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1.
Environ Sci Technol ; 58(24): 10863-10873, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38842426

RESUMO

Electrochemical nitrate reduction (NO3RR) provides a new option to abate nitrate contamination with a low carbon footprint. Restricted by competitive hydrogen evolution, achieving satisfied nitrate reduction performance in neutral media is still a challenge, especially for the regulation of this multielectron multiproton reaction. Herein, facile element doping is adopted to tune the catalytic behavior of IrNi alloy nanobranches with an unconventional hexagonal close-packed (hcp) phase toward NO3RR. In particular, the obtained hcp IrNiCu nanobranches favor the ammonia production and suppress byproduct formation in a neutral electrolyte indicated by in situ differential electrochemical mass spectrometry, with a high Faradaic efficiency (FE) of 85.6% and a large yield rate of 1253 µg cm-2 h-1 at -0.4 and -0.6 V (vs reversible hydrogen electrode (RHE)), respectively. In contrast, the resultant hcp IrNiCo nanobranches promote the formation of nitrite, with a peak FE of 33.1% at -0.1 V (vs RHE). Furthermore, a hybrid electrolysis cell consisting of NO3RR and formaldehyde oxidation is constructed, which are both catalyzed by hcp IrNiCu nanobranches. This electrolyzer exhibits lower overpotential and holds the potential to treat polluted air and wastewater simultaneously, shedding light on green chemical production based on contaminate degradation.


Assuntos
Nitratos , Oxirredução , Nitratos/química , Técnicas Eletroquímicas , Catálise , Metais/química
2.
Micron ; 185: 103678, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38941681

RESUMO

The rich potential of two-dimensional materials endows them with superior properties suitable for a wide range of applications, thereby attracting substantial interest across various fields. The ongoing trend towards device miniaturization aligns with the development of materials at progressively smaller scales, aiming to achieve higher integration density in electronics. In the realm of nano-scaling ferroelectric phenomena, numerous new two-dimensional ferroelectric materials have been predicted theoretically and subsequently validated through experimental confirmation. However, the capabilities of conventional tools, such as electrical measurements, are limited in providing a comprehensive investigation into the intrinsic origins of ferroelectricity and its interactions with structural factors. These factors include stacking, doping, functionalization, and defects. Consequently, the progress of potential applications, such as high-density memory devices, energy conversion systems, sensing technologies, catalysis, and more, is impeded. In this paper, we present a review of recent research that employs advanced transmission electron microscopy (TEM) techniques for the direct visualization and analysis of ferroelectric domains, domain walls, and other crucial features at the atomic level within two-dimensional materials. We discuss the essential interplay between structural characteristics and ferroelectric properties on the nanoscale, which facilitates understanding of the complex relationships governing their behavior. By doing so, we aim to pave the way for future innovative applications in this field.

3.
Inorg Chem ; 63(26): 12350-12359, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38887050

RESUMO

Hybrid metal halide materials with charming phase transition behaviors have attracted considerable attention. In former works, much attention has been focused on the phase transition triggered by the order-disorder or displacement motions of the organic component. However, manipulating the variation of the inorganic component to achieve the phase transition has rarely been reported. Herein, two novel organic-inorganic hybrid materials, [THPM]n[AgX2]n (THPM = 3,4,5,6-tetrahydropyrimidin-1-ium, X = I for 1 and Br for 2) with the [AgX2]nn- anionic chain structure, were synthesized. At 293 K, the [AgX2]nn- chains in 1 were constructed by the tetramer units of Ag atoms, while that in 2 was assembled by the dimer structure. Upon heating to 355 K, owing to the variation of the metallophilic interaction between adjacent Ag atoms, a unique transformation process from tetramer to dimer in [AgI2]nn- chains of 1 can be detected and endow 1 with a giant anisotropic thermal expansion with linear strain of ∼7% and shear strain of ∼20%, which can be used as a mechanical actuator for switching. Alternatively, for 2, no phase transition process can be observed upon the temperature variation. This work provides an effective approach to design phase transition materials triggered by the inorganic part.

4.
Small Methods ; : e2400323, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940224

RESUMO

The graphene oxide (GO) membrane displays promising potential in efficiently filtering ions from water. However, the precise mechanism behind its effectiveness remains elusive, particularly due to the lack of direct experimental evidence at the atomic scale. To shed light on this matter, state-of-the-art techniques are employed such as integrated differential phase contrast-scanning transmission electron microscopy and electron energy loss spectroscopy, combined with reverse osmosis (RO) filtration experiments using GO membranes. The atomic-scale observations after the RO experiments directly reveal the binding of various ions including Na+, K+, Ca2+, and Fe3+ to the defects, edges, and functional groups of GO. The remarkable ion-sieving capabilities of GO membranes are confirmed, which can be attributed to a synergistic interplay of size exclusion, electrostatic interactions, cation-π, and other non-covalent interactions. Moreover, GO membranes modified by external pressure and cation also demonstrated further enhanced filtration performance for filtration. This study significantly contributes by uncovering the atomic-scale mechanism responsible for ion sieving in GO membranes. These findings not only enhance the fundamental understanding but also hold substantial potential for the advancement of GO membranes in reverse osmosis (RO) filtration.

5.
Small Methods ; : e2400211, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38766949

RESUMO

2D materials are intriguing due to their remarkably thin and flat structure. This unique configuration allows the majority of their constituent atoms to be accessible on the surface, facilitating easier electron tunneling while generating weak surface forces. To decipher the subtle signals inherent in these materials, the application of techniques that offer atomic resolution (horizontal) and sub-Angstrom (z-height vertical) sensitivity is crucial. Scanning probe microscopy (SPM) emerges as the quintessential tool in this regard, owing to its atomic-level spatial precision, ability to detect unitary charges, responsiveness to pico-newton-scale forces, and capability to discern pico-ampere currents. Furthermore, the versatility of SPM to operate under varying environmental conditions, such as different temperatures and in the presence of various gases or liquids, opens up the possibility of studying the stability and reactivity of 2D materials in situ. The characteristic flatness, surface accessibility, ultra-thinness, and weak signal strengths of 2D materials align perfectly with the capabilities of SPM technologies, enabling researchers to uncover the nuanced behaviors and properties of these advanced materials at the nanoscale and even the atomic scale.

6.
Adv Mater ; : e2404278, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743014

RESUMO

Atom-site catalysts, especially for graphitic carbon nitride-based catalysts, represents one of the most promising candidates in catalysis membrane for water decontamination. However, unravelling the intricate relationships between synthesis-structure-properties remains a great challenge. This study addresses the impacts of coordination environment and structure units of metal central sites based on Mantel test, correlation analysis, and evolution of metal central sites. An optimized unconventional oxygen doping cooperated with Co-N-Fe dual-sites (OCN Co/Fe) exhibits synergistic mechanism for efficient peroxymonosulfate activation, which benefits from a significant increase in charge density at the active sites and the regulation in the natural population of orbitals, leading to selective generation of SO4 •-. Building upon these findings, the OCN-Co/Fe/PVDF composite membrane demonstrates a 33 min-1 ciprofloxacin (CIP) rejection efficiency and maintains over 96% CIP removal efficiency (over 24 h) with an average permeance of 130.95 L m-2 h-1. This work offers a fundamental guide for elucidating the definitive origin of catalytic performance in advance oxidation process to facilitate the rational design of separation catalysis membrane with improved performance and enhanced stability.

7.
Angew Chem Int Ed Engl ; 63(27): e202402374, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38655601

RESUMO

The construction of secondary building units (SBUs) in versatile metal-organic frameworks (MOFs) represents a promising method for developing multi-functional materials, especially for improving their sensitizing ability. Herein, we developed a dual small molecules auxiliary strategy to construct a high-nuclear transition-metal-based UiO-architecture Co16-MOF-BDC with visible-light-absorbing capacity. Remarkably, the N3 - molecule in hexadecameric cobalt azide SBU offers novel modification sites to precise bonding of strong visible-light-absorbing chromophores via click reaction. The resulting Bodipy@Co16-MOF-BDC exhibits extremely high performance for oxidative coupling benzylamine (~100 % yield) via both energy and electron transfer processes, which is much superior to that of Co16-MOF-BDC (31.5 %) and Carboxyl @Co16-MOF-BDC (37.5 %). Systematic investigations reveal that the advantages of Bodipy@Co16-MOF-BDC in dual light-absorbing channels, robust bonding between Bodipy/Co16 clusters and efficient electron-hole separation can greatly boost photosynthesis. This work provides an ideal molecular platform for synergy between photosensitizing MOFs and chromophores by constructing high-nuclear transition-metal-based SBUs with surface-modifiable small molecules.

8.
J Ethnopharmacol ; 328: 118109, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38570147

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The Dryopteris crassirhizoma Nakai., a commonly used herb, is known as "Guan Zhong" in China, "Oshida" in Japan and "Gwanjung" in Korea. It has long been used for parasitic infestation, hemorrhages and epidemic influenza. AIM OF THE REVIEW: The present paper aims to provide an up-to-date review at the advancements of the investigations on the traditional use, phytochemistry, pharmacological activity, toxicology and pharmacokinetics of D. crassirhizoma. Besides, possible trends, therapeutic potentials, and perspectives for future research of this plant are also briefly discussed. MATERIALS AND METHODS: Relevant information on traditional use, phytochemistry, pharmacological activity, toxicology and pharmacokinetics of D. crassirhizoma was collected through published materials and electronic databases, including the Chinese Pharmacopoeia, Flora of China, Web of Science, PubMed, Baidu Scholar, Google Scholar, and China National Knowledge Infrastructure. 109 papers included in the article and we determined that no major information was missing after many checks. All authors participated in the review process for this article and all research paper are from authoritative published materials and electronic databases. RESULTS: 130 chemical components, among which phloroglucinols are the predominant groups, have been isolated and identified from D. crassirhizoma. D. crassirhizoma with its bioactive compounds is possessed of extensive biological activities, including anti-parasite, anti-microbial, anti-viral, anti-cancer, anti-inflammatory, anti-oxidant, anti-diabetic, bone protective, immunomodulatory, anti-platelet and anti-hyperuricemia activity. Besides, D. crassirhizoma has special toxicology and pharmacokinetics characterization. CONCLUSIONS: D. crassirhizoma is a traditional Chinese medicine having a long history of application. This review mainly summarized the different chemical components extract from D. crassirhizoma and various reported pharmacological effects. Besides, the toxicology and pharmacokinetics of D. crassirhizoma also be analysed in this review. However, the chemical components of D. crassirhizoma are understudied and require further research to expand its medicinal potential, and it is urgent to design a new extraction scheme, so that the active ingredients can be obtained at a lower cost.


Assuntos
Botânica , Medicamentos de Ervas Chinesas , Dryopteris , Compostos Fitoquímicos/uso terapêutico , Compostos Fitoquímicos/toxicidade , Fitoterapia , Medicina Tradicional Chinesa , Etnofarmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/toxicidade , Extratos Vegetais/uso terapêutico , Extratos Vegetais/toxicidade
9.
ACS Nano ; 18(18): 11573-11597, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38655635

RESUMO

The growth of two-dimensional (2D) materials through chemical vapor deposition (CVD) has sparked a growing interest among both the industrial and academic communities. The interest stems from several key advantages associated with CVD, including high yield, high quality, and high tunability. In order to harness the application potentials of 2D materials, it is often necessary to transfer them from their growth substrates to their desired target substrates. However, conventional transfer methods introduce contamination that can adversely affect the quality and properties of the transferred 2D materials, thus limiting their overall application performance. This review presents a comprehensive summary of the current clean transfer methods for 2D materials with a specific focus on the understanding of interaction between supporting layers and 2D materials. The review encompasses various aspects, including clean transfer methods, post-transfer cleaning techniques, and cleanliness assessment. Furthermore, it analyzes and compares the advances and limitations of these clean transfer techniques. Finally, the review highlights the primary challenges associated with current clean transfer methods and provides an outlook on future prospects.

10.
Shanghai Kou Qiang Yi Xue ; 33(1): 1-5, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38583017

RESUMO

PURPOSE: To elucidate the disparities and similarities in the composition and function of fibroblast subtypes between normal oral mucosa and cutaneous tissue, to establish a unified classification of fibroblast subtypes between these two tissue types, comprehend the differences and similarities in their functionalities, and provide a foundational basis for future applications in the fields of tissue repair and regeneration. METHODS: Four single-cell databases from both oral mucosa and cutaneous tissue were integrated and fibroblast subpopulations were extracted. Batch effects were eliminated using Harmony, and fibroblast subpopulations were subsequently classified via UMAP (Uniform Manifold Approximation and Projection) clustering. The functional analysis of these subpopulations was conducted through gene set enrichment results. Statistical analysis was performed with R 4.2.0 software package. RESULTS: Eight distinct functional fibroblast subpopulations were defined, and their functions were found to be associated with the composition of the extracellular matrix, immunity, and contraction. Statistical analysis revealed differences in the composition ratios of these subpopulations between oral mucosa and skin tissue. CONCLUSIONS: To evaluate the role of fibroblasts in tissue homeostasis and wound healing accomplished by integrating and analyzing fibroblasts from normal skin and oral mucosal tissue from various sites, this study identifies the differences in fibroblast subpopulation composition and function between these two tissue types in healthy conditions, and provides an understanding of oral mucosa and skin homeostasis and cellular function at the transcriptomic level. The findings of this study may serve as a basis for future research in this area.


Assuntos
Mucosa Bucal , Transcriptoma , Cicatrização , Pele , Fibroblastos
11.
J Org Chem ; 89(5): 3390-3402, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38377557

RESUMO

The introduction of alkyne moieties into peptides remains in demand as it represents a promising approach for further structural diversification of peptides. Herein, we describe the Pd(II)-catalyzed C(sp3)-H alkynylation of Ala-Asn-embedded di- and tripeptides using Asn as the endogenous lead group. In addition, a key building block for the glycopeptide Tyc4PG-14 and Tyc4PG-15 was produced by our methodology.


Assuntos
Alanina , Alcinos , Glicopeptídeos , Catálise
12.
J Am Chem Soc ; 146(8): 5414-5422, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38353405

RESUMO

Molecular-based multiferroic materials that possess ferroelectric and ferroelastic orders simultaneously have attracted tremendous attention for their potential applications in multiple-state memory devices, molecular switches, and information storage systems. However, it is still a great challenge to effectively construct novel molecular-based multiferroic materials with multifunctionalities. Generally, the structure of these materials possess high symmetry at high temperatures, while processing an obvious order-disorder or displacement-type ferroelastic or ferroelectric phase transition triggered by symmetry breaking during the cooling processes. Therefore, these materials can only function below the Curie temperature (Tc), the low of which is a severe impediment to their practical application. Despite great efforts to elevate Tc, designing single-phase crystalline materials that exhibit multiferroic orders above room temperature remains a challenge. Here, an inverse temperature symmetry-breaking phenomenon was achieved in [FPM][Fe3(µ3-O)(µ-O2CH)8] (FPM stands for 3-(3-formylamino-propyl)-3,4,5,6-tetrahydropyrimidin-1-ium, which acts as the counterions and the rotor component in the network), enabling a ferroelastoelectric phase at a temperature higher than Tc (365 K). Upon heating from room temperature, two-step distinct symmetry breaking with the mm2Fm species leads to the coexistence of ferroelasticity and ferroelectricity in the temperature interval of 365-426 K. In the first step, the FPM cations undergo a conformational flip-induced inverse temperature symmetry breaking; in the second step, a typical ordered-disordered motion-induced symmetry breaking phase transition can be observed, and the abnormal inverse temperature symmetry breaking is unprecedented. Except for the multistep ferroelectric and ferroelastic switching, this complex also exhibits fascinating nonlinear optical switching properties. These discoveries not only signify an important step in designing novel molecular-based multiferroic materials with high working temperatures, but also inspire their multifunctional applications such as multistep switches.

13.
Heliyon ; 10(3): e25037, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38333825

RESUMO

Objectives: This retrospective cohort study aimed to analyze volumes of craniomaxillofacial bone and masticatory muscles of young adults with bilateral idiopathic condylar resorption. Methods: This was a retrospective cohort study of 84 adults with bilateral idiopathic condylar resorption (BCR) and 48 adults with normal temporal-mandibular joint (TMJ) matched for age and sex (mean age, 23.2 ± 3.6 years). The volumes of craniomaxillofacial bone and masticatory muscles, as well as intercondylar angle were measured. Unpaired t-tests and Pearson correlation tests were applied to analyze the data. Multivariable linear regression models were used to estimate the association between bilateral condylar volume and volumes of craniomaxillofacial bone and masticatory muscles adjusted for age, sex, and disc status. Results: Compared to the control group, the BCR group displayed significant decreased volumes of craniomaxillofacial bone (p < 0.001), craniomaxillofacial bone without mandible (p < 0.001), mandible (p < 0.001), mandible without mandibular condylar process (p < 0.001), bilateral masseter muscle (p < 0.001) and bilateral temporalis muscle (p < 0.001), as well as the intercondylar angle (p < 0.001). These variables were significantly correlated to the volume of mandibular condylar process (0.5< r < 0.8; p < 0.001). By linear regression analyses, significant associations were found for the bilateral condylar volume with craniomaxillofacial bone volume and mandible bone volume. Conclusions: Young adults with BCR displayed smaller volumes of craniomaxillofacial skeleton and masticatory muscles, and smaller intercondylar angle than the normal patients. The craniofacial musculoskeletal volume and intercondylar angle are associated with mandibular condylar process volume.

14.
J Med Chem ; 67(4): 2712-2731, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38295759

RESUMO

The bromodomain and extra-terminal domain (BET) proteins are epigenetic readers, regulating transcription via two highly homologous tandem bromodomains, BD1 and BD2. Clinical development of nonselective pan-BD BET inhibitors has been challenging, partly due to dose-limiting side effects such as thrombocytopenia. This has prompted the push for domain-selective BET inhibitors to achieve a more favorable therapeutic window. We report a structure-guided drug design campaign that led to the development of a potent BD1-selective BET inhibitor, 33 (XL-126), with a Kd of 8.9 nM and 185-fold BD1/BD2 selectivity. The high selectivity was first assayed by SPR, validated by a secondary time-resolved fluorescence energy transfer assay, and further corroborated by BROMOscan (∼57-373 fold selectivity). The cocrystal of 33 with BRD4 BD1 and BD2 demonstrates the source of selectivity: repulsion with His437 and lost binding with the leucine clamp. Notably, the BD1 selectivity of BET inhibitor 33 leads to both the preservation of platelets and potent anti-inflammatory efficacy.


Assuntos
Proteínas Nucleares , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Proteínas Nucleares/metabolismo , Domínios Proteicos , Anti-Inflamatórios/farmacologia , Piridonas/farmacologia , Proteínas de Ciclo Celular/metabolismo
15.
J Craniofac Surg ; 35(1): e28-e31, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38294302

RESUMO

This study aimed to investigate the correlation between mandibular deviation (MD) and possible clinical factors in patients with anterior disc displacement (ADD). This retrospective clinical study enrolled 296 patients with ADD, diagnosed using magnetic resonance imaging, from 2015 to 2018. The clinical symptoms and medical histories of these patients were carefully examined and recorded. Mandibular deviation was the primary outcome variable confirmed by a combination of clinical examination and facial photographs or posteroanterior cephalograms. The primary predictor variable was ADD staging. Secondary predictor variables included condylar height and distance of disc displacement. Other predictor variables were age, sex, disease course, oral parafunctions, depression, and bone mineral density. We used logistic regression to examine the correlation between the MD and all predictor variables. The χ2 test and analysis of variance were used to exclude the correlation between the predictor variables. In this study, the prevalence of MD was 77% among 278 patients with ADD. Bilateral ADD staging significantly contributed to MD on both sides. The odds ratio increased with the deterioration of disc displacement. The present study demonstrated that the ADD staging influences the condylar height and MD, and that articular disk position should be considered while treating MD.


Assuntos
Densidade Óssea , Má Oclusão , Humanos , Estudos Retrospectivos , Progressão da Doença , Face
16.
Nat Mater ; 23(2): 196-204, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38191634

RESUMO

The quest for electronic devices that offer flexibility, wearability, durability and high performance has spotlighted two-dimensional (2D) van der Waals materials as potential next-generation semiconductors. Especially noteworthy is indium selenide, which has demonstrated surprising ultra-high plasticity. To deepen our understanding of this unusual plasticity in 2D van der Waals materials and to explore inorganic plastic semiconductors, we have conducted in-depth experimental and theoretical investigations on metal monochalcogenides (MX) and transition metal dichalcogenides (MX2). We have discovered a general plastic deformation mode in MX, which is facilitated by the synergetic effect of phase transitions, interlayer gliding and micro-cracks. This is in contrast to crystals with strong atomic bonding, such as metals and ceramics, where plasticity is primarily driven by dislocations, twinning or grain boundaries. The enhancement of gliding barriers prevents macroscopic fractures through a pinning effect after changes in stacking order. The discovery of ultra-high plasticity and the phase transition mechanism in 2D MX materials holds significant potential for the design and development of high-performance inorganic plastic semiconductors.

18.
Front Pharmacol ; 14: 1275113, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38094884

RESUMO

Chinese olive is a popular fruit with a long history of cultivation and consumption. As a fruit with edible, nutritional, and even medicinal value, the Chinese olive has attracted increased interest from both nutrition researchers and health-conscious consumers. Chinese olive is a rich nutrient source, including essential and non-essential amino acids, various fatty acids, organic acids, vitamins, microelements, and high-quality dietary fibers. It is also an important natural source of phytochemicals such as phenolic acids, flavonoids, phenylpropanoids, and other bioactive compounds. The nutritional and phytochemical compounds obtained from the Chinese olive exhibit unique and potent biological activities, explaining its various benefits to human health, including anti-Helicobacter pylori, anti-influenza, anti-diabetes, anti-inflammatory, anti-tumor effects, among others. This review focuses on recent studies on Chinese olives and aims to summarize the major advances in their nutritional value, phytochemical composition, health benefits, and practical applications. It provides a reference for further research on Chinese olives and their properties and the development of novel functional products.

19.
Nat Commun ; 14(1): 7304, 2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-37951934

RESUMO

Multiferroic materials have ignited enormous interest owing to their co-existence of ferroelectricity and ferromagnetism, which hold substantial promise for advanced device applications. However, the size effect, dangling bonds, and interface effect in traditional multiferroics severely hinder their potential in nanoscale device applications. Recent theoretical and experimental studies have evidenced the possibility of realizing two-dimensional (2D) multiferroicity in van der Waals (vdW) layered CuCrP2S6. However, the incorporation of magnetic Cr ions in the ferroelectric framework leads to antiferroelectric and antiferromagnetic orderings, while macroscopic spontaneous polarization is always absent. Herein, we report the direct observation of robust out-of-plane ferroelectricity in 2D vdW CuCrP2S6 at room temperature with a comprehensive investigation. Modification of the ferroelectric polarization states in 2D CuCrP2S6 nanoflakes is experimentally demonstrated. Moreover, external electric field-induced polarization switching and hysteresis loops are obtained in CuCrP2S6 down to ~2.6 nm (4 layers). By using atomically resolved scanning transmission electron microscopy, we unveil the origin of the emerged room-temperature ferroelectricity in 2D CuCrP2S6. Our work can facilitate the development of multifunctional nanodevices and provide important insights into the nature of ferroelectric ordering of this 2D vdW material.

20.
Nat Commun ; 14(1): 6462, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37833368

RESUMO

Surface amorphization provides electrocatalysts with more active sites and flexibility. However, there is still a lack of experimental observations and mechanistic explanations for the in situ amorphization process and its crucial role. Herein, we propose the concept that by in situ reconstructed amorphous surface, metal phosphorus trichalcogenides could intrinsically offer better catalytic performance for the alkaline hydrogen production. Trace Ru (0.81 wt.%) is doped into NiPS3 nanosheets for alkaline hydrogen production. Using in situ electrochemical transmission electron microscopy technique, we confirmed the amorphization process occurred on the edges of NiPS3 is critical for achieving superior activity. Comprehensive characterizations and theoretical calculations reveal Ru primarily stabilized at edges of NiPS3 through in situ formed amorphous layer containing bridging S22- species, which can effectively reduce the reaction energy barrier. This work emphasizes the critical role of in situ formed active layer and suggests its potential for optimizing catalytic activities of electrocatalysts.

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