Bifunctional Heterostructure Assembly of NiFe LDH Nanosheets on NiCoP Nanowires for Highly Efficient and Stable Overall Water Splitting

Advanced Functional Materials, Год журнала: 2018, Номер 28(14)

Опубликована: Янв. 31, 2018

Abstract 3D hierarchical heterostructure NiFe LDH@NiCoP/NF electrodes are prepared successfully on nickel foam with special interface engineering and synergistic effects. This research finds that the as‐prepared have a more sophisticated inner structure intensive than simple physical mixture. The require an overpotential as low 120 220 mV to deliver 10 mA cm −2 for hydrogen evolution reaction (HER) oxygen (OER) in 1 m KOH, respectively. Tafel electrochemical impedance spectroscopy further reveal favorable kinetic during electrolysis. Specifically, simultaneously used cathode anode overall water splitting, which requires cell voltage of 1.57 V at . Furthermore, effect improves structural stability promotes generation active phases HER OER, resulting excellent over 100 h continuous operation. Moreover, strategy introduced can also be prepare other bifunctional cost‐efficient electrocatalysts various applications.

Язык: Английский

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Accelerated Hydrogen Evolution Kinetics on NiFe‐Layered Double Hydroxide Electrocatalysts by Tailoring Water Dissociation Active Sites

Advanced Materials, Год журнала: 2018, Номер 30(10)

Опубликована: Янв. 19, 2018

Abstract Owing to its earth abundance, low kinetic overpotential, and superior stability, NiFe‐layered double hydroxide (NiFe‐LDH) has emerged as a promising electrocatalyst for catalyzing water splitting, especially oxygen evolution reaction (OER), in alkaline solutions. Unfortunately, result of extremely sluggish dissociation kinetics (Volmer step), hydrogen (HER) activity the NiFe‐LDH is rather poor environment. Here novel strategy demonstrated substantially accelerating by partially substituting Fe atoms with Ru. In 1 m KOH solution, as‐synthesized Ru‐doped nanosheets (NiFeRu‐LDH) exhibit excellent HER performance an overpotential 29 mV at 10 mA cm −2 , which much lower than those noble metal Pt/C reported electrocatalysts. Both experimental theoretical results reveal that introduction Ru into can efficiently reduce energy barrier Volmer step, eventually kinetics. Benefitting from outstanding remained OER activity, NiFeRu‐LDH steadily drives electrolyzer current density cell voltage 1.52 V, values Pt/C–Ir/C couple state‐of‐the‐art overall water‐splitting

Язык: Английский

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Hierarchical Nanoassembly of MoS₂/Co₉S₈/Ni₃S₂/Ni as a Highly Efficient Electrocatalyst for Overall Water Splitting in a Wide pH Range

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(26), С. 10417 - 10430

Опубликована: Июнь 6, 2019

The design of low-cost yet high-efficiency electrocatalysts for hydrogen evolution reaction (HER) and oxygen (OER) over a wide pH range is highly challenging. We now report hierarchical co-assembly interacting MoS2 Co9S8 nanosheets attached on Ni3S2 nanorod arrays which are supported nickel foam (NF). This tiered structure endows high performance toward HER OER very broad range. By adjusting the molar ratio Co:Mo precursors, we have created CoMoNiS-NF- xy composites ( x: y means ratios ranging from 5:1 to 1:3) with controllable morphology composition. three-dimensional an abundance active sites capable universal catalytic activity. CoMoNiS-NF-31 demonstrates best electrocatalytic activity, giving ultralow overpotentials (113, 103, 117 mV 166, 228, 405 OER) achieve current density 10 mA cm-2 in alkaline, acidic, neutral electrolytes, respectively. It also shows remarkable balance between activity stability. Based distinguished OER, demonstrate two-electrode electrolyzer performing water electrolysis range, low cell voltages 1.54, 1.45, 1.80 V at media, First-principles calculations suggest that arises electron transfer interface, alters binding energies adsorbed species decreases overpotentials. Our results metal sulfides can serve as efficient all-pH (pH = 0-14) overall splitting.

Язык: Английский

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Identification of single-atom active sites in carbon-based cobalt catalysts during electrocatalytic hydrogen evolution

Nature Catalysis, Год журнала: 2018, Номер 2(2), С. 134 - 141

Опубликована: Дек. 13, 2018

Язык: Английский

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Multifunctional Mo–N/C@MoS₂ Electrocatalysts for HER, OER, ORR, and Zn–Air Batteries

Advanced Functional Materials, Год журнала: 2017, Номер 27(44)

Опубликована: Сен. 29, 2017

Abstract Replacement of noble‐metal platinum catalysts with cheaper, operationally stable, and highly efficient electrocatalysts holds huge potential for large‐scale implementation clean energy devices. Metal–organic frameworks (MOFs) metal dichalcogenides (MDs) offer rich platforms design active owing to their flexibility, ultrahigh surface area, hierarchical pore structures, high catalytic activity. Herein, an advanced electrocatalyst based on a vertically aligned MoS 2 nanosheet encapsulated Mo–N/C framework interfacial Mo–N coupling centers is reported. The hybrid structure exhibits robust multifunctional electrocatalytic activity stability toward the hydrogen evolution reaction, oxygen reduction reaction. Interestingly, it further displays high‐performance Zn–air batteries as cathode power density ≈196.4 mW cm −2 voltaic efficiency ≈63 % at 5 mA , well excellent cycling even after 48 h 25 . Such outstanding properties stem from synergistic effect distinct chemical composition, unique three‐phase sites, fast mass transport. This work expected inspire performance‐oriented MOF/MD hybrid‐based wider application in electrochemical

Язык: Английский

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Ni–Mo–O nanorod-derived composite catalysts for efficient alkaline water-to-hydrogen conversion via urea electrolysis

Energy & Environmental Science, Год журнала: 2018, Номер 11(7), С. 1890 - 1897

Опубликована: Янв. 1, 2018

Two Ni–Mo–O compounds show exceptional cathodic/anodic catalytic performance for urea electrolysis, suggesting a promising route to energy-saving H₂ production.

Язык: Английский

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Self‐Templating Synthesis of Hollow Co₃O₄ Microtube Arrays for Highly Efficient Water Electrolysis

Angewandte Chemie International Edition, Год журнала: 2016, Номер 56(5), С. 1324 - 1328

Опубликована: Ноя. 30, 2016

Abstract In spite of recent advances in the synthesis hollow micro/nanostructures, fabrication three‐dimensional electrodes on basis these structures remains a major challenge. Herein, we develop an electrochemical sacrificial‐template strategy to fabricate Co 3 O 4 microtube arrays with hierarchical porosity. The resultant unique and integrated electrode configurations impart enhanced mass transfer electron mobility, ensuring high activity stability catalyzing oxygen hydrogen evolution reactions. Impressively, apparent performance can rival that state‐of‐the‐art noble‐metal transition‐metal electrocatalysts. Furthermore, this bifunctional be used for highly efficient overall water splitting, even competing Pt/C IrO 2 /C.

Язык: Английский

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Non-precious-metal catalysts for alkaline water electrolysis: operando characterizations, theoretical calculations, and recent advances

Chemical Society Reviews, Год журнала: 2020, Номер 49(24), С. 9154 - 9196

Опубликована: Янв. 1, 2020

Advances of non-precious-metal catalysts for alkaline water electrolysis are reviewed, highlighting operando techniques and theoretical calculations in their development.

Язык: Английский

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Efficient Hydrogen Evolution on Cu Nanodots-Decorated Ni₃S₂ Nanotubes by Optimizing Atomic Hydrogen Adsorption and Desorption

Journal of the American Chemical Society, Год журнала: 2017, Номер 140(2), С. 610 - 617

Опубликована: Окт. 23, 2017

Low-cost transition-metal dichalcogenides (MS2) have attracted great interest as alternative catalysts for hydrogen evolution. However, a significant challenge is the formation of sulfur–hydrogen bonds on MS2 (S–Hads), which will severely suppress evolution reaction (HER). Here we report Cu nanodots (NDs)-decorated Ni3S2 nanotubes (NTs) supported carbon fibers (CFs) (Cu NDs/Ni3S2 NTs-CFs) efficient electrocatalysts HER in alkaline media. The electronic interactions between and result NDs that are positively charged can promote water adsorption activation. Meanwhile, NTs negatively weaken S–Hads formed catalyst surfaces. Therefore, Cu/Ni3S2 hybrids optimize H desorption both Volmer Heyrovsky steps HER. strong cause NTs-CFs to exhibit outstanding catalytic performance with low onset potential, high activity, excellent stability.

Язык: Английский

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3D Nitrogen‐Anion‐Decorated Nickel Sulfides for Highly Efficient Overall Water Splitting

Advanced Materials, Год журнала: 2017, Номер 29(30)

Опубликована: Июнь 9, 2017

Developing non‐noble‐metal electrocatalysts with high activity and low cost for both the oxygen evolution reaction (OER) hydrogen (HER) is of paramount importance improving generation H 2 fuel by electrocatalytic water‐splitting. This study puts forward a new N‐anion‐decorated Ni 3 S material synthesized simple one‐step calcination route, acting as superior bifunctional electrocatalyst OER/HER first time. The introduction N anions significantly modifies morphology electronic structure , bringing surface active sites exposure, enhanced electrical conductivity, optimal HER Gibbs free‐energy (ΔG H* ), water adsorption energy change H2O* ). Remarkably, obtained N‐Ni /NF 3D electrode exhibits extremely overpotentials 330 110 mV to reach current density 100 10 mA cm −2 OER in 1.0 m KOH, respectively. Moreover, an overall water‐splitting device comprising this delivers at very cell voltage 1.48 V. Our finding introduces way design advanced catalysts splitting.

Язык: Английский

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