Journal of the Australian Ceramic Society最新文献

The development of inexpensive catalysts that perform extraordinarily well in the electrochemical oxygen evolution process (OER) is necessary for the quick development of renewable energy sources. To obtain a great effect of intrinsic activity and the exposure of interfacial active sites at a greater density is often recommended when designing active and effective catalysts for OER via water splitting to attain clean energy in the form of hydrogen. In present work, cobalt ferrite (CoFe₂O₄) and polyaniline (PANI) are combined to design cluster-based catalysts with robust efficiency. The CoFe₂O₄ nanoflakes in this instance are uniformly adorned with PANI to provide an electronic effect on the CoFe₂O₄ nanoflakes. Thus, the designed interface needs an overpotential of 151 mV for OER, which is steady for up to 80 h of testing. The exceptional activity and longstanding durability are a result of the higher revelation of active sites, and faster kinetic reactions. Furthermore, the resultant material shows a small 105 mV/dec Tafel slope, offering the outstanding performance. Hence, this work proposes a novel method for designing nanostructures and for quickly producing oxide heterostructures based on transition metals, which are useful for future electrochemical applications.

Graphical abstract

Here, a glassy based on 20K₂O–(20–X)Fe₂O₃–XK₂WO₄–60P₂O₅ system (X = 0.0 (GW-0.0), 2.5 (GW-2.5), 5.0 (GW-5.0), 10.0 (GW-10.0), 15.0 (GW-15.0), and 20.0 (GW-20.0) mol%) was synthesized by the melt-quenching technique. The structural characteristics, neutron and γ-ray attenuation competence of the prepared glasses were examined using the MCNP5 simulation code and Phy-X/PSD (Phy) software in the photon energy (Eγ) 0.015-15 MeV. XRD analysis established the non-crystalline nature of the glassy samples. The linear (µ) and mass (µ_m) attenuation coefficients possessed the order: GW-0.0 < GW-2.5 < GW-5.0 < GW-10.0 < GW-15.0 < GW-20.0. The GW-20.0 sample which has the highest content of K₂WO₄ possessed the lowest values half/tenth value layers, and mean free path. Within the studied energy range, the effective atomic number ((:{text{Z}}_{text{e}text{f}})) verified the values: 19.587–12.543 for GW-0.0, 23.165–13.233 for GW-2.5, 26.447–13.903 for GW-5.0, 32.258–15.187 for GW-10.0, 37.243–16.400 for GW-15.0, and 41.567–17.549 GW-20.0 glasses, respectively. Commercial glasses were found to have a lower fast neutron removal cross-section than the GW-X glasses. Among the prepared GW-X glasses, the GW-20.0 displays the best neutron shielding capability and the GW-0.0 the best gamma radiation shielding capability.

Additive manufacturing (AM) methods have sparked interest within the tissue engineering domain due to their adaptability and capacity to fabricate constructs featuring intricate macroscopic shapes and specific patterns. Recently, composite materials, characterized by distinct phases a continuous phase (matrix) and a reinforcing phase (filler)—have emerged as viable inks for AM processes, enabling the creation of scaffolds with enhanced biomimetic and bioactive properties. Notably, significant attention has been directed towards hydroxyapatite (HA)-reinforced composites, particularly for bone tissue engineering applications, leveraging HA’s chemical resemblance to native mineralized tissue components. This review delves into the utilization of AM techniques for processing HA-reinforced composites and biocomposites to fabricate scaffolds embedded with biological matrices, including cellular tissues. It examines recent research findings concerning the morphological, structural, and in vitro/in vivo biological characteristics of these materials. The review also categorizes the approaches based on the matrix nature used to incorporate HA reinforcements and fabricate tissue substitutes, offering a critical analysis of the current state of research and future prospects. This comprehensive overview aims to elucidate the strategies explored and challenges faced in this evolving field of materiomics.

Magnesia lightweight aggregates were synthesized by direct foaming method with light burned magnesia powder as raw material, sodium dodecyl benzene sulfonate (SDBS) as foaming agent and triethanolamine (TEA) as dispersant. Aqueous foams and magnesia foam slurry with foaming agent content of 3 wt% were prepared. The effects of different contents TEA (0.6 wt%, 1.0 wt%, 1.4 wt%, 1.8 wt%, and 2.2 wt%) on Zeta potential, viscosity, expansion ratio, contact angle, and surface tension of magnesia foam slurry were studied. The microstructure of aqueous foams and magnesia foam slurry were observed by optical microscope. After sintering at 1600 °C, the number and distribution of pores in the magnesia lightweight aggregates were analyzed by SEM. In aqueous foams, with the increase of TEA contents, the bubble liquid film became thicker and the shape became circle. In the magnesia foam slurry, when the TEA content was 1.4 wt%, the Zeta potential was 28.19 mV, the contact angle was 62.3°, and the surface tension was 45.2 mN∙m^− 1. The adsorption free energy of magnesia particles was about 7.3 × 10^− 9 J. The bubble size distribution was 31.48 μm to 114.30 μm. In magnesia lightweight aggregates, the average pore size was 30.98 μm to 95.43 μm.

Clay based Forsterite (Mg₂SiO₄-clay based) was synthesized using Halloysite nanotube clay via sol-gel method. The resultant materials were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), particle size analysis (PSA), and hardness analysis. The formation of Mg₂SiO₄-clay based nanoparticles was confirmed using X-ray diffraction and Fourier-transform infrared analysis. Mg₂SiO₄-clay based nanoparticles were treated at different high temperatures which are from 850 °C to 1050 °C. It was revealed that crystalline Mg₂SiO₄-clay based was formed at the lowest temperature (850 °C) and the different temperatures do not significantly affect the FTIR peaks. Moreover, the hardness and fracture toughness of Mg₂SiO₄-clay based was found to be higher than synth-Mg₂SiO_4, which are 1.03 ± 0.07 GPa and 5.7 ± 0.21 MPa m^1/2, respectively. It was also found that the fracture toughness of Mg₂SiO₄-clay based was higher than a few types of cortical bones and synthetic Hydroxyapatite. Other than that, Mg₂SiO₄-clay based displayed remarkable antibacterial properties which is critical criteria for implant materials. These findings suggest that the Mg₂SiO₄-clay based possesses good structural, mechanical, and antibacterial properties and might be suitable for potential bioimplant materials.

This paper studies the effect of centrifugation rotation rate on the compressive strength and microstructure of alkali-activated slag (AAS) paste. The results indicate that the compressive strength gradually improves with increase in centrifugation rotation rate and the maximum compressive strength is 71.8 MPa at 5000 rpm with increasing amplitude of 133.8% compared to the AAS paste without centrifugation. The flower clusters gels of C(N)-A-S-H including large proportion of N-A-S-H appear in the AAS paste with centrifugation rotation rates of 0 r/min. The layered gels mainly including the hydrotalcite phase and C(N)-A-S-H are found under the centrifugation rotation rates of 1000 r/min. The globule gels of C-A-S-H including small proportion of N-A-S-H appear in the AAS paste with centrifugation rotation rates of 3000 r/min and 5000 r/min. The more generation of large size globule gels of C-A-S-H is conducive to improving compressive strength of AAS paste. Furthermore, the increase in centrifugation rotation rate promotes the reaction of slag and generation of gel products, and improves the polymerization and cross-linking degree of gel products, causing the lower porosity and higher bulk density, eventually leading to the enhancement of compressive strength.