cytotoxicity and easy surface functionalization. In this paper, nitrogen-doped carbon quantum dots (N-CQDs) were prepared by one-step hydrothermal method with citric acid as the carbon source and urea as a nitrogen source. The fluorescence spectrophotometer, Fourier infrared spectrometer, X-ray diffractometer, and transmission electron microscope were utilized to discover the luminescence properties, structural characteristics, morphology and size of the synthesized N-CQDs. The results showed that the best reaction conditions for preparing N-CQDs were as follows: the hydrothermal process parameters were 240 °C for 10 h, and the concentration of nitrogen doping was 0.6 wt%. Under these conditions, the prepared N-CQDs with bright blue fluorescence solution was uniform and stable. And the results showed the structural characteristics were weak crystalline graphite carbon, and the shape characteristics were nearly spherical quantum dot with about 5–10 nm diameters. [ABSTRACT FROM AUTHOR]

In this study, a novel hydroxyapatite (HA)/polyurethane (PU) composite porous 3D scaffold was developed by in situ polymerization. Aliphatic hexamethylene diisocyanate (HDI) as a nontoxic and safe agent was adopted to produce the rigid segment in PU polymerization. HA powder was compounded in a PU polymer matrix during the polymeric process. The macrostructure and morphology as well as mechanical strength of the scaffolds were characterized by FTIR, XRD and SEM. The results show that the HDI can react mildly with hydroxyl (–OH) groups of polytetramethylene ether glycol and a mild foaming action caused by the release of CO2 gas occurred simultaneously in the reactive process, thus producing a uniform porous structure of HA/PU scaffold. The HA/PU composite scaffold with a high HA content of about 30 wt% has a porosity of more than 60% and a pore size from 100 to 800 μm. After immersed in simulated body fluid, the scaffolds were investigated by weight loss experiments and FTIR. The results show that polymerized component of HA/PU scaffolds degraded gradually in vitro, while HA component presented a classic trend of dissolution then deposition procedure. Three hydrolysis processes may happen in the PU degradation. The HA/PU scaffolds should be a promising material for bone tissue regeneration in clinic. [ABSTRACT FROM AUTHOR]

In the study, a new kind of tetrad cathode lithium-ion battery material (LiNi0.6Co0.2-xMn0.2VxO2 (x = 0, 0.06, 0.08, 0.10)) was synthesized and then characterized by XRD, XPS, SEM, EDS, electrochemical measurements, CV, and EIS. The homogenous distribution of vanadium element on the materials was verified and the layer crystal structure was not changed when x = 0.08. XPS results indicated that suitable vanadium substitution reduced cation mixing on the surface due to the lower content of Ni2+. Electrochemical measurements confirmed that LiNi0.6Co0.12Mn0.2V0.08O2 had the highest initial coulombic efficiency (80 % at 0.05 C), rate capacity (129.4 mAh/g at 5 C), and cycling performance (92.6% at 1 C) at the cutoff voltage of 4.6 V, which were much better than those of LiNi0.6Co0.2Mn0.2O2. LiNi0.6Co0.12Mn0.2V0.08O2 showed good dynamic properties in CV and EIS tests. The results of XRD and SEM for cycled electrodes showed that the introduction of vanadium could significantly relieve structural damages of LiNi0.6Co0.2Mn0.2O2 during charge/discharge processes. This study indicated that controlled vanadium introduction could effectively improve the electrochemical performance of LiNi0.6Co0.2Mn0.2O2 for developing the high-voltage cathodes for high-energy lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Luminescent perovskite photocatalysts activated by Pr3+ were prepared by combustion. The structural phase, morphology, and chemical composition of the as-prepared photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) analysis, and ultraviolet–visible (UV–vis) diffuse reflectance spectroscopy. The photocatalytic activities of the synthesized samples were investigated on the basis of the degradation of methylene blue (MB) under UV light irradiation. CaTiO3:Pr3+ was obtained in high purity and good crystallinity with a perovskite structure. The degradation of the photocatalyst was fitted with pseudo-first-order kinetics according to the Langmuir–Hinshelwood model. Compared to CaTiO3:Pr3+, Ca1–xTiO3:Pr3+ (x = 0–0.3) multifunctional materials exhibit higher luminescence intensity and photocatalytic activity toward the degradation of MB. Ca0.8TiO3:0.1%Pr3+ exhibited the best performance. [ABSTRACT FROM AUTHOR]

Abstract Zinc citrate is an organic salt complex prepared with organic carboxylate and inorganic cation. In the study, a series of C12H14O16Zn3: Eu3+ phosphors were synthesized through a facile hydrothermal method and then the as-prepared phosphors were characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM), and photoluminescence (PL) spectrometer. The morphology of C 12 H 14 O 16 Zn 3 : Eu3+ phosphors was a flake with the size of 1～10 μm × 0.5～5 μm and the length-width ratio of 0.2–20. The strongest emission peak of C 12 H 14 O 16 Zn 3 : Eu3+ at 621 nm was ascribed to 5D o →7F 2 transition of Eu3+ and the peaks centered at 590, 653 and 702 nm respectively corresponded to 5D o →7F 1 , 7F 3 , and 7F 4 transitions. C 12 H 14 O 16 Zn 3 : Eu3+ gave the red light emission, as indicated by color coordinate analysis. The photoluminescence intensity of the phosphors prepared under the Eu3+ concentration of 7% was the highest. As a new kind of phosphor, C 12 H 14 O 16 Zn 3 : xEu particles may be applied in biological fluorescent tags and luminescent materials. Highlights • C 12 H 14 O 16 Zn 3 :Eu3+ phosphors prepared with zinc citrate as matrix, which owns high structural stability and thermal stability. • Eu3+ doped C 12 H 14 O 16 Zn 3 phosphors can be synthesized through a facile hydrothermal method. • The photoluminescence intensity of the C 12 H 14 O 16 Zn 3 :Eu3+ phosphors was the highest under the Eu3+ concentration of 7%. • C 12 H 14 O 16 Zn 3 :Eu3+ phosphors gave red light emission, may be applied in biological fluorescent tags and luminescent materials. [ABSTRACT FROM AUTHOR]

Praseodymium-doped perovskite Functional mineral material was synthesized via the combustion method. The crystal structure and morphologies were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM). The photocatalytic performance was studied by the degradation experiment of inferior methyl blue. The results indicate that CaTiO3 has good photocatalytic degradation performance for the inferior methyl blue under UV-irradiation condition and the Pr3+-doping significantly improved the photocatalytic efficiency. The degradation rate of MB decreased with the increasing initial concentration. Furthermore, The degradation rate of MB increased first and then decreased with the increasing concentration of catalyzer. [ABSTRACT FROM AUTHOR]

• This study proposes a high c (LiCl)-based hydrothermal cultivation method. • Crystal structure was regenerated and fragments of gibbsite were reassembled. • Adsorption capacity increased to 5.85 mg/g after repair. This study proposes a high c (LiCl)-based hydrothermal cultivation method for the structural damage regeneration of Li/Al-LDHs. The crystal structure was regenerated and small fragments of gibbsite were reassembled into rose petal-shaped Li/Al-LDHs. The analysis of Li+ adsorption kinetics and isotherm reveals that while the structural damage of Li/Al-LDHs has no impact on the mode or rate of adsorption, it does have a substantial effect on the adsorption capacity. This study provides a reuse method of Li/Al-LDHs. [ABSTRACT FROM AUTHOR]

A series of Cd 2 V 2 O 7 :Eu 3+ , Li + red phosphors was prepared by a solid-state reaction method. A pure Cd 2 V 2 O 7 phase with monoclinic structure was obtained by heating to a temperature range of 600–850 °C. The effects of Eu 3+ doping and Li + co-doping concentrations on the luminescence properties of Cd 2 V 2 O 7 :Eu 3+ , Li + samples were investigated. Under excitation at 375 nm, the as-prepared Cd 2 V 2 O 7 :Eu 3+ phosphors exhibit a red emission peak at 618 nm due to the 5 D 0 → 7 F 2 electronic transition of Eu 3+ . The luminescence properties of Cd 2 V 2 O 7 :Eu 3+ , Li + samples are improved significantly by the addition of Li + as charge compensator compared to the Cd 2 V 2 O 7 :Eu 3+ phosphor. The results indicate that Cd 2 V 2 O 7 :Eu 3+ , Li + phosphor could be a promising red phosphor in near ultraviolet-excited white light-emitting diodes for warm white light. [ABSTRACT FROM AUTHOR]

A series of Eu 3+ -doped C 12 H 18 Ca 3 O 18 phosphors were synthesized through a facile hydrothermal method and the properties of as-prepared phosphors were explored by X-ray diffractometer (XRD), scanning electron microscope (SEM), and photoluminescence (PL) spectrometer. The exploration results indicated that the C 12 H 18 Ca 3 O 18: Eu 3+ had been successfully synthesized. The morphology of C 12 H 18 Ca 3 O 18: Eu 3+ was a strip with the size of 100–4000 nm × 50–400 nm × 50–200 nm and the ratio of length to width of 2–80. The strongest emission peak of C 12 H 18 Ca 3 O 18: Eu 3+ around 620 nm was ascribed to 5 D o → 7 F 2 transition of Eu 3+ , and the peaks centered at 590, 653 and 694 nm respectively corresponded to 5 D o → 7 F 1 , 7 F 3 , and 7 F 4 transitions. C 12 H 18 Ca 3 O 18: Eu 3+ gave the red light emission, as indicated by color coordinate analysis. The photoluminescence intensity of the phosphors prepared under the Eu 3+ concentration of 6% was the highest. The crystal structure of C 12 H 18 Ca 3 O 18: Eu 3+ was changed after europium ions occupied the lattice position of calcium ions. Europium ion could displace calcium arbitrarily. As a new kind of matrix, calcium citrate possesses the properties of both organic and inorganic compounds and the luminescent C 12 H 18 Ca 3 O 18 : x Eu 3+ particles may be applied in biological fluorescent tags and luminescent materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • In situ construction of multiphase through controlled hydrothermal and oxidation. • High efficiency by increasing Fe ions adsorbed and constructing p-n junction. • Material with efficient synergistic degradation of Cr(VI) and MO. In this study, the magnetic composite particles composed of marcasite, pyrite, and magnetite were prepared with the hydrothermal process and oxidation. The coexistence of marcasite and pyrite was achieved by controlling the sulfur content in the hydrothermal process, and surface magnetite was realized by controllable oxidation. The typical composite particles presented the regular spherical size of 5 to 7 μm and could degrade 41.2 % MO as well as reduce 98 % Cr(VI). In the mixed solution of MO/Cr(VI), the synergistic degradation rate of MO increased from 41.2 % to 70.5 % and the reduction rate of Cr(VI) could still reach 98 %. Multiphase recombination could increase Fe adsorbed on the material surface and construct the p-n junction. In addition, surface magnetite endowed the material with magnetic recyclability. In situ multiphase recombination turned cheap FeS 2 into a valuable treatment agent for mixed pollutants. [ABSTRACT FROM AUTHOR]

Due to the lack of rare earth resources, the recovery of rare earth ions from industrial wastewater has been widely concerned. In this work, NaY molecular sieve was synthesized at 50–90 °C for 3–10 h without template and guide agent by low-temperature ultrasonic gelling method, and it was examined as the adsorbent to recover and enrich La3+ and Eu3+ in synthetic rare earth liquids. The properties of the synthesized NaY crystallization at 90 °C for 5 h were determined as follows: relative crystallinity of 99.49%, average particle size of 300 nm, specific surface area of 873.66 m2/g, and average aperture of 0.5617 nm. When the adsorption temperature was 25 °C, the pH was about 7, the initial concentrations of La3+ and Eu3+ were 227.00 mg/L and 195.30 mg/L, respectively, the amount of NaY was 0.01 g, and the volume of the rare earth simulant was 10 ml, the unit adsorption capacity and adsorption efficiency of La3+ were respectively 174.12 mg/g and 75.30%, and the unit adsorption capacity and adsorption efficiency of Eu3+ were 147.47 mg/g and 75.51%, respectively. After four cycles, the unit adsorption efficiency of La3+ and Eu3+ were still respectively 93.20 mg/g and 91.00 mg/g. The adsorption process showed a closer agreement with Langmuir isotherm and quasi-second-order kinetics model. The results indicate that this NaY molecular sieve is a promising adsorbent for rare earth recycling and enrichment from wastewater. [Display omitted] • NaY molecular sieve for rare earth adsorption is rapidly synthesized. • The synthesized NaY has good adsorption and desorption effect on La3+ and Eu3+. • NaY based on its ion exchange effect shows excellent cycle performance. [ABSTRACT FROM AUTHOR]

A series of single-phase color-turning CaZrO 3 : Ln (Ln = Tb3+, Eu3+, Tb3+/Eu3+) phosphors was synthesized through citric acid-fueled combustion method. The as-prepared samples had the perovskite structure with Pnma space group and elements uniformly distributed in nanosized particles. CaZrO 3 : Eu3+ phosphor produced red luminescence due to the 5D 0 →7F 2 transition at 619 nm CaZrO 3 : Tb3+ phosphor produced green and blue luminescence due to the 5D 4 →7F 6, 5 transition at 487 nm and 548 nm. Under UV irradiation at 254 nm, the CaZrO 3 : Ln (Ln = Tb3+, Eu3+, Tb3+/Eu3+) phosphors achieved tunable full-color emission in a wide range from blue to green, warm white, and red. The corresponding CIE coordinates were (0.2546, 0.2413), (0.3196, 0.5085), (0.3603, 0.3896) and (0.6089, 0.3844). The energy transfer from ZrO 3 2− to Tb3+ and then to Eu3+ was determined by the dipole-dipole mechanism in CaZrO 3 : 0.03 Tb3+, xEu3+ phosphors. The excellent temperature stability of CaZrO 3 : 0.03 Tb3+, 0.01Eu3+ phosphor (ΔE = 0.2659 eV) indicates that CaZrO 3 : Ln (Ln = Tb3+, Eu3+, Tb3+/Eu3+) phosphors have broad application prospects in W-LED devices. • A lower temperature fast method (900 °C) was used to synthesize RE-doped CaZrO 3 phosphors. • Full-color-emitting from blue to green, warm white and red single-phase CaZrO 3 : Ln phosphors. • Recognition of the energy transfer mechanism between ZrO 3 2−, Eu3+ and Tb3+. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two dimensional B 2 S and B 2 S 3 with lithiophilic S-element and sulfiphilic B-element were employed as novel additive for Li-S batteries. • B 2 S and B 2 S 3 exhibit remarkable catalytic activity toward the liquid-solid and solid-solid transition of LiPSs. • Soluble LiPSs can be effectively anchored by the B 2 S and B 2 S 3 additive. • High mass transfer of Li-ions on B 2 S and B 2 S 3 expedites the nucleation and decomposition of LiPSs. The sluggish transformation kinetics of lithium polysulfides (LiPSs) and the notorious shuttle effect induced by the emergence of highly soluble LiPSs have become the main obstacles preventing the application of lithium-sulfur batteries. The development of bifunctional catalysts capable of accelerating the LiPSs redox kinetics and anchoring these soluble LiPSs is highly desirable for achieving improved cycling performance and Coulombic efficiency. Herein, a two-dimensional B 2 S/B 2 S 3 catalyst with atomically dispersed boron and sulfur sites was investigated as a potential additive to boost the anchoring of soluble LiPSs and the subsequent LiPSs transformation reaction. Based on first-principles calculations, we demonstrated that the adsorption strengths of soluble LiPSs on B 2 S/B 2 S 3 monolayers are neither strong nor weak. This effectively inhibits the dissolution of LiPSs while retaining their structural integrity. Importantly, B 2 S/B 2 S 3 exhibits remarkable catalytic activity toward the liquid-solid (Li 2 S 4 to Li 2 S 2) and solid-solid (Li 2 S 2 to Li 2 S) reactions in the discharging process as well as the decomposition of Li 2 S in the charging process. This is crucial for achieving improved rate performance. Moreover, a high Li-ion mass transfer efficiency on B 2 S and B 2 S 3 was achieved with E bar values of 0.43 and 0.41 eV, which is beneficial for reducing diffusion-dependent polarization issues. Our results provide an alternative route for developing advanced sulfur cathode catalysts with a suppressed shuttle effect and desirable rate performance. [ABSTRACT FROM AUTHOR]

In order to solve the pollution of heavy metals and organic antibiotic in the water environment, a novel CuBi 2 O 4 /calcined ZnAlBi layered double hydroxides (CBO/CLDHs) composite was constructed and prepared via an ultrasonic-assisted calcination method for the adsorption and photocatalysis synergetic effect. Through varying the composition ratio, pH value, initial pollutant concentration and other pollutant interference, the simultaneous removal ability including adsorption and photocatalysis of as-prepared CBO/CLDHs composites for Cr(VI) and tetracycline pollutants was discussed. In particular, the CBO/CLDHs-1/15 composite showed that the removal efficiencies of Cr(VI) (40 mg/L) and tetracycline (40 mg/L) were both above 95%. Meanwhile, the XPS results confirmed that the toxic Cr(VI) was gradually reduced to non-toxic Cr(III) under visible light irradiation. The enhanced adsorption and photocatalytic activity was mainly attributed to the uniform distribution of calcined ZnAlBi layered double hydroxides nanosheets on the CuBi 2 O 4 microrods and the formation of heterojunctions. Moreover, cycle performance results revealed that the CBO/CLDHs-1/15 composite maintained high removal activity and stable structure after 4 photocatalytic cycles, and even showed a good adaptability while applied to the actual water in production and living environments. These results exhibited that the as-prepared CBO/CLDHs-1/15 composite has excellent adsorption and photocatalytic ability for the simultaneous removal of Cr(VI) and tetracycline, with a great potential application in practical waste water treatment field. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Co2+-doped ZnO nanoarrays was first grown on substrate and used as photocatalyst. • Co2+ was doped to improve the photocatalytic activity under visible-light induction. • Co2+-doped ZnO efficiently remove organic pollutants for environmental protection. In order to remove the organic pollution from water environment, Co2+-doped ZnO nanoarray photocatalyst was prepared through a hydrothermal process. The influences of Co2+ doping amount and hydrothermal temperature on the nanostructure and photocatalytic performance of Co2+-doped ZnO nanoarray were discussed in detail. The standard ZnO structure and nanoarray morphology of Co2+-doped ZnO samples were achieved and the absorption of visible light was also realized through Co2+ doping. The 2% Co2+-doped ZnO nanoarray prepared at 95 °C exhibited excellent photocatalytic activity and could degrade 96% of methylene blue solution within 120 min under visible light. Furthermore, the as-prepared 2% Co2+-doped ZnO nanoarray still maintained 91% for removal rate after 3 cycles of photocatalytic degradation, showed good photocatalytic activity and recyclability. All results indicate that ZnO nanoarray with Co2+ doping has a potential application in visible light photocatalysis for environmental protection and pollution control. [ABSTRACT FROM AUTHOR]

Degradable scaffolds with high porosity, certain mechanical and shape memory properties and biocompatibility are ideal materials in the field of bone tissue engineering for minimally invasive surgical implantation methods. In this study, we prepared porous scaffolds using hydrophilic polyethylene glycol and degradable polycaprolactone as raw materials and calcium citrate/amorphous calcium phosphate as hybrid particles, via sequential gas foaming, salt leaching and freeze drying methods. The fabricated bone scaffold exhibited adjustable mechanical properties and pore structure, with high shape fixation (>94.5%) and shape recovery (>87%) in thermal cycling and excellent shape memory properties under simulated body fluid immersion near body temperature. Moreover, in cell proliferation and live/dead cell activity assay experiments, the scaffolds promoted the proliferation of mesenchymal stem cells (MSCs). Immunofluorescence staining assay experiments further showed that the scaffolds had strong expressions of human type Ⅰ collagen (Col I) and alkaline phosphatase (ALP) in bone matrix. The material is expected to be a potential alternative material for bone tissue engineering. Smart foams recovered from squeezed shape to porous shape under thermal condition with well distribution of CA particles. [Display omitted] [ABSTRACT FROM AUTHOR]

A convenient and effective method was developed to fabricate zirconium-based calcium sulfate whiskers (Zr-CSWs), an environmentally friendly adsorption material designed to clean excessive fluoride from wastewater. Zr-CSWs, which potentially provide high adsorption activity toward fluoride in wastewater, overcome an aggregation problem typical of Zr-based species that may block the pore structure of the supporting material and degenerate its treatment performance. The results indicate that Zr-CSWs show excellent equilibrium adsorption capacity compared to other Zr-based materials in practical water solutions with pH values of 6–7. The adsorption of fluoride on Zr-CSWs was further evaluated in accordance with the Langmuir equation and the pseudosecond-order model. Coexisting anions had a minor effect on the removal of fluoride, and a strong alkali solution regenerated the used adsorbent. Density functional theory (DFT) calculations were performed to determine the mechanism of fluoride removal. The calculations demonstrated that the removal of fluoride by Zr-CSWs was mainly achieved by ion exchange between fluoride ions and OH- on the surface of the adsorbent, where a protonation process created low-coordination Zr atoms. [Display omitted] • Zirconium decorated calcium sulfate whisker (Zr-CSW) was prepared in a simple and low-cost way. • Zr-CSW has high capacity and good selectivity for the removal of fluoride in water. • The adsorption follows Langmuir model and pseudosecond-order dynamic equation. • The mechanism for fluoride removal has been revealed by density of functional theory (DFT). [ABSTRACT FROM AUTHOR]

• Glass with a high vanadium content improved the migration efficiency of Li+. • Adding Fe 2 O 3 stabilized the structure and increased the contents of V3+ and V4+. • The cathode has the outstanding specific capacity and high-current response. Among new lithium-ion battery cathode materials, amorphous materials show unique advantages and vanadium-based materials are potential electrode materials. In our study, the vanadium-based Li 2 O-V 2 O 5 -B 2 O 3 glassy state electrode materials with high vanadium contents were prepared in air by the melt-quenching method. The structures and electrochemical performances of glass materials were investigated by various characterization methods. The Li 2 O-V 2 O 5 -B 2 O glass were mainly connected with VO 4 and BO 3 structural units to form a disordered network structure. The first discharge capacity of 20Li 2 O-60 V 2 O 5 -20B 2 O 3 glass cathode material reached 168.6 mAh/g at a current density of 100 mA/g. The conversion of V3+/V4+ and V4+/V5+ mainly occurred in the charge and discharge cycles. When 10% of B 2 O 3 was replaced by Fe 2 O 3 , the compactness and stability of the material were improved. Furthermore, with the addition of Fe 2 O 3 , the concentrations of low-valence V4+, V3+ and Fe2+ ions increased, thus contributing to the electrochemical performance. The specific capacity of 20Li 2 O-60V 2 O 5 -10B 2 O 3 -10Fe 2 O 3 cathode material increased significantly and the first discharge capacity was as high as 306.2 mA h/g at a current density of 100 mA/g. However, the specific capacity respectively decreased to 239 mA h/g in the second cycle and 120.3 mA h/g after 100 cycles. The study on vanadium-based glass cathode materials provided a new idea for the investigation of novel cathode materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pristine MoBOH system exhibits weak affinity to typical VOCs. • Decoration of Ca can enhance the adsorption performance towards VOCs. • Doped Ca atoms act as a medium to link MoBOH substrate with VOCs. • Ca-decorated MoBOH might be a potential candidate for VOC removal. Volatile organic compounds (VOCs) have caused severe problems in the atmospheric environment and human health, necessitating the development of effective adsorbents for their removal at room temperature. In this study, we explored the feasibility of pristine and alkaline-earth metal (Ca, Mg) and Al decorated MoBOH as an effective adsorbent for four typical VOCs (CH 2 O, C 6 H 6 , C 3 H 6 O, and C 2 HCl 3) based on density functional theory. The results show that MoBOH exhibits desirable structural stability enduring repeat lattice expansion/contraction upon the storage/release of gas molecules. Nevertheless, MoBOH exhibits weak adsorption towards VOCs, where the hosted VOC molecules would be desorbed as the temperature increases to room temperature. Ca, Mg, and Al were used to decorate the MoBOH to improve its adsorption performance. MoBOH exhibited an unexpected high affinity towards Ca in comparison to Mg and Al. Thermodynamic analysis shows that Ca-decorated MoBOH effectively adsorbed the VOCs at room temperature and normal pressure with a moderate desorption temperature (from 405 K to 487 K). The mechanisms were elucidated by analyzing the partial density of states, charge transfer, and electron density difference. The results show that the Ca-decorated MoBOH monolayer is a potential adsorbent for VOC removal under ambient conditions. [ABSTRACT FROM AUTHOR]

• The Zn-CQDs are synthesized based on zinc citrate chelate as the precursor is proposed. • Zn-CQDs obtain a high photoluminescence intensity, which is eightfold compared to undoped CQDs. • The fluorescence quantum yield of Zn-CQDs is 48%, higher than undoped CQDs, 37%. • With the increase in Zn2+ concentration, the PL spectrum of Zn-CQDs show a red shift phenomenon. • Zn-CQDs are ideal material for biomedical, bioimaging, optoelectronics, and catalysis. The Zn2+ doped Carbon Quantum Dots (Zn-CQDs) were synthesized with zinc citrate chelate as the precursor by a hydrothermal method. The evaluation results indicated that Zn2+ was successfully embedded in CQDs. Most of Zn2+ ions were combined with carboxyl groups on the surface of carbon dots to form Zn-O bonds and some Zn2+ ions were embedded in the interstice points of CQDs. The remaining Zn2+ were reduced to zinc atoms and adsorbed on the surface of CQDs. With the increase in Zn2+ concentration, the size of synthesized Zn-CQDs increased. When zinc ion concentration increased to 9%, the average size of Zn-CQDs grew up to 8 nm, but the size of undoped CQDs was just 1.5 nm. When Zn2+ concentration increased from 1% to 9%, the fluorescence intensity increased, while reaching above 9%, the fluorescence intensity showed a downward trend. When Zn2+ concentration was 7%, the fluorescence quantum yield of Zn-CQDs increased to 48%, but the fluorescence quantum yield of undoped CQDs was only 37%. With the increase in Zn2+ concentration, the PL spectrum of Zn-CQDs showed a red shift phenomenon. In addition, Zn-CQDs showed superior fluorescent sensing capability to Fe3+ and Hg2+, presenting greater fluorescence quenching effect on Fe3+ and Hg2+ than CA-CQDs. Therefore, Zn-CQDs demonstrated excellent fluorescence properties and can be applied in fluorescent sensor, biological imaging, optoelectronics, and catalysis fields. [ABSTRACT FROM AUTHOR]

In this study, a novel polyurethane porous 3D scaffold based on polyethylene glycol (PEG) and polytetrahydrofuran glycol (PTMG) was developed by in situ polymerization and freeze drying. Aliphatic hexamethylene diisocyanate (HDI) as a nontoxic and safe agent was adopted to produce the rigid segment in polyurethane polymerization. The chemical structure, macrostructure, and morphology—as well as mechanical strength of the scaffolds—were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), and tensile tests. The results show that the HDI can react mildly with hydroxyl (–OH) groups of PEG and PTMG, while gas foaming action caused by the release of CO2 occurred simultaneously in the reactive process, resulting in a uniform porous structure of PU scaffold. Moreover, the scaffolds were soaked in water and freeze dried to obtain higher porosity and more interconnective microstructures. The scaffolds have a porosity of over 70% and pore size from 100 to 800 μm. The mechanical properties increased with increasing PEG content, while the hydrophilicity increased as well. After immersion in simulated body fluid (SBF), the scaffolds presented a stable surface structure. The gas foaming/freezing drying process is an excellent method to prepare skin tissue engineering scaffold from PTMG/PEG materials with high porosity and good inter connectivity. [ABSTRACT FROM AUTHOR]

In order to avoid the shortcoming of the luminescence singleness of traditional carbon quantum dots (CQDs), the free regulation of luminous color of CQDs were achieved by doping lanthanide ions in the study. Firstly, Eu3+-doped carbon quantum dots (Eu-CQDs) were synthesized with citric acid-chelated europium ions as the precursor by a hydrothermal method. Doped europium ions existed in the Eu(III) state in Eu-CQDs and the prepared Eu-CQDs showed two parts of the photoluminescence (PL) spectrum, which originated from the blue emission of CQDs and the characteristic photoluminescence of Eu3+ ions, respectively. With an increase in the concentration of Eu3+, the intensity of Eu3+ characteristic emission showed an enhanced trend, but the intensity of the characteristic peaks of CQDs decreased. The CIE coordinate confirmed the continuous regulation of the luminous color of CQDs from blue to red. When the concentration of Eu3+ ions was 6%, the ratio of PL intensity between Eu3+ ions and CQDs was higher, thus generating purple-red light emission. In addition, the dual fluorescent characteristics of Eu-CQDs showed quite different responses to different environment pH values. When pH = 6, the CCT value of Eu(6%)-CQDs was 2156 K, indicating a good red light performance. The white light emission of CQDs could be realized by co-doping 5 mol% Eu3+ and 2 mol% Tb3+ in CQDs and adjusting the environmental pH = 7. The CCT value of doped CQDs was 5115 K, indicating a good neutral white light performance. • The Ln-CQDs were synthesized with citric acid chelated lanthanide ions as the precursor. • The continuous regulating of the luminous color of the CQDs from blue to red could be achieved. • The white light emission of CQDs could be realized by co-doping Eu3+ and Tb3+. [ABSTRACT FROM AUTHOR]

A novel white emitting phosphate-based phosphor Ca 3- x Li x (PO 4) 2- x (SO 4) x :Dy3+, Sm3+ with high emission intensity and lower correlated color temperature were successfully synthesized via the sol-gel method. The structures of these prepared phosphors matched well with standard Ca 3 (PO 4) 2. The Dy3+-doped Ca 3- x Li x (PO 4) 2- x (SO 4) x phosphors showed white luminescence via the combination of blue (487 nm) and yellow (578 nm) emissions, which were attributed to the 4F 9/2 → 6H 15/2 and 4F 9/2 → 6H 13/2 electron transitions of Dy3+, respectively. The synthesized phosphor exhibited a significant enhancement in luminescence intensity at the optimum value of x = 0.15. With the incorporation of Sm3+, a warm white emission with lower correlated color temperature (4281 K) was achieved in Dy3+/Sm3+ co-doped samples. The obtained external quantum efficiency reached 21.7% in the optimized phosphor. The improved performance was strongly associated with red emission supplemented by Sm3+, and it demonstrated the existence of efficient energy transfer between the Dy3+ and Sm3+ ions (4F 9/2 → 4G 7/2 and 4F 9/2 → 4G 5/2). Overall, the investigation carried out by us has revealed that the luminescence properties of Ca 3 (PO 4) 2 phosphor can be significantly improved through Li+/S6+ partial substitution and Dy3+/Sm3+ co-doping. Image 1 • A novel Li+/S6+ co-substituted Ca 3 (PO 4) 2 :Dy3+ white-emitting phosphor was prepared. • Ca2+/P5+ couples were partially substituted with Li+/S6+ for luminescence enhancement. • A white light could be realized with a blue emission and yellow emission of Ca 3- x Li x (PO 4) 2- x (SO 4) x :Dy3+. • Warm white emission with low CCT can be achieved for Ca 2 · 85 Li 0 · 15 (PO 4) 1 · 85 (SO 4) 0.15 :Dy3+ phosphor by Sm3+ ions co-doping. [ABSTRACT FROM AUTHOR]

A series of Ca(Ti 1− x Zr x)O 3 :Dy3+ phosphors were fabricated using a combustion method. The lattice structure, morphological features, and luminescence performances of the specimens were obtained. Rietveld refinement of the XRD patterns confirmed the crystal distortion of CaTiO 3 after Zr4+codoping and the positional occupation of Zr4+ in the CaTiO 3 crystal lattice. The photoluminescence spectroscopy results indicated that the fluorescence emission intensity of CaTiO 3 :Dy3+ was substantially enhanced by Zr4+ codoping and that the optimum doping concentration of Zr4+ was 40% mol. The quantum yield of the Ca(Ti 0·6 Zr 0.4)O 3 :Dy3+ phosphor was measured to be 9.9%, and its fluorescence lifetime decreased with the increasing concentration of Zr4+ doping. Furthermore, the lowest color temperature was observed for Ca(Ti 0·6 Zr 0.4)O 3 :Dy3+ among the investigated phosphors and its color coordinate was the closest to the standard white-light color coordinate. These results suggest that the Ca(Ti 0·6 Zr 0.4)O 3 :Dy3+ phosphor excited by near-ultraviolet light is a potential material for application in white light-emitting diodes. • The lattice parameters changes after incorporation of Zr4+ into CaTiO 3 :Dy3+. • The XRD structural refinement certificated the rationalization of Zr4+ substitute Ti4+ in CaTiO 3 :Dy3+ structure. • The fluorescence properties enhanced after Zr4+ doping. [ABSTRACT FROM AUTHOR]