The emergence of high-entropy materials has inspired the exploration of novel materials in diverse technologies. In electrochemical energy storage, high-entropy design has shown advantageous impacts ...on battery materials such as suppressing undesired short-range order, frustrating energy landscape, decreasing volumetric change and reducing the reliance on critical metals. This comment addresses the definition and potential improper use of the term “high entropy” in the context of battery materials design, highlights the unique properties of high-entropy materials in battery applications, and outlines the remaining challenges in the synthesis, characterization, and computational modeling of high-entropy battery materials.
The tremendous improvement in performance and cost of lithium-ion batteries (LIBs) have made them the technology of choice for electrical energy storage. While established battery chemistries and ...cell architectures for Li-ion batteries achieve good power and energy density, LIBs are unlikely to meet all the performance, cost, and scaling targets required for energy storage, in particular, in large-scale applications such as electrified transportation and grids. The demand to further reduce cost and/or increase energy density, as well as the growing concern related to natural resource needs for Li-ion have accelerated the investigation of so-called “beyond Li-ion” technologies. In this review, we will discuss the recent achievements, challenges, and opportunities of four important “beyond Li-ion” technologies: Na-ion batteries, K-ion batteries, all-solid-state batteries, and multivalent batteries. The fundamental science behind the challenges, and potential solutions toward the goals of a low-cost and/or high-energy-density future, are discussed in detail for each technology. While it is unlikely that any given new technology will fully replace Li-ion in the near future, “beyond Li-ion” technologies should be thought of as opportunities for energy storage to grow into mid/large-scale applications.
In the synthesis of inorganic materials, reactions often yield non-equilibrium kinetic byproducts instead of the thermodynamic equilibrium phase. Understanding the competition between thermodynamics ...and kinetics is a fundamental step towards the rational synthesis of target materials. Here, we use in situ synchrotron X-ray diffraction to investigate the multistage crystallization pathways of the important two-layer (P2) sodium oxides Na
MO
(M = Co, Mn). We observe a series of fast non-equilibrium phase transformations through metastable three-layer O3, O3' and P3 phases before formation of the equilibrium two-layer P2 polymorph. We present a theoretical framework to rationalize the observed phase progression, demonstrating that even though P2 is the equilibrium phase, compositionally unconstrained reactions between powder precursors favour the formation of non-equilibrium three-layered intermediates. These insights can guide the choice of precursors and parameters employed in the solid-state synthesis of ceramic materials, and constitutes a step forward in unravelling the complex interplay between thermodynamics and kinetics during materials synthesis.
Abstract
In this paper we develop the stability rules for NASICON-structured materials, as an example of compounds with complex bond topology and composition. By first-principles high-throughput ...computation of 3881 potential NASICON phases, we have developed guiding stability rules of NASICON and validated the ab initio predictive capability through the synthesis of six attempted materials, five of which were successful. A simple two-dimensional descriptor for predicting NASICON stability was extracted with sure independence screening and machine learned ranking, which classifies NASICON phases in terms of their synthetic accessibility. This machine-learned tolerance factor is based on the Na content, elemental radii and electronegativities, and the Madelung energy and can offer reasonable accuracy for separating stable and unstable NASICONs. This work will not only provide tools to understand the synthetic accessibility of NASICON-type materials, but also demonstrates an efficient paradigm for discovering new materials with complicated composition and atomic structure.
High-entropy mechanism to boost ionic conductivity Zeng, Yan; Ouyang, Bin; Liu, Jue ...
Science (American Association for the Advancement of Science),
12/2022, Letnik:
378, Številka:
6626
Journal Article
Recenzirano
Odprti dostop
Advances in solid-state batteries have primarily been driven by the discovery of superionic conducting structural frameworks that function as solid electrolytes. We demonstrate the ability of ...high-entropy metal cation mixes to improve ionic conductivity in a compound, which leads to less reliance on specific chemistries and enhanced synthesizability. The local distortions introduced into high-entropy materials give rise to an overlapping distribution of site energies for the alkali ions so that they can percolate with low activation energy. Experiments verify that high entropy leads to orders-of-magnitude higher ionic conductivities in lithium (Li)-sodium (Na) superionic conductor (Li-NASICON), sodium NASICON (Na-NASICON), and Li-garnet structures, even at fixed alkali content. We provide insight into selecting the optimal distortion and designing high-entropy superionic conductors across the vast compositional space.
High-entropy (HE) ceramics, by analogy with HE metallic alloys, are an emerging class of solid solutions composed of a large number of species. These materials offer the benefit of large ...compositional flexibility and can be used in a wide variety of applications, including thermoelectrics, catalysts, superionic conductors and battery electrodes. We show here that the HE concept can lead to very substantial improvements in performance in battery cathodes. Among lithium-ion cathodes, cation-disordered rocksalt (DRX)-type materials are an ideal platform within which to design HE materials because of their demonstrated chemical flexibility. By comparing a group of DRX cathodes containing two, four or six transition metal (TM) species, we show that short-range order systematically decreases, whereas energy density and rate capability systematically increase, as more TM cation species are mixed together, despite the total metal content remaining fixed. A DRX cathode with six TM species achieves 307 mAh g
(955 Wh kg
) at a low rate (20 mA g
), and retains more than 170 mAh g
when cycling at a high rate of 2,000 mA g
. To facilitate further design in this HE DRX space, we also present a compatibility analysis of 23 different TM ions, and successfully synthesize a phase-pure HE DRX compound containing 12 TM species as a proof of concept.
Background
Vonoprazan‐amoxicillin (VA) dual therapy has been shown to achieve acceptable cure rates for treatment of Helicobacter pylori(H. pylori) in Japan. Its effectiveness in other regions is ...unknown. We aimed to explore the efficacy of VA dual therapy as first‐line treatment for H. pyloriinfection in China.
Methods
This was a single center, prospective, randomized clinical pilot study conducted in China. Treatment naive H. pyloriinfected patients were randomized to receive either low‐ or high‐dose amoxicillin‐vonoprazan consisting of amoxicillin 1 g either b.i.d. or t.i.d plus VPZ 20 mg b.i.d for 7 or 10 days. 13C‐urea breath tests were used to access the cure rate at least 4 weeks after treatment.
Results
Three hundred and twenty‐three patients were assessed, and 119 subjects were randomized. The eradication rates of b.i.d. amoxicillin for 7 and 10 days, t.i.d. amoxicillin for 7 and 10 days were 66.7% (16/24), 89.2% (33/37), 81.0% (17/21), and 81.1% (30/37) (p = .191) by intention‐to‐treat analysis, respectively, and 72.7% (16/22), 89.2% (33/37), 81.0% (17/21), and 81.1% (30/37) (p = .454) by per‐protocol analysis, respectively.
Conclusion
Neither 7‐ or 10‐day VA dual therapy with b.i.d. or t.i.d. amoxicillin provides satisfied efficacy as the first‐line treatment for H. pyloriinfection in China. Further optimization is needed.
We have investigated the phase transformation of bulk MoS2 crystals from the metastable metallic 1T/1T′ phase to the thermodynamically stable semiconducting 2H phase. The metastable 1T/1T′ material ...was prepared by Li intercalation and deintercalation. The thermally driven kinetics of the phase transformation were studied with in situ Raman and optical reflection spectroscopies and yield an activation energy of 400 ± 60 meV (38 ± 6 kJ/mol). We calculate the expected minimum energy pathways for these transformations using DFT methods. The experimental activation energy corresponds approximately to the theoretical barrier for a single formula unit, suggesting that nucleation of the phase transformation is quite local. We also report that femtosecond laser writing converts 1T/1T′ to 2H in a single laser pass. The mechanisms for the phase transformation are discussed.
The dynamic changes in land use/cover (LULC) significantly influence carbon storage, and assessing the vulnerability of carbon storage services in different basins is crucial for a comprehensive ...understanding of the impacts of human activities on ecosystems. The objective of this study is to propose a framework for optimizing LULC, simulating carbon storage, and assessing vulnerability by integrating the MOP, PLUS, and InVEST models. The results show that forests play a crucial role in enhancing carbon storage services in the Yangtze River Basin (YRB). Carbon storage in the upper reaches of the YRB is on the rise, counteracting the decrease in carbon storage caused by the expansion of built-up land. However, in the middle and lower reaches of the YRB, LULC has a negative impact on ecosystem carbon storage services. Under natural development scenarios, carbon storage is projected to decrease by 68.84 × 106 tons, leading to increased vulnerability of ecosystem carbon storage services. Under the scenario of ecological and economic balance, carbon storage is expected to increase by 97 × 106 tons. In the future, while restricting built-up land expansion, emphasis should be placed on expanding forest areas to more effectively enhance ecosystem services in basins.
Background
Vonoprazan is an emerging option for the treatment of Helicobacter pylori infection. We aimed to assess the research trends and hotspots of vonoprazan‐based therapy for H. pylori ...eradication through bibliometric analysis.
Materials and Methods
Vonoprazan‐based studies for eradicating H. pylori published from 2015 to 2023 were extracted from the Web of Science using a combination of the search terms “H. pylori” and “vonoprazan.” Each study was weighted according to the number of included patients.
Results
A total of 65 studies were included. Japan was the most productive and cooperative country, accounting for 69.2% of publications. Vonoprazan in combination with amoxicillin and clarithromycin (41.8%) was most used for eradicating H. pylori, followed by vonoprazan in combination with amoxicillin (20.4%) and vonoprazan in combination with amoxicillin and metronidazole (19.4%). The eradication rates for first‐line vonoprazan‐based therapies by intention to treat were: dual therapy (82.9%, 95% CI: 77.7%–88.0%), triple (83.3%, 95% CI: 79.7%–86.8%) and quadruple therapy (91.5%, 95% CI: 85.5%–97.4%), and per protocol: dual therapy (86.1%, 95% CI: 81.5%–90.7%), triple (89.3%, 95% CI: 87.9%–90.6%) and quadruple therapy (94.0%, 95% CI: 88.6%–99.4%). Vonoprazan was superior to proton pump inhibitors in triple therapy regarding empirical therapy (RR = 1.18, 95% CI, 1.14–1.22, p < 0.01) and clarithromycin‐resistant group (RR = 1.71, 95% CI, 1.33–2.20, p < 0.01), but there is no significant difference between triple therapy and dual therapy (RR = 1.02, 95% CI, 0.98–1.07, p = 0.33).
Conclusions
Vonoprazan has been widely used for H. pylori eradication. Further studies are needed to optimize the best duration and dosage of vonoprazan‐based regimens in different regions.
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