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Self-supporting metal-organic framework (MOF) with a hybrid structure has recently attracted significant interest as a novel electrocatalyst for water splitting. Herein, a binder-free 2D–3 D -hybrid P-doped MOF bifunctional water-splitting electrocatalyst on Ni foam (NF) was prepared through a one-pot hydrothermal process followed by phosphorization. The 2-amino-1,4-benzene dicarboxylic acid (BDC(NH 2)) and Mn/Co atoms were employed as organic ligands and center metal ions of the MOF, respectively. The as-fabricated P@Mn 1 Co 3 -BDC(NH 2)/NF displayed an overpotential of 102 mV for the hydrogen evolution reaction (HER), 310 mV for the oxygen evolution reaction (OER), and a cell voltage of 1.69 V at a current density of 10 mA cm-2 under alkaline conditions. The synergistic effect of the functionalized amino and heteroatoms (P) in the organic ligands could improve the electric environment of the active metal sites and promote the electron-transfer process during the reaction. The P@Mn 1 Co 3 -BDC(NH 2)/NF demonstrated great reactive activity and excellent catalytic stability as a promising electrocatalyst for overall water splitting. • A 2D-3D-hybrid P-doped MOF catalyst with interconnected nanosheets and porous nanospheres has been fabricated. • The amino functionalization leads to reactions between NH 2 groups and OH− ions to promote the charge transfer process. • The P elements modulate the electric environment of Co sites and promote electron transfer during water splitting. • The effect of heteroatom, amino functionalization, and 2D-3D-hybrid structure endows the catalyst with great performance. [ABSTRACT FROM AUTHOR]

Hierarchically porous titania (TiO 2 ) xerogel monoliths were successfully synthesized by a facile sol–gel process accompanied by phase separation in the presence of formamide (FA) and triblock copolymer F127, followed by ambient pressure drying to remove the solvents. Gelation of the system has been mediated by FA, while F127 enhances a phase-separation. The resultant dried xerogel presents a hierarchically porous structure constructed by large macropores and mesoporous skeletons, which exhibits a high BET surface area of 444 m 2 g −1 . Heat-treatment at 800 °C results in the formation of the crystalline anatase phase with high thermal stability, without spoiling the macrostructure. The as- prepared porous TiO 2 xerogel displays superior electrochemical properties, and the specific capacity of TiO 2 xerogel could remain over 114 mAh g −1 (69 mAh cm −3 ) at 1 C after 100 cycles, representing a good cycling stability. [ABSTRACT FROM AUTHOR]

Ethyl cellulose porous spheres (ECPSs) loaded with superparamagnetic iron oxide nanoparticles (SPIONs) have been successfully synthesized via a physical method in oil-in-water (O/W) emulsion. The as-prepared ECPSs possess open pores in the shell and interconnected pores inside the spheres by means of phase separation. The SPIONs with an average size of around 5 nm synthesized by co-precipitation method are added into oil phase precursor in the preparation of ECPSs to synthesize the ECPSs-SPIONs. The loading of SPIONs does not change the morphology of ECPSs, while endows the ECPSs with high ferromagnetic properties at room temperature. The resultant ECPSs-SPIONs can be easily separated from dispersion liquid or driven to specific sites under an external magnet. [ABSTRACT FROM AUTHOR]

MnO/C composites with hollow porous structure have been successfully synthesized by a facile biotemplating method combine with chemical bath deposition (CBD) method followed by calcination treatment. The natural porous lotus pollen grains are used as the biotemplate as well as the carbon source. The biological carbon could effectively enhance the electrical conductivity of MnO and cushion the strain arising from the charge/discharge cycles. Due to the unique structure, MnO/C composites exhibit a high reversible specific capacity of 730 mAh g −1 at a current density of 0.1 A g −1 with excellent cycling stability. Even at a high current density of 3 A g −1 , a remarkable reversible capacity of 430 mAh g −1 could still be delivered. [ABSTRACT FROM AUTHOR]

• Silica sol and PEDOT:PSS improves film conductivity, flatness, uniformity and stability. • Transparent conductive film get a sheet resistance of 12 Ω·sq−1 and transmittance of 87.5%. • The transparent film heater achieves 99 °C at 15 V with a good defogging function. A robust, flexible and transparent silver nanowires(AgNWs)/silica sol/poly(3,4-ethylene dioxythiophene)/poly(styrene sulfonate) (PEDOT:PSS) composite film was fabricated for film heater via spray-coating AgNWs ink, silica sol and PEDOT:PSS onto the surface of polyethylene glycol terephthalate substrate in turn. Silica sol nanoparticles are absorbed around the AgNWs to improve the connection between AgNWs by capillary effect, and the PEDOT:PSS covers on the surface of AgNWs/silica sol layer to increase the network conductive paths and protect the AgNWs/silica sol layer. The AgNWs/silica sol/PEDOT:PSS composite film shows a sheet resistance of 12 Ω/sq, a transmittance of 87.5% at 550 nm and a Joule heating temperature of 99 °C at 15 V. The composite film with high mechanical stability, low surface roughness and corrosion resistance is promisingly used in window defrost and deicer system. [ABSTRACT FROM AUTHOR]

Abstract: Bioactive glass ceramics (BGCs) have different rates of biodegradation and mechanical properties depending on their chemical compositions and sintering temperatures. The present study was aimed to develop the boron-rich, phosphorus-low CaO–SiO2–P2O5–B2O3 bioactive glasses (BG-Bx, X=0, 10, 20) potentially for improving the mechanical properties of BGCs via low-temperature co-fired process. The B2O3-free BG-B0 shrunk well at ~726°C and melted at over 1050°C, while the onset shrinking and melting temperatures of the 20mol% B2O3-doped BG-B20 was lowered to ~648°C and ~952°C, respectively. The BG-B20 thermally treated at 850–950°C was transformed into wollastonite and calcium borate, and crystallization decreased the kinetics but did not inhibit the development of hydroxyapatite on their powder and disc surface when immersed in simulated body fluid. The in vitro degradation in Tris buffer confirmed that the degradation rate markedly increased with increasing boron content in BG-Bx. The compressive strength and flexural strength of the 10% BG-B20-reinforced 45S5 porous BGC sintered at 850°C was nearly four times than that of 45S5 porous constructs. These studies suggest that the boron-rich, phosphorus-low CaO–SiO2–P2O5–B2O3 system is a promising biomaterial and potential low temperature co-fired aid for improving the mechanical and biological properties of porous BGCs. [Copyright &y& Elsevier]

Three-dimensional (3D) Nitrogen-doped carbon coated hierarchically porous silicon (hp-Si@NC) composite with cocontinuous skeletons and abundant interconnected macropores was prepared by a sol-gel route, followed by a magnesiothermic reduction and a polydopamine pyrolyzation. The BET specific surface area and pore volume of the obtained hp-Si@NC composite are calculated to be around 220.4 m2·g─1 and 0.247 cm3·g─1, respectively. Both hierarchically porous Si monolith and hp-Si@NC composite possess great electrochemical performances. The hierarchically porous Si monolith exhibits an initial discharge and charge capacity of about 1943 and 1621 mAh·g─1, and maintains a reversible capacity of about 125 mAh·g─1 in the 100th cycle. The hp-Si@NC composite reveals a discharge capacity of about 1077 mAh·g─1 and a charge capacity of 723 mAh·g─1 in the first cycle, and a reversible capacity of around 700 mAh·g─1 remains after 100 cycles. The coulombic efficiency increases from 67.1% in the first cycle to 97% in the second cycle and to 99% in the 100th cycle, with a great rate performance. All these favorable electrochemical characterizations benefit from unique pore structure and N-doped carbon layer. The hp-Si@NC composite obtained by integrating with sol-gel process, magnesiothermic reduction and polydopamine pyrolyzation can be promisingly applied as an anode in Li-ion batteries with a bright prospect. • Three-dimensional hierarchical porous Si monolith is prepared by a magnesiothermic reduction. • The hp-Si@NC composite possesses interconnected macropores and co-continuous skeletons. • The hierarchically porous hp-Si@NC shows excellent cycling stability and rate capability. [ABSTRACT FROM AUTHOR]

Macroporous terbium-doped Ca 12 Al 14 O 32 Cl 2 (C12A7:Tb3+) monoliths were synthesized via a sol-gel route accompanied by phase separation, and the luminescence performances and detection of Ag+ in water of the C12A7:Tb3+ monoliths were investigated in detail. The simulation of the hydrolysis and dimerization reactions of C12A7:Tb3+shows that the hydrolysis and dimerization of Tb3+ are prior to Al3+, and the doped Tb3+ will affect the sol-gel transition of the system. The addition of Tb element changes the macrostructure derived from phase separation and sol-gel transition, and decreases the macropore size of C12A7 monolith. Heat treatment allows the formation of a single mayenite phase C12A7:Tb3+ without spoiling the macrostructure, and the Tb3+ ions replace the position of the Ca2+ ions of the "cage" structure without destroying the lattice structure of C12A7. The luminescence intensity of C12A7:3%Tb3+ monolith reaches the maximum, and the corresponding macropore size and porosity are 0.3 μm and 79% respectively. High luminescence intensity of C12A7:Tb3+ monolith is attributed to higher scattering light and wonderful high temperature stability derived from the macrostructure. The obtained macroporous C12A7:Tb3+ material has a sensitive response to Ag+ ions, and can become a promising fluorescence sensor for the detection of Ag+ ions. Image 1 • Macroporous terbium-doped Ca 12 Al 14 O 32 Cl 2 (C12A7:Tb3+) monoliths have been synthesized via a sol-gel route. • The luminescence performances and detection of Ag+ in water of the C12A7:Tb3+ monoliths were investigated in detail. • By DFT calculation of hydrolysis and polymerization of Tb3+ and Al3+, Tb influence to macroporous structure was analyzed. [ABSTRACT FROM AUTHOR]

Bimetallic atom catalysts exhibit ultra-high oxygen electrocatalytic activity by harnessing mutual promotion and synergistic effects between adjacent metal active centers, surpassing the performance of single metal atomic catalysts. Herein, FeNi atom pairs protected by hierarchical porous annular carbon grids (P-FeNi-NPC) are introduced using a mediator-assisted MOFs-derived strategy. The introduction of the multi-block copolymer P123 ensures the uniform confinement and dispersion of metal ions, followed by thermal decomposition to form a "planetary-ring-like" carbon framework that anchors the bimetallic atomic pairs in the active region. The homogeneous distribution of adjacent Fe-N 4 and Ni-N 4 active sites significantly enhances catalytic activity and stability. Leveraging unique electronic and geometric structures, the resulting P-FeNi-NPC catalyst demonstrates exceptional ORR and OER activities with an ΔE value of 0.705 (E 1/2 = 0.845 V, E j = 10 = 1.55 V). Theoretical calculations unveil that FeNi bimetallic sites loaded on nitrogen-doped carbon frameworks with specific curvature effectively modulate the energy of d-band centers, thus balancing the free energy of oxygen-containing intermediates. This study presents a novel and versatile approach for synthesizing advanced bifunctional catalysts, poised to drive the future development of Zn-air batteries., (© 2024 Wiley‐VCH GmbH.)

The purpose of this study is to prepare monodisperse silica mesoporous microspheres with narrow pore size distribution to promote their application in the field of liquid chromatography. An improved emulsion method was used to prepare silica mesoporous microspheres, and the rotary evaporation temperature, emulsification speed, dosage of porogen DMF, and dosage of the catalyst NH 3 ·H 2 O were optimized. Subsequently, these microspheres were respectively treated by alkali-heating, calcination, and sieving. The D 50 (particle size at the cumulative particle size distribution percentage of 50%) of as-prepared silica mesoporous microspheres is 26.3 μm, and the D 90 /D 10 (the ratio of particle size at a cumulative particle size distribution percentage of 90% to a cumulative particle size distribution percentage of 10%) is 1.94. The resultant silica mesoporous microspheres have distinctive pore structures, with a pore volume of more than 1.0 cm 3 /g, an average pore size of 11.35 nm, and a median pore size of 13.4 nm. The silica mesoporous microspheres with a large particle size, uniform particle size distribution, large average pore size and pore volume, and narrow mesopore size distribution can basically meet the requirements of preparative liquid chromatographic columns.

Silicon carbide (SiC) ceramics with high bending strength were prepared by hot pressing sintering (HPS) with yttrium aluminum garnet (Y 3 Al 5 O 12 , YAG) as sintering additive, and the effects of YAG content and sintering temperature on the sintering behavior, microstructure and mechanical properties of SiC ceramics were investigated in detail. The uniform distribution of YAG to form a liquid phase and the driving force provided by hot pressing sintering decrease the sintering temperature, improve the densification of SiC ceramics, and refine the crystal size. By means of suitable sintering conditions with the additional amount of YAG of 5 wt%, the sintering temperature of 1950 °C and a pressure of 30 MPa, the resultant SiC/YAG composite ceramics possesses high sintering and mechanical properties with the relative density of 98.53%, the bending strength of 675 MPa, the Vickers hardness of up to 17.92 GPa, and the elastic modulus of 386 GPa. The as-prepared SiC/YAG composite ceramics are promisingly used as the dry gas seal materials in the centrifugal compressors.

The aim of this study is to reduce the manufacturing cost of a hydrophobic and heat-insulating silica aerogel and promote its industrial application in the field of thermal insulation. Silica aerogels with hydrophobicity and thermal-insulation capabilities were synthesized by using water-glass as the silicon source and supercritical drying. The effectiveness of acid and alkali catalysis is compared in the formation of the sol. The introduction of sodium methyl silicate for the copolymerization enhances the hydrophobicity of the aerogel. The resultant silica aerogel has high hydrophobicity and a mesoporous structure with a pore volume exceeding 4.0 cm 3 ·g -1 and a specific surface area exceeding 950 m 2 ·g -1 . The obtained silica aerogel/fiber-glass-mat composite has high thermal insulation, with a thermal conductivity of less than 0.020 W·m -1 ·K -1 . The cost-effective process is promising for applications in the industrial preparation of silica aerogel thermal-insulating material.

Energy storage via anionic redox provides extra capacity for lithium-rich manganese-based oxide cathodes at high voltage but causes gradual structural collapse and irreversible capacity loss with generation of O n - (0 ≤ n < 2) species upon deep oxidation. Herein, the stability and reversibility of anionic redox reactions are enhanced by a simple sulfur-assisted surface modification method, which not only modulates the material's energy band allowing feasible electron release from both bonding and antibonding bands, but also traps the escaping O n - via an as-constructed SnS 2- x - σ O y coating layer and return them to the host lattice upon discharge. The regulation of anionic redox inhibits the irreversible structural transformation and parasitic reactions, maintaining the specific capacity retention of as-modified cathode up to 94% after 200 cycles at 100 mA g -1 , along with outstanding voltage stability. The reported strategy incorporating energy band modulation and oxygen trapping is promising for the design and advancement of other cathodes storing energy through anion redox., (© 2023 Wiley-VCH GmbH.)

Cellulose aerogels are the latest generation of aerogels and have also received extensive attention due to their renewable and biocompatible properties. Herein, cellulose aerogel was facilely prepared by using NaOH/urea solution as solvent, raising the temperature to control gelation and drying wet gel sequentially. With NaOH/urea solution as solvent, the cellulose concentration has an important impact on the micromorphology of cellulose aerogels, while the aging time rarely affects the micromorphology. The appropriate solvent and drying method allow the formation of different cellulose crystalline structures. Different from the Cellulose Ⅰ crystalline structure of raw cellulose powder, the cellulose phase of as-prepared cellulose aerogels belongs to the Cellulose Ⅱ crystalline structure, and to some extent the pyrolysis temperature is also lower than that of raw cellulose powder. The resultant cellulose aerogel prepared by using NaOH/urea solution as solvent and freeze-drying has a uniform macroporous structure with a macropore size of 1~3 µm.

High-efficiency, good electrical conductivity and excellent performance electrocatalysts are attracting growing attention in the field of overall water splitting. In order to achieve the desirable qualities, rational construction of the structure and chemical composition of electrocatalysts is of fundamental importance. Herein, petal-like structure Ni 0.33 Co 0.67 P shells grown on conductive silver nanowires (Ag NWs) cores as bifunctional electrocatalysts for overall water splitting were synthesized through a facile hydrothermal method and phosphorization. The resultant three-dimensional core-shell petal-like structure Ag NWs@Ni 0.33 Co 0.67 P possesses excellent catalytic activities in alkaline conditions with the overpotential of 259 mV for the oxygen evolution reaction (OER), 121 mV for the hydrogen evolution reaction (HER) and a full cell voltage of 1.64 V to reach the current density of 10 mA cm -2 . Highly conductive Ag NWs as cores and high surface area petal-like Ni 0.33 Co 0.67 P as shells can endow outstanding catalytic performance for the bifunctional electrocatalyst. Thus, the synthetic strategy of the three-dimensional core-shell structure Ag NWs@Ni 0.33 Co 0.67 P considerably advances the practice of Ag NWs toward electrocatalysts.

Designing elaborate nanostructures and engineering defects have been promising approaches to fabricate cost-efficient electrocatalysts toward overall water splitting. In this work, a controllable Prussian-blue-analogue-sacrificed strategy followed by an annealing process to harvest defect-rich Ni-Fe-doped K 0.23 MnO 2 cubic nanoflowers (Ni-Fe-K 0.23 MnO 2 CNFs-300) as highly active bifunctional catalysts for oxygen and hydrogen evolution reactions (OER and HER) is reported. Benefiting from many merits, including unique morphology, abundant defects, and doping effect, Ni-Fe-K 0.23 MnO 2 CNFs-300 shows the best electrocatalytic performances among currently reported Mn oxide-based electrocatalysts. This catalyst affords low overpotentials of 270 (320) mV at 10 (100) mA cm -2 for OER with a small Tafel slope of 42.3 mV dec -1 , while requiring overpotentials of 116 and 243 mV to attain 10 and 100 mA cm -2 for HER respectively. Moreover, Ni-Fe-K 0.23 MnO 2 CNFs-300 applied to overall water splitting exhibits a low cell voltage of 1.62 V at 10 mA cm -2 and excellent durability, even superior to the Pt/C||IrO 2 cell at large current density. Density functional theory calculations further confirm that doping Ni and Fe into the crystal lattice of δ-MnO 2 can not only reinforce the conductivity but also reduces the adsorption free-energy barriers on the active sites during OER and HER., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Robust graphene/silver nanowires (AgNWs) hybrid aerogels were fabricated by facile processes including mixing directly, reducing, and ambient pressure drying. The mechanical properties and electromagnetic interference (EMI)-shielding performance of the resultant hybrid aerogels were investigated in detail. Because silver nanowires with a high aspect ratio have been acting as crosslinkers to bridge two-dimensional graphene sheets, a highly porous and electrically conducting framework can resist high external loading to prevent major deformation and act as an express way for electron transport. Consequently, the hybrid aerogel exhibits large mechanical strength of 42 kPa, 35 times larger than that of the neat reduced graphene oxide aerogel (1.2 kPa), which can resist great damage. More importantly, the as-prepared aerogel possesses high EMI-shielding performance of up to ∼45.2 dB due to its unique nanostructure and good electrical properties. These results indicate that graphene/AgNWs hybrid aerogel prepared using this simplified method promises to be an ideal functional component for mechanically robust and high-performance EMI-shielding nanocomposites., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)