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Owing to their high-voltage stabilities, halide superionic conductors such as Li3YCl6 recently emerged as promising solid electrolyte (SE) materials for all-solid-state batteries (ASSBs). It has been shown that by either introducing off-stoichiometry in solid-state (SS) synthesis or using a mechanochemical (MC) synthesis method the ionic conductivities of Li3-3xY1+xCl6 can increase up to an order of magnitude. The underlying mechanism, however, is unclear. In the present study, we adopt a hopping frequency analysis method of impedance spectra to reveal the correlations in stoichiometry, crystal structure, synthesis conditions, Li+ carrier concentrations, hopping migration barriers, and ionic conductivity. We show that unlike the conventional Li3YCl6 made by SS synthesis, mobile Li+ carriers in the defect-containing SS-Li3-3xY1+xCl6 (0 < x < 0.17) and MC-Li3-3xY1+xCl6 are generated with an activation energy and their concentration is dependent on temperature. Higher ionic conductivities in these samples arise from a combination of a higher Li+ carrier concentration and lower migration energy barriers. A new off-stoichiometric halide (Li2.61Y1.13Cl6) with the highest ionic conductivity (0.47 mS cm-1) in the series is discovered, which delivers exceptional cycling performance (∼90% capacity retention after 1000 cycles) in ASSB cells equipped with an uncoated high-energy LiNi0.8Mn0.1Co0.1O2 (NMC811) cathode. This work sheds light on the thermal activation process that releases trapped Li+ ions in defect-containing halides and provides guidance for the future development of superionic conductors for all-solid-state batteries.

The incorporation of functional building blocks to construct functionalized and highly porous covalent triazine frameworks (CTFs) is essential to the emerging adsorptive-involved field. Herein, a series of amide functionalized CTFs (CTF-PO71) have been synthesized using a bottom-up strategy in which pigment PO71 with an amide group is employed as a monomer under ionothermal conditions with ZnCl2 as the solvent and catalyst. The pore structure can be controlled by the amount of ZnCl2 to monomer ratio. Benefitting from the highly porous structure and amide functionalities, CTF-PO71, as a sulfur cathode host, simultaneously demonstrates physical confinement and chemical anchoring of sulfur species, thus leading to superior capacity, cycling stability, and rate capability in comparison to unfunctionalized CTF. Meanwhile, as an adsorbent of organic dye molecules, CTF-PO71 was demonstrated to exhibit strong chemical interactions with dye molecules, facilitating adsorption kinetics and thereby promoting the adsorption rate and capacity. Furthermore, the dynamic adsorption experiments of organic dyes from solutions showed selectivity/priority of CTF-PO71s for specific dye molecules.

The aligned one-dimensional channels found in covalent organic frameworks offer a unique space for energy storage. However, physical isolation of sulfur in the channels is not sufficient to prevent the shuttle of lithium-sulfide intermediates that eventually results in a poor performance of lithium-sulfur energy storage. Herein, we report a strategy based on imine-linked frameworks for addressing this shuttle issue by covalently engineering polysulfide chains on the pore walls. The imine linkages can trigger the polymerization of sulfur to form polysulfide chains and anchor them on the channel walls. The immobilized polysulfide chains suppress the shuttle effect and are highly redox active. This structural evolution induces multifold positive effects on energy storage and achieves improved capacity, sulfur accessibility, rate capability and cycle stability. Our results suggest a porous platform achieved by pore wall engineering for tackling key issues in energy storage.

As a mine rock-breaking technique, hydraulic fracturing technology can reduce the amount of explosives used, which enhance safety and reduce environmental pollution in mines. After precutting along the borehole axis, hydraulic fractures will expand along the precutting direction within a certain range and reduce initiation pressure. These hydraulic fractures cut through the rock mass, reducing its integrity and weakening its mechanical properties. Hydraulic fracturing with axially symmetric intersecting precut fractures not only controls the multi-directional propagation of fractures but also increases the fractures within rock mass. The lattice method simulated the hydraulic fracturing process, focusing on the parameters like angles between precut fractures and the minimum horizontal principal stress, the maximum horizontal principal stress, and angles between intersecting precut fractures. Results indicate that the hydraulic fractures propagate along intersecting precut fractures, forming main and interconnected secondary fractures. The directional cutting effect is influenced by the number of secondary fractures. With the increase in the angle between precut fractures and the minimum horizontal principal stress, the maximum horizontal principal stress, the angle between precut fractures, the area of secondary fractures decreased, and the expansion extent of main fractures along the precut fractures increased, indicating better directional effects. The study identifies relationships between initiation time, initiation pressure, and parameters. These findings provide valuable technical guidance for designing on-site construction plans for hydraulic fracturing projects involving intersecting precut fractures. [ABSTRACT FROM AUTHOR]

The rapid evolution of clinical medicine, materials science, and regenerative medicine has rendered traditional implantable scaffolds inadequate for addressing the complex therapeutic demands of various diseases. Currently, implantable scaffolds in clinical practice are mainly made of metal, with the disadvantages of high stiffness, poor toughness, and low deformation. This paper offers a thorough review of shape memory scaffolds (SMSs), emphasizing their distinctive self‐recovery and adaptive functionalities that enhance compatibility with injured tissues, surpassing the capabilities of conventional metallic biomaterials. It delves into the limitations of current clinical scaffolds and the requisite performance metrics for effective implants and outlines the essential materials and fabrication methods for SMSs. Moreover, we enumerate the biomedical applications of SMMs with different response types, including thermology‐responsive, water‐responsive, and light‐responsive. The discussion extends to the burgeoning applications of SMSs in biomedical engineering, including their utility in bone tissue engineering, cardiovascular stenting, tubular structures, and cardiac patches, which underscore their potential in minimally invasive procedures and dynamic tissue interactions. This review concludes with an analysis of current challenges and prospects, providing valuable insights for developing and applying SMSs in the biomedical sector. [ABSTRACT FROM AUTHOR]

Combining metal–organic frameworks (MOFs) with other functional materials can effectively improve the third‐order nonlinear optical (NLO) performances of MOFs. In this study, two distinct functional materials are selected and a PANI@MIL‐101(Cr)@CeO2 composite is successfully synthesized. The test results of third‐order NLO indicate that introducing PANI regulates the distribution of π electron clouds within the structure of the composite. Additionally, the core@shell structure formed by PANI@MIL‐101(Cr) and CeO2 promotes charge transfer and improves charge transfer efficiency under the weak heterojunction interaction, thereby enhancing nonlinear absorption and refractive signals. Under the double synergistic action of interior and exterior, a new charge transfer occurs between the components of the composite, resulting in excellent third‐order NLO performances. This study indicates that encapsulating polymer and loading metal oxides can effectively improve the NLO response of MOFs, which offers a new idea for more research on multiphase NLO materials. [ABSTRACT FROM AUTHOR]

The endometrium is a unique human tissue with an extraordinary ability to undergo a hormone‐regulated cycle encompassing shedding, bleeding, scarless repair, and regeneration throughout the female reproductive cycle. The cyclical repair and regeneration of the endometrium manifest as changes in endometrial epithelialization, glandular regeneration, and vascularization. The mechanisms encompass inflammation, coagulation, and fibrinolytic system balance. However, specific conditions such as endometriosis or TCRA treatment can disrupt the process of cyclical endometrial repair and regeneration. There is uncertainty about traditional clinical treatments' efficacy and side effects, and finding new therapeutic interventions is essential. Researchers have made substantial progress in the perspective of regenerative medicine toward maintaining cyclical endometrial repair and regeneration in recent years. Such progress encompasses the integration of biomaterials, tissue‐engineered scaffolds, stem cell therapies, and 3D printing. This review analyzes the mechanisms, diseases, and interventions associated with cyclical endometrial repair and regeneration. The review discusses the advantages and disadvantages of the regenerative interventions currently employed in clinical practice. Additionally, it highlights the significant advantages of regenerative medicine in this domain. Finally, we review stem cells and biologics among the available interventions in regenerative medicine, providing insights into future therapeutic strategies. [ABSTRACT FROM AUTHOR]