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1.
Small ; 20(24): e2309647, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38240559

RESUMO

1T-MoSe2 is recognized as a promising anode material for sodium-ion batteries, thanks to its excellent electrical conductivity and large interlayer distance. However, its inherent thermodynamic instability often presents unparalleled challenges in phase control and stabilization. Here, a molecular intercalation strategy is developed to synthesize thermally stable 1T-rich MoSe2, covalently bonded to an intercalated carbon layer (1TR/2H-MoSe2@C). Density functional theory calculations uncover that the introduced ethylene glycol molecules not only serve as electron donors, inducing a reorganization of Mo 4d orbitals, but also as sacrificial guest materials that generate a conductive carbon layer. Furthermore, the C─Se/C─O─Mo bonds encourage strong interfacial electronic coupling, and the carbon layer prevents the restacking of MoSe2, regulating the maximum 1T phase to an impressive 80.3%. Consequently, the 1TR/2H-MoSe2@C exhibits an extraordinary rate capacity of 326 mAh g-1 at 5 A g-1 and maintains a long-term cycle stability up to 1500 cycles, with a capacity of 365 mAh g-1 at 2 A g-1. Additionally, the full cell delivers an appealing energy output of 194 Wh kg-1 at 208 W kg-1, with a capacity retention of 87.3% over 200 cycles. These findings contribute valuable insights toward the development of innovative transition metal dichalcogenides for next-generation energy storage technologies.

2.
Small ; 20(5): e2305964, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37759425

RESUMO

Hosts hold great prospects for addressing the dendrite growth and volume expansion of the Li metal anode, but Li dendrites are still observable under the conditions of high deposition capacity and/or high current density. Herein, a nitrogen-doped graphene mesh (NGM) is developed, which possesses a conductive and lithiophilic scaffold for efficient Li deposition. The abundant nanopores in NGM can not only provide sufficient room for Li deposition, but also speed up Li ion transport to achieve a high-rate capability. Moreover, the evenly distributed N dopants on the NGM can guide the uniform nucleation of Li so that to inhibit dendrite growth. As a result, the composite NGM@Li anode shows satisfactory electrochemical performances for Li-S batteries, including a high capacity of 600 mAh g-1 after 300 cycles at 1 C and a rate capacity of 438 mAh g-1 at 3 C. This work provides a new avenue for the fabrication of graphene-based hosts with large areal capacity and high-rate capability for Li metal batteries.

3.
Nano Lett ; 22(9): 3728-3736, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35482551

RESUMO

Electrocatalysts are considered the most promising candidates in ameliorating the slow kinetics of Li-S batteries (LSBs), however, the issue of insufficient catalytic capability remains to be addressed. Herein, we report an integrated catalytic network comprising graphitic carbon-encapsulated/bridged ultrafine NiCoP embedded in N, P-codoped carbon (GC-uNiCoP@NPC) as a highly competent catalyst for sulfur-based species conversions. By profiling the evolution map of Li-S chemistry via operando kinetic analyses, GC-uNiCoP@NPC is demonstrated to possess versatile yet efficient catalytic activity for sulfur reduction/evolution reactions, especially the rate-determining heterogeneous phase transitions. As a result, GC-uNiCoP@NPC enables high capacity and stable cycling of sulfur cathode under high areal loading and lean electrolyte. Moreover, pouch cells assembled under practical conditions present promising performance with a specific energy of 302 Wh kg-1. This work not only conceptually expands the catalyst design for LSBs but also provides a comprehensive insight into the catalyst performance for Li-S chemistry.

4.
Small ; : e1801068, 2018 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-29966041

RESUMO

Herein, a surfactant- and additive-free strategy is developed for morphology-controllable synthesis of cobalt pyrophosphate (CoPPi) nanostructures by tuning the concentration and ratio of the precursor solutions of Na4 P2 O7 and Co(CH3 COO)2 . A series of CoPPi nanostructures including nanowires, nanobelts, nanoleaves, and nanorhombuses are prepared and exhibit very promising electrocatalytic properties toward the oxygen evolution reaction (OER). Acting as both reactant and pseudo-surfactant, the existence of excess Na4 P2 O7 is essential to synthesize CoPPi nanostructures for unique morphologies. Among all CoPPi nanostructures, the CoPPi nanowires catalyst renders the best catalytic performance for OER in alkaline media, achieving a low Tafel slope of 54.1 mV dec-1 , a small overpotential of 359 mV at 10 mA cm-2 , and superior stability. The electrocatalytic activities of CoPPi nanowires outperform the most reported non-noble metal based catalysts, even better than the benchmark Ir/C (20%) catalyst. The reported synthesis of CoPPi gives guidance for morphology control of transition metal pyrophosphate based nanostructures for a high-performance inexpensive material to replace the noble metal-based OER catalysts.

5.
Zhongguo Zhong Yao Za Zhi ; 40(5): 938-45, 2015 Mar.
Artigo em Zh | MEDLINE | ID: mdl-26087560

RESUMO

OBJECTIVE: To investigate the effect of compound Coptidis Rhizoma capsule (CCRC) on unbalanced expression of renal tissue TGF-ß1/BMP-7 and Smad signaling pathway in rats with early diabetic nephropathy (DN), and discuss CCRC's effect on DN rats with early diabetic nephropathy and its possible mechanism. METHOD: DN model rats were established by injecting streptozotocin (STZ). The rats were randomly divided into seven groups: the normal group, the model group, the enalapril treatment group, the xiaoke pill treatment group and three CRCC treatment groups. They were orally administered once a day for five weeks. The fasting blood glucose (FBG), blood urea nitrogen (BUN), serum creatinine (Scr), insulin (Ins), 24 h urinary protein (24 h Upro) and 24 h urinary microalbumin (24 h UmAlb) were tested. The pathological changes in renal tissues were examined by optical microscopy. Immuno- histochemical measures were used to detect the expressions of TGF-ß1, BMP-7, Smad2/3, Smad1/5, and Smad7 protein, and RT-PCR was used to detect TGF-ß1 mRNA and BMP-7 mRNA in renal tissues. RESULT: Compared with model group, BUN, Scr, Ins, 24 h Upro and 24 h UmAlb levels decreased at different degrees in CCRC treatment groups; the abnormal pathomorphology in renal tissue was improved; immunohistochemistry results showed that the expression of TGF-ß1 and Smad2/3 were reduced, while the expression of BMP-7, Smad1/5 and Smad7 increased in CRCC treatment groups; the expression of TGF-ß1 mRNA were reduced, but the expression of BMP-7 mRNA had no obvious change in CRCC treatment groups. CONCLUSION: CRCC can improve the early renal function, delay the progression of chronic renal pathology and maintain the dynamic balance of TGF-ß1/BMP-7 expression in renal tissues of DN rats. The mechanism may be related to down-regulation of renal TGF-ß1 and up-regulation of BMP-7 through Smad signaling pathway.


Assuntos
Proteína Morfogenética Óssea 7/metabolismo , Coptis/química , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Rim/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Proteína Morfogenética Óssea 7/genética , Nefropatias Diabéticas/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Rim/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Rizoma/química , Proteínas Smad/genética
6.
Phys Chem Chem Phys ; 16(32): 16909-13, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-25018099

RESUMO

For the first time we demonstrate the topotactic synthesis of a three-dimensional (3D) interconnected network of nanoporous CoP nanowires directly on a Ti substrate (np-CoP NWs/Ti) via low-temperature phosphidation of a Co2(OH)2(CO3)2/Ti precursor and its further use as a highly efficient hydrogen evolution cathode.

7.
PLoS One ; 19(5): e0302810, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38713685

RESUMO

OBJECTIVE: The two commonly used diagnostic methods for taurodontism are susceptible to aging changes, mastication wear and other factors. Therefore, this study proposed an improved diagnostic method for taurodontism, and compared it with the previous two methods as a supplement for taurodontism diagnosis. METHODS: The included patients were aged 10-89 years and admitted to the Department of Stomatology of Hebei Eye Hospital from June 1, 2022 to May 31, 2023. Eighty cone-beam computed tomography images were divided equally into 4 groups: 10-29, 30-49, 50-69, and 70-89 years old. The right mandibular first molars were selected as measurement objects. Firstly, |BD| and taurodontism index (TI)-related parameters were measured using Shifman and Chanannel's method and crown-body(CB) and root (R) lengths was measured by Seow and Lai's method. The improved method used the length from the cementoenamel junction(CEJ) to the root bifurcation point(body, B)and the root length(root, R)as the measurement objects. Finally, TI, CB/R ratios, and B/R ratios were calculated according to the formulas given below. One-way ANOVA analysis was mainly used to compare the differences in the values, indices and ratios of taurodontism among different age groups (p<0.05). RESULTS: With the increase of age, |BD| and TI values decreased significantly (p<0.01). The CB/R ratios of 70-89 years group were significantly lower than those of the other three groups (p<0.01). Ratios derived from the improved method were significantly lower in the 70-89 years than in 10-29 years group (p<0.05). CONCLUSIONS: The |BD| and TI parameters proposed by Shifman and channel are significantly influenced by age. The measurements of Seow and Lai (CB/R ratios) were less affected by age compared with those of the former. The improved method(B/R ratios) was least affected by age, which would reduce error and bias in the measurement of taurodontism and obtain more objective results in older patients.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Cavidade Pulpar/anormalidades , Humanos , Idoso , Pessoa de Meia-Idade , Adolescente , Adulto , Idoso de 80 Anos ou mais , Criança , Feminino , Masculino , Adulto Jovem , Tomografia Computadorizada de Feixe Cônico/métodos , Dente Molar/diagnóstico por imagem , Anormalidades Dentárias/diagnóstico por imagem , Anormalidades Dentárias/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico
8.
ChemSusChem ; : e202400705, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38818626

RESUMO

The vanadium redox flow battery (VRFB) holds promise for large-scale energy storage applications, despite its lower energy and power densities compared to advanced secondary batteries available today. Carbon materials are considered suitable catalyst electrodes for improving many aspects of the VRFB. However, pristine graphite structures in carbon materials are catalytically inert and require modification to activate their catalytic activity. Among the various strategies developed so far, O-functionalization and chemical doping of carbon materials are considered some of the most promising pathways to regulate their electronic structures. Building on the catalytic mechanisms involved in the VRFB, this concise review discusses recent advancements in the O-functionalization and chemical doping of carbon materials. Furthermore, it explores how these materials can be tailored and highlights future directions for developing more promising VRFBs to guide future research.

9.
Chem Commun (Camb) ; 60(19): 2649-2652, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38348769

RESUMO

LiNO3 is recognized as an effective additive, forming a dense, nitrogen-rich solid electrolyte interphase (SEI) on lithium's surface, which safeguards it from parasitic reactions. However, its use is limited due to the poor solubility in carbonate electrolytes. Herein, we introduce a bilayer separator designed to release LiNO3 sustainably. This continual release not only alters the chemistry of the SEI but also replenishes the additives that are depleted during battery cycling, thereby enhancing the durability of the modified interphase. This strategy effectively curtails Li dendrite formation, significantly enhancing the longevity of Li|LiFePO4 batteries, evidenced by an impressive 85% capacity retention after 800 cycles. This research offers a compelling remedy to the longstanding challenge of incorporating LiNO3 in carbonate electrolytes.

10.
Adv Mater ; 35(16): e2210734, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36623267

RESUMO

Graphene has long been recognized as a potential anode for next-generation lithium-ion batteries (LIBs). The past decade has witnessed the rapid advancement of graphene anodes, and considerable breakthroughs are achieved so far. In this review, the aim is to provide a research roadmap of graphene anodes toward practical LIBs. The Li storage mechanism of graphene is started with and then the approaches to improve its electrochemical performance are comprehensively summarized. First, morphologically engineered graphene anodes with porous, spheric, ribboned, defective and holey structures display improved capacity and rate performance owing to their highly accessible surface area, interconnected diffusion channels, and sufficient active sites. Surface-modified graphene anodes with less aggregation, fast electrons/ions transportation, and optimal solid electrolyte interphase are discussed, demonstrating the close connection between the surface structure and electrochemical activity of graphene. Second, graphene derivatives anodes prepared by heteroatom doping and covalent functionalization are outlined, which show great advantages in boosting the Li storage performances because of the additionally introduced defect/active sites for further Li accommodation. Furthermore, binder-free and free-standing graphene electrodes are presented, exhibiting great prospects for high-energy-density and flexible LIBs. Finally, the remaining challenges and future opportunities of practically available graphene anodes for advanced LIBs are highlighted.

11.
ACS Appl Mater Interfaces ; 15(4): 5172-5179, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36650087

RESUMO

CuO has been regarded as a promising catalyst for the electrochemical reduction of nitrate (NO3-RR) to ammonium (NH3); however, the intrinsic activity is greatly restricted by its poor electrical property. In this work, self-supported Zn-doped CuO nanosheet arrays (Zn-CuO NAs) are synthesized for NO3-RR, where the Zn dopant regulates the electronic structure of CuO to significantly accelerate the interfacial charge transfer and inner electron transport kinetics. The Zn-CuO NAs are constructed by a one-step etching of commercial brass (Cu64Zn36 alloy) in 0.1 M NaOH solution, which experiences a corrosion-oxidation-reconstruction process. Initially, the brass undergoes a dealloying procedure to produce nanosized Cu, which is immediately oxidized to the Cu2O unit with a low valence state. Subsequently, Cu2O is further oxidized to the CuO unit and reconstructed into nanosheets with the coprecipitation of Zn2+. For NO3-RR, Zn-CuO NAs show a high NH3 production rate of 945.1 µg h-1 cm-2 and a Faradaic efficiency of up to 95.6% at -0.7 V in 0.1 M Na2SO4 electrolyte with 0.01 M NaNO3, which outperforms the majority of the state-of-the-art catalysts. The present work offers a facile yet very efficient strategy for the scale-up synthesis of Zn-CuO NAs for high-performance NH3 production from NO3-RR.

12.
Adv Mater ; 35(29): e2211168, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36756778

RESUMO

Lithium-sulfur batteries (LSBs) with superior energy density are among the most promising candidates of next-generation energy storage techniques. As the key step contributing to 75% of the overall capacity, Li2 S deposition remains a formidable challenge for LSBs applications because of its sluggish kinetics. The severe kinetic issue originates from the huge interfacial impedances, indicative of the interface-dominated nature of Li2 S deposition. Accordingly, increasing efforts have been devoted to interface engineering for efficient Li2 S deposition, which has attained inspiring success to date. However, a systematic overview and in-depth understanding of this critical field are still absent. In this review, the principles of interface-controlled Li2 S precipitation are presented, clarifying the pivotal roles of electrolyte-substrate and electrolyte-Li2 S interfaces in regulating Li2 S depositing behavior. For the optimization of the electrolyte-substrate interface, efforts on the design of substrates including metal compounds, functionalized carbons, and organic compounds are systematically summarized. Regarding the regulation of electrolyte-Li2 S interface, the progress of applying polysulfides catholytes, redox mediators, and high-donicity/polarity electrolytes is overviewed in detail. Finally, the challenges and possible solutions aiming at optimizing Li2 S deposition are given for further development of practical LSBs. This review would inspire more insightful works and, more importantly, may enlighten other electrochemical areas concerning heterogeneous deposition processes.

13.
Research (Wash D C) ; 6: 0209, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37593340

RESUMO

Soft carbons have attracted extensive interests as competitive anodes for fast-charging sodium-ion batteries (SIBs); however, the high-rate performance is still restricted by their large ion migration barriers and sluggish reaction kinetics. Herein, we show a molecular design approach toward the fabrication of nitrogen and phosphorus codoped mesoporous soft carbon (NPSC). The key to this strategy lies in the chemical cross-linking reaction between polyphosphoric acid and p-phenylenediamine, associated with pyrolysis induced in-situ self-activation that creates mesoporous structures and rich heteroatoms within the carbon matrix. Thanks to the enlarged interlayer spacing, reduced ion diffusion length, and plentiful active sites, the obtained NPSC delivers a superb rate capacity of 215 mAh g-1 at 10 A g-1 and an ultralong cycle life of 4,700 cycles at 5 A g-1. Remarkably, the full cell shows 99% capacity retention during 100 continuous cycles, and maximum energy and power densities of 191 Wh kg-1 and 9.2 kW kg-1, respectively. We believe that such a synthetic protocol could pave a novel venue to develop soft carbons with unique properties for advanced SIBs.

14.
Adv Sci (Weinh) ; 10(23): e2301288, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37311206

RESUMO

3D Cu current collectors have been demonstrated to improve the cycling stability of Li metal anodes, however, the role of their interfacial structure for Li deposition pattern has not been investigated thoroughly. Herein, a series of 3D integrated gradient Cu-based current collectors are fabricated by the electrochemical growth of CuO nanowire arrays on Cu foil (CuO@Cu), where their interfacial structures can be readily controlled by modulating the dispersities of the nanowire arrays. It is found that the interfacial structures constructed by sparse and dense dispersion of CuO nanowire arrays are both disadvantageous for the nucleation and deposition of Li metal, consequently fast dendrite growth. In contrast, a uniform and appropriate dispersity of CuO nanowire arrays enables stable bottom Li nucleation associated with smooth lateral deposition, affording the ideal bottom-up Li growth pattern. The optimized CuO@Cu-Li electrodes exhibit a highly reversible Li cycling including a coulombic efficiency of up to ≈99% after 150 cycles and a long-term lifespan of over 1200 h. When coupling with LiFePO4 cathode, the coin and pouch full-cells deliver outstanding cycling stability and rate capability. This work provides a new insight to design the gradient Cu current collectors toward high-performance Li metal anodes.

15.
Adv Mater ; 35(48): e2307017, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37821238

RESUMO

Nanoarray electrocatalysts with unique advantage of facilitating gas bubble detachment have garnered significant interest in gas evolution reactions (GERs). Existing research is largely based on a static hypothesis, assuming that buoyancy is the only driving force for the release of bubbles during GERs. However, this hypothesis overlooks the effect of the self-dynamic electrolyte flow, which is induced by the release of mature bubbles and helps destabilize and release the smaller, immature bubbles nearby. Herein, the enhancing effect of self-dynamic electrolyte flow on nanoarray structures is examined. Phase-field simulations demonstrate that the flow field of electrode with arrayed surface focuses shear force directly onto the gas bubble for efficient detachment, due to the flow could pass through voids and channels to bypass the shielding effect. The flow field therefore has a more substantial impact on the arrayed surface than the nanoscale smooth surface in terms of reducing the critical bubble size. To validate this, superaerophobic ferrous-nickel sulfide nanoarrays are fabricated and employed for water splitting, which display improved efficiency for GERs. This study contributes to understanding the influence of self-dynamic electrolyte on GERs and emphasizes that it should be considered when designing and evaluating nanoarray electrocatalysts.

16.
Chem Commun (Camb) ; 59(81): 12140-12143, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37740333

RESUMO

Placing blocking layers between electrodes has shown paramount prospects in suppressing the shuttle effect of Li-S batteries, but the associated ionic transport would be a concurrent obstacle. Herein, we present a Li-based crystal composited with carbon (LiPN2@C) by a one-step annealing of Li+ absorbed melamine polyphosphate, which simultaneously achieves alleviated polysulfide-shuttling and facilitated Li+ transport. As a homologous crystal, LiPN2 with abundant lithiophilic sites makes Li+ transport more efficient and sustainable. With a LiPN2@C-modified separator, the Li2S cathode exhibits a much-lower activation potential of 2.4 V and a high-rate capacity of 519 mA h g-1 at 2C. Impressively, the battery delivers a capacity of 726 mA h g-1 at 0.5C with a low decay rate of 0.25% per cycle during 100 continuous cycles.

17.
Adv Mater ; 34(37): e2204624, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35866182

RESUMO

Developing high-efficiency electrocatalysts for the hydrogen evolution and oxidation reactions (HER/HOR) in alkaline electrolytes is of critical importance for realizing renewable hydrogen technologies. Ruthenium phosphides (RuPx ) are promising candidates to substitute Pt-based electrodes; however, great challenges still remain in their electronic structure regulation for optimizing intermediate adsorption. Herein, it is reported that a homologous RuP@RuP2 core-shell architecture constructed by a phosphatization-controlled phase-transformation strategy enables strong electron coupling for optimal intermediate adsorption by virtue of the emergent interfacial functionality. Density functional theory calculations show that the RuP core and RuP2 shell present efficient electron transfer, leading to a close to thermoneutral hydrogen adsorption Gibbs free energy of 0.04 eV. Impressively, the resulting material exhibits superior HER/HOR activities in alkaline media, which outperform the benchmark Pt/C and are among the best reported bifunctional hydrogen electrocatalysts. The present work not only provides an efficient and cost-effective bifunctional hydrogen electrocatalyst, but also offers a new synthetic protocol to rationally synthesize homologous core-shell nanostructures for widespread applications.

18.
Chem Commun (Camb) ; 57(32): 3885-3888, 2021 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-33871503

RESUMO

Potassium-ion batteries (PIBs) are attracting increasing attention due to the abundance of K resources, but the sluggish kinetics and inferior cycling stability of anodes still hinder their application. Herein, we present a hybrid 1T/2H phase MoSe2 anode, which shows noticeable pseudocapacitive response and fast kinetics for K storage. Correspondingly, superior electrochemical performances including a high reversible capacity of 440 mA h g-1 after 100 cycles at 0.1 A g-1 and superb rate capacity of 211 mA h g-1 at 20.0 A g-1 are achieved. We believe this work may shed light on the phase engineering of transition metal compounds for rapid charging PIBs.

19.
Adv Mater ; 33(10): e2003845, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33491836

RESUMO

Li-chalcogen batteries, especially the Li-S batteries (LSBs), have received paramount interests as next generation energy storage techniques because of their high theoretical energy densities. However, the associated challenges need to be overcome prior to their commercialization. Elemental selenium, another chalcogen member, would be an attractive alternative to sulfur owing to its higher electronic conductivity, comparable capacity density, and moreover, excellent compatibility with carbonate electrolytes. Unlike LSBs, the research and development of Li-Se batteries (LSeBs) have garnered burgeoning attention but are still in their infant stage, where a comprehensive yet in-depth overview is highly imperative to guide future research. Herein, a critical review of LSeBs, in terms of the underlying mechanisms, cathode design, blocking layer engineering, and emerging solid-state electrolytes is provided. First, the electrolyte-dependent electrochemistry of LSeBs is discussed. Second, the advances in Se-based cathodes are comprehensively summarized, especially highlighting the state-of-the-art Sex Sy cathodes, and mainly focusing on their structures, compositions, and synthetic strategies. Third, the versatile separators/interlayers optimization and interface regulation are outlined, with a particular focus on the emerging solid-state electrolytes for advanced LSeBs. Last, the remaining challenges and research orientations in this booming field are proposed, which are expected to motivate more insightful works.

20.
Adv Mater ; 33(11): e2005587, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33569838

RESUMO

Layered γ-type iron oxyhydroxide (γ-FeOOH) is a promising material for various applications; however, its sheet-shaped structure often suffers from instability that results in aggregation and leads to inferior performance. Herein, a kinetically controlled hydrolysis strategy is proposed for the scalable synthesis of γ-FeOOH nanosheets arrays (NAs) with enhanced structural stability on diverse substrates at ambient conditions. The underlying mechanisms for the growth of γ-FeOOH NAs associated with their structural evolution are systematically elucidated by alkalinity-controlled synthesis and time-dependent experiments. As a proof-of-concept application, γ-FeOOH NAs are developed as electrocatalysts for the oxygen evolution reaction (OER), where the sample grown on nickel foam (NF) exhibits superior performance of high catalytic current density, small Tafel slope, and exceptional durability, which is among the top level of FeOOH-based electrocatalysts. Density functional theory calculations suggest that γ-NiOOH in situ generated from the electrooxidation of NF would induce charge accumulation on the Fe sites of γ-FeOOH NAs, leading to enhanced OER intermediates adsorption for water splitting. This work affords a new technique to rationally design and synthesize γ-FeOOH NAs for various applications.

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