Preparation of Microporous Polypropylene/Titanium Dioxide Composite Membranes with Enhanced Electrolyte Uptake Capability via Melt Extruding and Stretching

In this work, a blending strategy based on compounding the hydrophilic titanium dioxide (TiO2) particles with the host polypropylene (PP) pellets, followed by the common membrane manufacture process of melt extruding/annealing/stretching, was used to improve the polarity and thus electrolyte uptake capability of the PP-based microporous membranes. The influence of the TiO2 particles on the crystallinity and crystalline orientation of the PP matrix was studied using differential scanning calorimetry (DSC), X-ray diffraction (XRD), and infrared dichroic methods. The results showed that the TiO2 incorporation has little influence on the oriented lamellar structure of the PP-based composite films. Investigations of the deformation behavior indicated that both the lamellar separation and interfacial debonding occurred when the PP/TiO2 composite films were subjected to uniaxial tensile stress. The scanning electron microscopy (SEM) observations verified that two forms of micropores were generated in the stretched PP/TiO2 composite membranes. Compared to the virgin PP membrane, the PP/TiO2 composite membranes especially at high TiO2 loadings showed significant improvements in terms of water vapor permeability, polarity, and electrolyte uptake capability. The electrolyte uptake of the PP/TiO2 composite membrane with 40 wt % TiO2 was 104%, which had almost doubled compared with that of the virgin PP membrane

Preparation of Microporous Polypropylene/Titanium Dioxide Composite Membranes with Enhanced Electrolyte Uptake Capability via Melt Extruding and Stretching

In this work, a blending strategy based on compounding the hydrophilic titanium dioxide (TiO2) particles with the host polypropylene (PP) pellets, followed by the common membrane manufacture process of melt extruding/annealing/stretching, was used to improve the polarity and thus electrolyte uptake capability of the PP-based microporous membranes. The influence of the TiO2 particles on the crystallinity and crystalline orientation of the PP matrix was studied using differential scanning calorimetry (DSC), X-ray diffraction (XRD), and infrared dichroic methods. The results showed that the TiO2 incorporation has little influence on the oriented lamellar structure of the PP-based composite films. Investigations of the deformation behavior indicated that both the lamellar separation and interfacial debonding occurred when the PP/TiO2 composite films were subjected to uniaxial tensile stress. The scanning electron microscopy (SEM) observations verified that two forms of micropores were generated in the stretched PP/TiO2 composite membranes. Compared to the virgin PP membrane, the PP/TiO2 composite membranes especially at high TiO2 loadings showed significant improvements in terms of water vapor permeability, polarity, and electrolyte uptake capability. The electrolyte uptake of the PP/TiO2 composite membrane with 40 wt % TiO2 was 104%, which had almost doubled compared with that of the virgin PP membrane

HKUST-1/ZIF-67 Nanocomposites as Heterogeneous Cu–Co-Bimetallic Fenton-like Catalysts for Efficient Removal of Methylene Blue

Fenton-like reactions with Fe-based metal–organic framework (MOF) catalysts have been extensively explored in the field of environmental remediation. However, easy precipitation of Fe2+/Fe3+ and the production of sludge under basic conditions caused catalyst loss and greatly limited their large-scale application in industry. The development of an Fe-free Fenton-like reaction is of extreme importance and remains in its infant stage. Herein, a series of Fe-free dual MOF nanoparticles (HKUST-1/ZIF-67-X) were fabricated by in situ coating of ZIF-67 on HKUST-1 and were systematically analyzed by various characterization techniques, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), and N2 adsorption–desorption isotherms. Subsequently, these materials were applied in catalyzing methylene blue (MB) degradation. The effects of several operation parameters, i.e., pH, H2O2 dosage, catalyst dosage, and reaction temperature, on MB degradation were investigated. It was unveiled that HKUST-1/ZIF-67-7% exhibited an outstanding catalytic activity without the production of any sludge, which could reach as high as 93.29% MB degradation efficiency within 40 min. This was attributed to the unique core–satellite histoarchitecture of HKUST-1/ZIF-67-7% and the synergistic effect between HKUST-1 and ZIF-67. The HKUST-1/ZIF-67-7% composite still achieved up to 80.17% MB degradation efficiency at the fifth catalysis cycle. Importantly, HKUST-1/ZIF-67-7% exhibited significant catalytic efficiency under a wide pH range (4.2–10.1) and top catalytic efficiency at the near neutral pH value. The low cost, environment benignancy, satisfactory degradation efficiency, wide pH application range, and excellent reusability emphasize its great application potential in Fenton-like degradation of pollutants. This contribution could provide a paradigm investigation for designing non-iron-based MOF catalysts to solve the increasingly pressing pollution issues

An efficient bifunctional Ni-Nb2O5 nanocatalysts for the hydrodeoxygenation of anisole

The Ni-Nb2O5 nanocatalysts have been prepared by the sol-gel method, and the catalytic hydrodeoxygenation (HDO) performance of anisole as model compound is studied. The results show that Nb exists as amorphous Nb2O5 species, which can promote Ni dispersion. The addition of Nb2O5 increases the acidity of the catalyst. However, when the content of niobium is high, there is an inactive Nb-Ni-O mixed phase. The size and morphology of Ni grains in catalysts are different due to the difference of Nb/Ni molar ratio. The Ni0.9Nb0.1 sample has the largest surface area of 170.8 m2·g-1 among the catalysts prepared in different Nb/Ni molar ratios, which is mainly composed of spherical nanoparticles and crack pores. The HDO of anisole follows the reaction route of the hydrogenation HYD route. The Ni0.9Nb0.1 catalyst displayed a higher HDO performance for anisole than Ni catalyst. The selectivity to cyclohexane over the Ni0.9Nb0.1 sample is about 10 times that of Ni catalyst at 220 ℃ and 3 MPa H2. The selectivity of cyclohexane is increased with the increase of reaction temperature. The anisole is almost completely transformed into cyclohexane at 240℃, 3 MPa H2 and 4 h

Breaking Low-Strain and Deep-Potassiation Trade-Off in Alloy Anodes via Bonding Modulation for High-Performance K‑Ion Batteries

Alloy anode materials have garnered unprecedented attention for potassium storage due to their high theoretical capacity. However, the substantial structural strain associated with deep potassiation results in serious electrode fragmentation and inadequate K-alloying reactions. Effectively reconciling the trade-off between low-strain and deep-potassiation in alloy anodes poses a considerable challenge due to the larger size of K-ions compared to Li/Na-ions. In this study, we propose a chemical bonding modulation strategy through single-atom modification to address the volume expansion of alloy anodes during potassiation. Using black phosphorus (BP) as a representative and generalizing to other alloy anodes, we established a robust P–S covalent bonding network via sulfur doping. This network exhibits sustained stability across discharge–charge cycles, elevating the modulus of K–P compounds by 74%, effectively withstanding the high strain induced by the potassiation process. Additionally, the bonding modulation reduces the formation energies of potassium phosphides, facilitating a deeper potassiation of the BP anode. As a result, the modified BP anode exhibits a high reversible capacity and extended operational lifespan, coupled with a high areal capacity. This work introduces a new perspective on overcoming the trade-off between low-strain and deep-potassiation in alloy anodes for the development of high-energy and stable potassium-ion batteries

Breaking Low-Strain and Deep-Potassiation Trade-Off in Alloy Anodes via Bonding Modulation for High-Performance K‑Ion Batteries

Alloy anode materials have garnered unprecedented attention for potassium storage due to their high theoretical capacity. However, the substantial structural strain associated with deep potassiation results in serious electrode fragmentation and inadequate K-alloying reactions. Effectively reconciling the trade-off between low-strain and deep-potassiation in alloy anodes poses a considerable challenge due to the larger size of K-ions compared to Li/Na-ions. In this study, we propose a chemical bonding modulation strategy through single-atom modification to address the volume expansion of alloy anodes during potassiation. Using black phosphorus (BP) as a representative and generalizing to other alloy anodes, we established a robust P–S covalent bonding network via sulfur doping. This network exhibits sustained stability across discharge–charge cycles, elevating the modulus of K–P compounds by 74%, effectively withstanding the high strain induced by the potassiation process. Additionally, the bonding modulation reduces the formation energies of potassium phosphides, facilitating a deeper potassiation of the BP anode. As a result, the modified BP anode exhibits a high reversible capacity and extended operational lifespan, coupled with a high areal capacity. This work introduces a new perspective on overcoming the trade-off between low-strain and deep-potassiation in alloy anodes for the development of high-energy and stable potassium-ion batteries