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High skeletal titanium content, open mesoporous TS-1 titanosilica molecular sieves with more accessible active centres exhibit higher catalytic activity, target product selectivity and resistance to coking deactivation in green catalytic oxidation reactions using hydrogen peroxide as oxidant. In this paper, TS-1 titania-silica molecular sieves without anatase, with the highest theoretical skeletal titanium content (2.0 wt%) and open mesopores (mesopore volume 0.71 cm3/g) were synthesised based on the ageing dry gel limited domain conversion method invented in previous research work. The intrinsic kinetics of the catalytic reaction of phenol with hydrogen peroxide for direct hydroxylation of benzenes was investigated. The effects of stirring rate, phenol concentration, hydrogen peroxide concentration, catalyst dosage and reaction temperature on the initial conversion rate of phenol were investigated, and the experimental data were fitted with a power function equation to obtain the intrinsic kinetic equation of the catalyst (r=2.98×106 exp (−56.43×103RT)c1.07(Phenol)c0.10(H2O2))\left( {{\rm{r}} = 2.98 \times {{10}^6}\,\exp \,\left( { - {{56.43 \times {{10}^3}} \over {RT}}} \right){c^{1.07}}\left( {{\rm{Phenol}}} \right){c^{0.10}}\left( {{{\rm{H}}_2}{{\rm{O}}_2}} \right)} \right). Under the condition of eliminating the effect of internal and external diffusion, the reaction was 1.07 and 0.10 for phenol and hydrogen peroxide, respectively, with a reaction activation energy of 56.43 kJ/mol. This study provides a theoretical basis for the reactor and process design of hydroxylation of phenol to benzenediol based on this new catalyst.

The outstanding thermal, chemical, and mechanical properties of ceramic membranes have attracted increasing attention, offering advantages over polymer and metal counterparts. Exploring the specialized applications of ceramic membranes through various preparation methods poses a daunting challenge for contemporary researchers. Traditional preparation methods are essentially unable to meet the requirements of complex membrane structures. For instance, in ceramic fuel cell applications, cells composed of ceramic membrane materials exhibit high resistance and low conductivity, which seriously hinders the progress of new high-performance ceramic fuel cells. Therefore, it is necessary to improve preparation methods to improve the electrochemical performance of devices composed of ceramic membrane materials. In recent years, breakthroughs in various new processing technologies have propelled the performance of ceramic membrane devices. This paper will focus on the following aspects. Firstly, traditional preparation methods and advanced preparation methods of ceramic membrane materials will be discussed. Secondly, high-performance ceramic membrane materials prepared by different advanced preparation methods are introduced, and the electrochemical properties of the devices composed of ceramic membrane materials are elaborated in combination with different testing and characterization methods. Finally, the prospects and future direction of the preparation of ceramic membrane materials by advanced preparation methods are summarized. [ABSTRACT FROM AUTHOR]

Research has been conducted on solid oxide fuel cells (SOFCs) for their fuel flexibility, modularity, high efficiency, and power density. However, the high working temperature leads to the deterioration of materials and increased operating costs. Considering the high protonic conductivity and low activation energy, the proton conducting SOFC, i.e., the protonic ceramic fuel cell (PCFC), working at a low temperature, has been wildly investigated. The PCFC is a promising state-of-the-art electrochemical energy conversion system for ecological energy; it is characterized by near zero carbon emissions and high efficiency, and it is environment-friendly. The PCFC can be applied for the direct conversion of various renewable fuels into electricity at intermediate temperatures (400–650 °C). The construction of the PCFC directly affect its properties; therefore, manufacturing technology is the crucial factor that determines the performance. As a thinner electrolyte layer will lead to a lower polarization resistance, a uniformly constructed and crack-free layer which can perfectly bond to electrodes with a large effective area is challenging to achieve. In this work, different fabrication methods are investigated, and their effect on the overall performance of PCFCs is evaluated. This article reviews the recent preparation methods of PCFCs, including common methods, 3D printing methods, and other advanced methods, with summarized respective features, and their testing and characterization results. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate the feasibility of an innovative method to fabricate flexibly embedded microchannels in bulk ceramics of complex geometries. This innovative method is an integration of extrusion freeforming (EFF) and picosecond (PS) laser machining. The bulk ceramic green body of complex geometries was fabricated using the extrusion method. After one green layer was extruded, in‐plane microchannels with variable cross‐section sizes and aspect ratios were fabricated using a picosecond laser. After the microchannels were fabricated, a cover layer was extruded. The green state processed structures ceramics were pressurelessly sintered to a bulk density of ~94%. In this paper, sinuous channels, channel networks, and patterns have been demonstrated. Vertical channels can also be drilled using the picosecond laser layer‐by‐layer with uniform diameters. The wall between the neighboring channels can be as thin as ~60 μm without any observable defects after firing. With the correct paste rheology, the cover layer did not sag into the microchannels and the bonding between layers was excellent. We did not observe any debonding between layers. During extrusion, the gaps between the adjacent filaments can be eliminated by controlling the filament spacing and the distance between needle tip and substrate. After firing, microchannels did not distort or collapse. The laser can cut through multiple layers without damage to the bonding between layers. Due to the uniform shrinkage during pressureless sintering, the green shapes of the microchannels were well preserved. [ABSTRACT FROM AUTHOR]

Laser reactive sintering enables quick and efficient bottom‐up fabrication of a wide range of ceramic‐based cells. This article demonstrates laser sintering of La0.8Sr0.2CrO3‐δ interconnects for solid‐oxide fuel cells. The rapid processing is also advantageous for densification due to reduced material sublimation. More details can be found in article number 2000364 by Jianhua Tong, Kyle S. Brinkman, and co‐workers. [ABSTRACT FROM AUTHOR]