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1.
Adv Mater ; : e2400640, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621196

RESUMO

Nowadays, high-valent Cu species (i.e., Cuδ +) are clarified to enhance multi-carbon production in electrochemical CO2 reduction reaction (CO2RR). Nonetheless, the inconsistent average Cu valence states are reported to significantly govern the product profile of CO2RR, which may lead to misunderstanding of the enhanced mechanism for multi-carbon production and results in ambiguous roles of high-valent Cu species. Dynamic Cuδ + during CO2RR leads to erratic valence states and challenges of high-valent species determination. Herein, an alternative descriptor of (sub)surface oxygen, the (sub)surface-oxygenated degree (κ), is proposed to quantify the active high-valent Cu species on the (sub)surface, which regulates the multi-carbon production of CO2RR. The κ validates a strong correlation to the carbonyl (*CO) coupling efficiency and is the critical factor for the multi-carbon enhancement, in which an optimized Cu2O@Pd2.31 achieves the multi-carbon partial current density of ≈330 mA cm-2 with a faradaic efficiency of 83.5%. This work shows a promising way to unveil the role of high-valent species and further achieve carbon neutralization.

2.
Biomedicines ; 12(4)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38672136

RESUMO

Inflammatory bowel disease (IBD) is an inflammatory condition affecting the colon and small intestine, with Crohn's disease and ulcerative colitis being the major types. Individuals with long-term IBD are at an increased risk of developing colorectal cancer. Early growth response protein 1 (Egr1) is a nuclear protein that functions as a transcriptional regulator. Egr1 is known to control the expression of numerous genes and play a role in cell growth, proliferation, and differentiation. While IBD has been associated with severe inflammation, the precise mechanisms underlying its pathogenesis remain unclear. This study aimed to investigate the role of Egr1 in the development of IBD. High levels of Egr1 expression were observed in a mouse model of colitis induced by dextran sulfate sodium (DSS), as determined by immunohistochemical (IHC) staining. Chronic DSS treatment showed that Egr1 knockout (KO) mice exhibited resistance to the development of IBD, as determined by changes in their body weight and disease scores. Additionally, enzyme-linked immunosorbent assay (ELISA) and IHC staining demonstrated decreased expression levels of proinflammatory cytokines such as IL-1ß, IL-6, and TNF-α, as well as matrix metalloproteinase 12 (MMP12). Putative Egr1 binding sites were identified within the MMP12 promoter region. Through reporter assays and chromatin immunoprecipitation (ChIP) analysis, it was shown that Egr1 binds to the MMP12 promoter and regulates MMP12 expression. In conclusion, we found that Egr1 plays a role in the inflammation process of IBD through transcriptionally activating MMP12.

3.
Adv Mater ; 36(14): e2313548, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38279631

RESUMO

Electrocatalytic nitrate reduction reaction (NO3RR) toward ammonia synthesis is recognized as a sustainable strategy to balance the global nitrogen cycle. However, it still remains a great challenge to achieve highly efficient ammonia production due to the complex proton-coupled electron transfer process in NO3RR. Here, the controlled synthesis of RuMo alloy nanoflowers (NFs) with unconventional face-centered cubic (fcc) phase and hexagonal close-packed/fcc heterophase for highly efficient NO3RR is reported. Significantly, fcc RuMo NFs demonstrate high Faradaic efficiency of 95.2% and a large yield rate of 32.7 mg h-1 mgcat -1 toward ammonia production at 0 and -0.1 V (vs reversible hydrogen electrode), respectively. In situ characterizations and theoretical calculations have unraveled that fcc RuMo NFs possess the highest d-band center with superior electroactivity, which originates from the strong Ru─Mo interactions and the high intrinsic activity of the unconventional fcc phase. The optimal electronic structures of fcc RuMo NFs supply strong adsorption of key intermediates with suppression of the competitive hydrogen evolution, which further determines the remarkable NO3RR performance. The successful demonstration of high-performance zinc-nitrate batteries with fcc RuMo NFs suggests their substantial application potential in electrochemical energy supply systems.

4.
J Am Chem Soc ; 145(49): 27054-27066, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38040669

RESUMO

Single-atom catalysts (SACs) featuring M-N-C moieties have garnered significant attention as efficient electrocatalysts for the oxygen reduction reaction (ORR). However, the role of the dynamic M-N configuration of SACs induced by the derived frameworks under applied ORR potentials remains poorly understood. Herein, we conduct a comprehensive investigation using multiple operando techniques to assess the dynamic configurations of Cu SACs under various microstructural interface (MSI) regulations by anchoring atomic Cu on g-C3N4 and zeolitic imidazolate framework (ZIF) substrates. Cu SACs supported on g-C3N4 exhibit symmetric Cu-N configurations characterized by a reversibly adaptive nature under operational conditions, which leads to their excellent ORR catalytic activity. In contrast, the Cu-N configuration in ZIF-derived Cu SACs undergoes irreversible structural changes during the ORR process, in which the elongated Cu-N pair is unstable and breaks during the ORR, acting as a competing reaction against the ORR and resulting in high overpotential requirements. Crucially, operando time-resolved X-ray absorption spectroscopy (TR-XAS) and Raman results unequivocally reveal the reversibly adapting properties of the local Cu-N configuration in atomic Cu-anchored g-C3N4, which have been overlooked in numerous literatures. All findings provide valuable insights into the potential-driven characteristics of atomic electrocatalysts during target reactions and offer a systematic approach to study atomic electrocatalysts and their corresponding catalytic behaviors.

5.
Nat Commun ; 14(1): 6576, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37852958

RESUMO

Realizing viable electrocatalytic processes for energy conversion/storage strongly relies on an atomic-level understanding of dynamic configurations on catalyst-electrolyte interface. X-ray absorption spectroscopy (XAS) has become an indispensable tool to in situ investigate dynamic natures of electrocatalysts but still suffers from limited energy resolution, leading to significant electronic transitions poorly resolved. Herein, we highlight advanced X-ray spectroscopies beyond conventional XAS, with emphasis on their unprecedented capabilities of deciphering key configurations of electrocatalysts. The profound complementarities of X-ray spectroscopies from various aspects are established in a probing energy-dependent "in situ spectroscopy map" for comprehensively understanding the solid-liquid interface. This perspective establishes an indispensable in situ research model for future studies and offers exciting research prospects for scientists and spectroscopists.

6.
Nat Commun ; 14(1): 5245, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37640719

RESUMO

One challenge for realizing high-efficiency electrocatalysts for CO2 electroreduction is lacking in comprehensive understanding of potential-driven chemical state and dynamic atomic-configuration evolutions. Herein, by using a complementary combination of in situ/operando methods and employing copper single-atom electrocatalyst as a model system, we provide evidence on how the complex interplay among dynamic atomic-configuration, chemical state change and surface coulombic charging determines the resulting product profiles. We further demonstrate an informative indicator of atomic surface charge (φe) for evaluating the CO2RR performance, and validate potential-driven dynamic low-coordinated Cu centers for performing significantly high selectivity and activity toward CO product over the well-known four N-coordinated counterparts. It indicates that the structural reconstruction only involved the dynamic breaking of Cu-N bond is partially reversible, whereas Cu-Cu bond formation is clearly irreversible. For all single-atom electrocatalysts (Cu, Fe and Co), the φe value for efficient CO production has been revealed closely correlated with the configuration transformation to generate dynamic low-coordinated configuration. A universal explication can be concluded that the dynamic low-coordinated configuration is the active form to efficiently catalyze CO2-to-CO conversion.

7.
J Am Chem Soc ; 145(32): 17892-17901, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37482661

RESUMO

Exploring an efficient and robust electrocatalyst for hydrogen evolution reaction (HER) at high pH and temperature holds the key to the industrial application of alkaline water electrolysis (AWE). Herein, we design an open tunnel structure by dealloying a series of Laves phase intermetallics, i.e., MCo2 and MRu0.25Co1.75 (M = Sc and Zr). The dealloying process can induce a zeolite-like metal framework for ScCo2 and ScRu0.25Co1.75 by stripping Sc metal from the center of a tunnel structure. This structural engineering significantly lowers their overpotentials at a current density of 500 mA/cm2 (η500) ca. 80 mV in 1.0 M KOH. Through a simple process, ScRu0.25Co1.75 can be easily decorated on a carbon cloth substrate and only requires 132 mV to reach 500 mA/cm2. More importantly it can maintain activity over 1000 h in industrial conditions (6.0 M KOH at 333 K), showing its potential for practical industrial applications.

8.
Chem Soc Rev ; 52(15): 5013-5050, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37431250

RESUMO

The ubiquity of solid-liquid interfaces in nature and the significant role of their atomic-scale structure in determining interfacial properties have led to intensive research. Particularly in electrocatalysis, however, a molecular-level picture that clearly describes the dynamic interfacial structures and organizations with their correlation to preferred reaction pathways in electrochemical reactions remains poorly understood. In this review, CO2 electroreduction reaction (CO2RR) is spatially and temporally understood as a result of intricate interactions at the interface, in which the interfacial features are highly relevant. We start with the discussion of current understandings and model development associated with the charged electrochemical interface as well as its dynamic landscape. We further highlight the interactive dynamics from the interfacial field, catalyst surface charges and various gradients in electrolyte and interfacial water structures at interfaces under CO2RR working conditions, with emphasis on the interfacial-structure dependence of catalytic reactivity/selectivity. Significantly, a probing energy-dependent "in situ characterization map" for dynamic interfaces based on various complementary in situ/operando techniques is proposed, aiming to present a comprehensive picture of interfacial electrocatalysis and to provide a more unified research framework. Moreover, recent milestones in both experimental and theoretical aspects to establish the correct profile of electrochemical interfaces are stressed. Finally, we present key scientific challenges with related perspectives toward future opportunities for this exciting frontier.

9.
Adv Mater ; 35(35): e2301133, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37029606

RESUMO

Guaranteeing satisfactory catalytic behavior while ensuring high metal utilization has become the problem that needs to be addressed when designing noble-metal-based catalysts for electrochemical reactions. Here, well-dispersed ruthenium (Ru) based clusters with adjacent Ru single atoms (SAs) on layered sodium cobalt oxide (Ru/NC) are demonstrated as a superb electrocatalyst for alkaline HER. The Ru/NC catalyst demonstrates an activity increase by a factor of two relative to the commercial Pt/C. Operando characterizations in conjunction with density functional theory (DFT) simulations uncover the origin of the superior activity and establish a structure-performance relationship, that is, under HER condition, the real active species are Ru SAs and metallic Ru clusters supported on the NC substrate. The excellent alkaline HER activity of the Ru/NC catalyst can be understood by a spatially decoupled water dissociation and hydrogen desorption mechanism, where the NC substrate accelerates the water dissociation rate, and the generated H intermediates would then migrate to the Ru SAs or clusters and recombine to have H2 evolution. More importantly, comparing the two forms of Ru sites, it is the Ru cluster that dominates the HER activity.

10.
Small ; 19(34): e2301711, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37093181

RESUMO

Solar-driven CO2 conversion into valuable fuels is a promising strategy to alleviate the energy and environmental issues. However, inefficient charge separation and transfer greatly limits the photocatalytic CO2 reduction efficiency. Herein, single-atom Pt anchored on 3D hierarchical TiO2 -Ti3 C2 with atomic-scale interface engineering is successfully synthesized through an in situ transformation and photoreduction method. The in situ growth of TiO2 on Ti3 C2 nanosheets can not only provide interfacial driving force for the charge transport, but also create an atomic-level charge transfer channel for directional electron migration. Moreover, the single-atom Pt anchored on TiO2 or Ti3 C2 can effectively capture the photogenerated electrons through the atomic interfacial PtO bond with shortened charge migration distance, and simultaneously serve as active sites for CO2 adsorption and activation. Benefiting from the synergistic effect of the atomic interface engineering of single-atom Pt and interfacial TiOTi, the optimized photocatalyst exhibits excellent CO2 -to-CO conversion activity of 20.5 µmol g-1  h-1 with a selectivity of 96%, which is five times that of commercial TiO2 (P25). This work sheds new light on designing ideal atomic-scale interface and single-atom catalysts for efficient solar fuel conversation.

11.
J Am Chem Soc ; 145(12): 6953-6965, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36921031

RESUMO

Copper-oxide electrocatalysts have been demonstrated to effectively perform the electrochemical CO2 reduction reaction (CO2RR) toward C2+ products, yet preserving the reactive high-valent CuOx has remained elusive. Herein, we demonstrate a model system of Lewis acidic supported Cu electrocatalyst with a pulsed electroreduction method to achieve enhanced performance for C2+ products, in which an optimized electrocatalyst could reach ∼76% Faradaic efficiency for C2+ products (FEC2+) at ∼-0.99 V versus reversible hydrogen electrode, and the corresponding mass activity can be enhanced by ∼2 times as compared to that of conventional CuOx. In situ time-resolved X-ray absorption spectroscopy investigating the dynamic chemical/physical nature of Cu during CO2RR discloses that an activation process induced by the KOH electrolyte during pulsed electroreduction greatly enriched the Cuδ+O/Znδ+O interfaces, which further reveals that the presence of Znδ+O species under the cathodic potential could effectively serve as a Lewis acidic support for preserving the Cuδ+O species to facilitate the formation of C2+ products, and the catalyst structure-property relationship of Cuδ+O/Znδ+O interfaces can be evidently realized. More importantly, we find a universality of stabilizing Cuδ+O species for various metal oxide supports and to provide a general concept of appropriate electrocatalyst-Lewis acidic support interaction for promoting C2+ products.

12.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(11): 1207-1212, 2022 Nov 15.
Artigo em Chinês | MEDLINE | ID: mdl-36398545

RESUMO

OBJECTIVES: To investigate the efficacy of intravitreal anti-vascular endothelial growth factor (anti-VEGF) injection in the treatment of retinopathy of prematurity (ROP) and the risk factors for recurrence. METHODS: A retrospective analysis was performed on the medical data of 159 infants with ROP who were born in the First Affiliated Hospital of Zhengzhou University and underwent anti-VEGF treatment from January 2016 to December 2021. According to the presence or absence of recurrence within the follow-up period after initial anti-VEGF treatment, they were divided into a recurrence group with 24 infants and a non-recurrence group with 135 infants. The medical data were compared between the two groups, and a multivariate logistic regression analysis was used to investigate the risk factors for the recurrence of ROP after anti-VEGF treatment. RESULTS: After one-time anti-VEGF treatment, all 159 infants showed regression of plus disease. Recurrence was observed in 24 infants (15.1%) after anti-VEGF treatment, with a mean interval of (8.4±2.6) weeks from treatment to recurrence. The multivariate logistic regression analysis showed that preoperative fundus hemorrhage and prolonged total oxygen supply time were risk factors for the recurrence of ROP (P<0.05), while gestational hypertension was a protective factor (P<0.05). CONCLUSIONS: Intravitreal anti-VEGF injection is effective for ROP. Preoperative fundus hemorrhage and long duration of oxygen therapy may increase the risk of ROP recurrence, and further studies are needed to investigate the influence of gestational hypertension on the recurrence of ROP.


Assuntos
Hipertensão Induzida pela Gravidez , Retinopatia da Prematuridade , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Inibidores da Angiogênese/efeitos adversos , Inibidores da Angiogênese/uso terapêutico , Fatores de Crescimento Endotelial/uso terapêutico , Hemorragia , Oxigênio/uso terapêutico , Retinopatia da Prematuridade/tratamento farmacológico , Estudos Retrospectivos , Fatores de Risco , Fator A de Crescimento do Endotélio Vascular
13.
Nat Commun ; 13(1): 6650, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333330

RESUMO

Unraveling the precise location and nature of active sites is of paramount significance for the understanding of the catalytic mechanism and the rational design of efficient electrocatalysts. Here, we use well-defined crystalline cobalt oxyhydroxides CoOOH nanorods and nanosheets as model catalysts to investigate the geometric catalytic active sites. The morphology-dependent analysis reveals a ~50 times higher specific activity of CoOOH nanorods than that of CoOOH nanosheets. Furthermore, we disclose a linear correlation of catalytic activities with their lateral surface areas, suggesting that the active sites are exclusively located at lateral facets rather than basal facets. Theoretical calculations show that the coordinatively unsaturated cobalt sites of lateral facets upshift the O 2p-band center closer to the Fermi level, thereby enhancing the covalency of Co-O bonds to yield the reactivity. This work elucidates the geometrical catalytic active sites and enlightens the design strategy of surface engineering for efficient OER catalysts.

14.
Angew Chem Int Ed Engl ; 61(48): e202211142, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36173929

RESUMO

The hetero-atomic interaction has been the subject of many investigations, due to their heterogeneity, the individual roles of the atoms are still difficult to realize. Herein, an electrocatalyst with a hetero-atomic pair confined on a tungsten phosphide (WP) substrate so that the Fe3+ -site of the pair is distal to the surface is shown to deliver an extremely low overpotential of 192 mV at 10 mA cm-2 and one of the highest oxygen production turnover frequencies (TOF) of 2.1 s-1 at 300 mV under alkaline environment for the oxygen evolution reaction (OER). Operando characterization shows the Lewis acidic Fe3+ site boosts a large population of Co4+/3+ and the deprotonation of coordinated water, allowing simultaneously enhanced electron-transfer as well as the proton-transfer. A significant contribution from the WP substrate modulates the order of hydroxide transfer in the pre-equilibrium step (PES) and rate-determining-step (RDS), leading to a remarkable OER performance.

15.
Nanoscale ; 14(25): 8944-8950, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35713505

RESUMO

Unravelling the dynamic characterization of electrocatalysts during the electrochemical CO2 reduction reaction (CO2RR) is a critical factor to improve the production efficiency and selectivity, since most pre-electrocatalysts undergo structural reconstruction and surface rearrangement under working conditions. Herein, a series of pre-electrocatalysts including CuO, ZnO and two different ratios of CuO/ZnO were systematically designed by a sputtering process to clarify the correlation of the dynamic characterization of Cu sites in the presence of Zn/ZnO and the product profile. The evidence provided by in situ X-ray absorption spectroscopy (XAS) indicated that appropriate Zn/ZnO levels could induce a variation in the coordination number of Cu sites via reversing Ostwald ripening. Specifically, the recrystallized Cu site with a lower coordination number exhibited a preferential production of methane (CH4). More importantly, our findings provide a promising approach for the efficient production of CH4 by in situ reconstructing Cu-based binary electrocatalysts.

16.
Adv Mater ; 34(29): e2203621, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35606157

RESUMO

A coupling catalyst of highly dispersed N, P co-doped carbon frames (NPCFs) anchored with Fe single atoms (SAs) and Fe2 P nanoparticles (NPs) is synthesized by a novel in situ doping-adsorption-phosphatization strategy for the electrocatalytic oxygen reduction reaction (ORR). The optimized Fe SAs-Fe2 P NPs/NPCFs-2.5 catalyst shows a superior ORR activity and stability in 0.5 m H2 SO4 and 0.1 m KOH, respectively. Theoretical calculations reveal a synergistic effect, in that the existence of Fe2 P weakens the adsorption of ORR intermediates on active sites and lowers the reaction free energy. The doped P atoms with a strong electron-donating ability elevate the energy level of Fe-3d orbitals and facilitate the adsorption of O2 . The active Fe atoms exist in a low oxidation state and are less positively charged, and they serve as an electron reservoir capable of donating and releasing electrons, thus improving the ORR activity. Operando and in situ characterization results indicate that the atomically dispersed FeN4 /FeP coupled active centers in the Fe SAs-Fe2 P NPs/NPCFs-2.5 catalyst are characteristic of the different catalytic mechanisms in acidic and alkaline media. This work proposes a novel idea for constructing coupling catalysts with atomic-level precision and provides a strong reference for the development of high-efficiency ORR electrocatalysts for practical application.

17.
Artigo em Inglês | MEDLINE | ID: mdl-35156793

RESUMO

Utilizing renewable electricity energy to convert CO2 into fuels and chemicals, namely, CO2 electrocatalytic reduction reaction (CO2RR), is becoming increasingly significant yet challenged by low activity and selectivity. Recently, a growing number of studies have demonstrated that oxidized species can surprisingly survive on the catalyst surface under highly cathodic CO2RR conditions and play crucial roles in affecting the product selectivity. However, dynamic evolutions of the surface chemical state together with its real correlation to the product selectivity are still unclear, which is one of the most controversial topics for CO2RR. Herein, we particularly resurvey recent CO2RR researches that are all based on advanced in situ/operando methodologies, aiming to clearly reveal the realistic variations in surface chemical state under the working conditions. Then, recent progress in the regulation of the surface chemical state toward specific CO2RR products in current state-of-the-art catalysts with varying metal centers is systematically summarized, which shows an impressive relation between the dynamic chemical state and product profile. Next, we further highlight the developed strategies to regulate the surface chemical state in catalysts and discuss the debates over the effects of chemical state on product profile during CO2RR. Finally, on the basis of previous achievements, we present major challenges and some perspectives for the exploration of the imperative chemical state sensitivity to product profile during CO2RR.

18.
J Am Chem Soc ; 144(8): 3386-3397, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35167259

RESUMO

Solar-driven photocatalytic reactions can mildly activate hydrocarbon C-H bonds to produce value-added chemicals. However, the inefficient utilization of photogenerated carriers hinders the application. Here, we report reversible photochromic BiOBr (denoted as p-BiOBr) nanosheets that were colored by trapping photogenerated holes upon visible light irradiation and bleached by water oxidation to generate hydroxyl radicals, demonstrating enhanced carrier separation and water oxidation. The photocatalytic coupling and oxidation reactions of ethylbenzene were efficiently realized by p-BiOBr in a water-based medium under ambient temperature and pressure (apparent quantum yield is 14 times that of pristine BiOBr). The p-BiOBr nanosheets feature lattice disordered defects on the surface, providing rich uncoordinated catalytic sites and inducing structural distortions and lattice strain, which further leads to an altered band structure and significantly enhanced photocatalytic performances. These hole-trapping materials open up the possibility of substantially elevating the utilization efficiency of photogenerated holes for high-efficiency photocatalytic activation of various saturated C-H bonds.

19.
Chem Commun (Camb) ; 58(15): 2524-2527, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35098285

RESUMO

The roles of unforgiving H2SO4 solvent in CH4 activation with molecular catalysts have not been experimentally well-illustrated despite computational predictions. Here, we provide experimental evidence that metal-bound bisulfate ligand introduced by H2SO4 solvent is redox-active in vanadium-based electrocatalytic CH4 activation discovered recently. Replacing one of the two terminal bisulfate ligands with redox-inert dihydrogen phosphate in the pre-catalyst vanadium (V)-oxo dimer completely quenches its activity towards CH4, which may inspire environmentally benign catalysis with minimal use of H2SO4.

20.
J Am Chem Soc ; 144(3): 1174-1186, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-34935380

RESUMO

Real bifunctional electrocatalysts for hydrogen evolution reaction and oxygen evolution reaction have to be the ones that exhibit a steady configuration during/after reaction without irreversible structural transformation or surface reconstruction. Otherwise, they can be termed as "precatalysts" rather than real catalysts. Herein, through a strongly atomic metal-support interaction, single-atom dispersed catalysts decorating atomically dispersed Ru onto a nickel-vanadium layered double hydroxide (LDH) scaffold can exhibit excellent HER and OER activities. Both in situ X-ray absorption spectroscopy and operando Raman spectroscopic investigation clarify that the presence of atomic Ru on the surface of nickel-vanadium LDH is playing an imperative role in stabilizing the dangling bond-rich surface and further leads to a reconstruction-free surface. Through strong metal-support interaction provided by nickel-vanadium LDH, the significant interplay can stabilize the reactive atomic Ru site to reach a small fluctuation in oxidation state toward cathodic HER without reconstruction, while the atomic Ru site can stabilize the Ni site to have a greater structural tolerance toward both the bond constriction and structural distortion caused by oxidizing the Ni site during anodic OER and boost the oxidation state increase in the Ni site that contributes to its superior OER performance. Unlike numerous bifunctional catalysts that have suffered from the structural reconstruction/transformation for adapting the HER/OER cycles, the proposed Ru/Ni3V-LDH is characteristic of steady dual reactive sites with the presence of a strong metal-support interaction (i.e., Ru and Ni sites) for individual catalysis in water splitting and is revealed to be termed as a real bifunctional electrocatalyst.

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