Support and Interface Effects in Water‐Splitting Electrocatalysts

Advanced Materials, Journal Year: 2019, Volume and Issue: 31(31)

Published: March 6, 2019

Water-splitting electrolyzers that can convert electricity into storable hydrogen are a fascinating and scalable energy conversion technology for the utilization of renewable energies. To speed up sluggish oxygen evolution reactions (HER OER), electrocatalysts essential reducing their kinetic barriers eventually improving efficiency. As efficient strategies modulating binding ability water-splitting intermediates on electrocatalyst surface, support effect interface drawing growing attention. Herein, some recent research progress effects in HER, OER, overall is highlighted. Specifically, correlation between electronic interaction constituent components electrocatalytic performance profoundly discussed, with aim advancing development highly electrocatalysts, which may replace noble-metal-based bring practically widespread reality.

Language: Английский

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2D Layered Double Hydroxides for Oxygen Evolution Reaction: From Fundamental Design to Application

Advanced Energy Materials, Journal Year: 2019, Volume and Issue: 9(17)

Published: March 3, 2019

Abstract The oxygen evolution reaction (OER) has aroused extensive interest from materials scientists in the past decade by virtue of its great significance energy storage/conversion systems such as water splitting, rechargeable metal–air batteries, carbon dioxide (CO 2 ) reduction, and fuel cells. Among all capable catalyzing OER, layered double hydroxides (LDHs) stand out one most effective electrocatalysts owing to their compositional structural flexibility well tenability simplicity preparation process. For this reason, numerous efforts have been dedicated adjusting structure, forming well‐defined morphology, developing methods LDHs promote electrocatalytic performance. In article, recent advances rational design LDH‐based toward OER are summarized. Specifically, various tactics for synthetic methods, composition regulations LDHs, further highlighted, followed a discussion on influential factors Finally, remaining challenges investigate improve ability LDH stated indicate possible future development LDHs.

Language: Английский

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Synergistic coupling of CoFe-LDH arrays with NiFe-LDH nanosheet for highly efficient overall water splitting in alkaline media

Applied Catalysis B Environment and Energy, Journal Year: 2019, Volume and Issue: 253, P. 131 - 139

Published: April 18, 2019

Language: Английский

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Defect‐Rich Heterogeneous MoS₂/NiS₂ Nanosheets Electrocatalysts for Efficient Overall Water Splitting

Advanced Science, Journal Year: 2019, Volume and Issue: 6(14)

Published: May 20, 2019

Abstract Designing and constructing bifunctional electrocatalysts is vital for water splitting. Particularly, the rational interface engineering can effectively modify active sites promote electronic transfer, leading to improved splitting efficiency. Herein, free‐standing defect‐rich heterogeneous MoS 2 /NiS nanosheets overall are designed. The abundant interfaces in not only provide rich electroactive but also facilitate electron which further cooperate synergistically toward electrocatalytic reactions. Consequently, optimal show enhanced performances as This study may open up a new route rationally maximize their electrochemical performances, help accelerate development of nonprecious

Language: Английский

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Interface Engineering of Hierarchical Branched Mo‐Doped Ni₃S₂/Ni_xP_y Hollow Heterostructure Nanorods for Efficient Overall Water Splitting

Advanced Energy Materials, Journal Year: 2020, Volume and Issue: 10(17)

Published: March 16, 2020

Abstract Rational design and construction of bifunctional electrocatalysts with excellent activity durability is imperative for water splitting. Herein, a novel top‐down strategy to realize hierarchical branched Mo‐doped sulfide/phosphide heterostructure (Mo‐Ni 3 S 2 /Ni x P y hollow nanorods), by partially phosphating Mo‐Ni /NF flower clusters, proposed. Benefitting from the optimized electronic structure configuration, nanorod structure, abundant heterogeneous interfaces, as‐obtained multisite electrode has remarkable stability electrocatalytic in hydrogen evolution reaction (HER)/oxygen (OER) 1 m KOH solutions. It possesses an extremely low overpotential 238 mV at current density 50 mA cm −2 OER. Importantly, when assembled as anode cathode simultaneously, it merely requires ultralow cell voltage 1.46 V achieve 10 , over 72 h, outperforming most reported Ni‐based materials. Density functional theory results further confirm that doped can synergistically optimize Gibbs free energies H O‐containing intermediates (OH*, O*, OOH*) during HER OER processes, thus accelerating catalytic kinetics electrochemical This work demonstrates importance rational combination metal doping interface engineering advanced

Language: Английский

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Heterogeneous Bimetallic Phosphide Ni₂P‐Fe₂P as an Efficient Bifunctional Catalyst for Water/Seawater Splitting

Advanced Functional Materials, Journal Year: 2020, Volume and Issue: 31(1)

Published: Sept. 28, 2020

Abstract Developing high‐performance and cost‐effective bifunctional electrocatalysts for large‐scale water electrolysis is desirable but remains a significant challenge. Most existing nano‐ micro‐structured require complex synthetic procedures, making scale‐up highly challenging. Here, heterogeneous Ni 2 P‐Fe P microsheet synthesized by directly soaking foam in hydrochloric acid an iron nitrate solution, followed phosphidation. Benefiting from high intrinsic activity, abundant active sites, superior transfer coefficient, this self‐supported electrocatalyst shows superb catalytic activity toward overall splitting, requiring low voltages of 1.682 1.865 V to attain current densities 100 500 mA cm −2 1 m KOH, respectively. Such performance the benchmark IrO || Pt/C pair also places among best catalysts reported thus far. Furthermore, its enhanced corrosion resistance hydrophilic surface make it suitable seawater splitting. It able achieve KOH at 1.811 2.004 V, respectively, which, together with robust durability, demonstrates great potential realistic electrolysis. This work presents general economic approach fabrication metallic phosphide water/seawater electrocatalysis.

Language: Английский

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Layered double hydroxide-based electrocatalysts for the oxygen evolution reaction: identification and tailoring of active sites, and superaerophobic nanoarray electrode assembly

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(15), P. 8790 - 8817

Published: Jan. 1, 2021

The electrocatalytic oxygen evolution reaction (OER) is a critical half-cell for hydrogen production via water electrolysis. However, the practical OER suffers from sluggish kinetics and thus requires efficient electrocatalysts. Transition metal-based layered double hydroxides (LDHs) represent one of most active classes catalysts. An in-depth understanding activity LDH based electrocatalysts can promote further rational design site regulation high-performance In this review, fundamental structural characteristics LDHs demonstrated first, then comparisons discussions recent advances in as highly catalysts alkaline media are offered, which include both experimental computational methods. On top identification characterization on an atomic scale, strategies to summarised, including doping, intercalation defect-making. Furthermore, concept superaerophobicity, has profound impact performance gas electrodes, explored enhance their derivatives large scale OER. addition, certain operating standards measurements proposed avoid inconsistency evaluating LDHs. Finally, several key challenges using anode materials splitting, such issue stability adoption membrane-electrode-assembly electrolysers, emphasized shed light future research directions.

Language: Английский

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Recent progress on earth abundant electrocatalysts for hydrogen evolution reaction (HER) in alkaline medium to achieve efficient water splitting – A review

Journal of Energy Chemistry, Journal Year: 2018, Volume and Issue: 34, P. 111 - 160

Published: Sept. 26, 2018

Language: Английский

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Co‐Induced Electronic Optimization of Hierarchical NiFe LDH for Oxygen Evolution

Small, Journal Year: 2020, Volume and Issue: 16(38)

Published: Aug. 20, 2020

Abstract Developing efficient and stable non‐noble electrocatalysts for the oxygen evolution reaction (OER) remains challenging practical applications. While nickel–iron layered double hydroxides (NiFe‐LDH) are emerging as prominent candidates with promising OER activity, their catalytic performance is still restricted by limited active sites, poor conductivity durability. Herein, hierarchical nickel–iron–cobalt LDH nanosheets/carbon fibers (NiFeCo‐LDH/CF) synthesized through solvent‐thermal treatment of ZIF‐67/CF. Extended X‐ray adsorption fine structure analyses reveal that Co substitution can stabilize Fe local coordination environment facilitate π‐symmetry bonding orbital in NiFeCo‐LDH/CF, thus modifying electronic structures. Coupling structural advantages, including largely exposed surface sites facilitated charge transfer pathway ensured CF, resultant NiFeCo‐LDH/CF exhibits excellent activity an overpotential 249 mV at 10 mA cm −1 well robust stability over 20 h.

Language: Английский

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Ni Strongly Coupled with Mo₂C Encapsulated in Nitrogen‐Doped Carbon Nanofibers as Robust Bifunctional Catalyst for Overall Water Splitting

Advanced Energy Materials, Journal Year: 2019, Volume and Issue: 9(10)

Published: Jan. 28, 2019

Abstract It is urgently required to develop highly efficient and stable bifunctional non‐noble metal electrocatalysts for both the hydrogen evolution reaction (HER) oxygen (OER) water splitting. In this study, a facile electrospinning followed by post‐carbonization treatment synthesize nitrogen‐doped carbon nanofibers (NCNFs) integrated with Ni Mo 2 C nanoparticles (Ni/Mo C‐NCNFs) as splitting developed. Owing strong binding energy on high electrical conductivity of Ni, synergetic effect between significantly promote HER OER activities. The optimized hybrid C(1:2)‐NCNFs) delivers low overpotentials 143 mV 288 at current density 10 mA cm −2 . An alkaline electrolyzer Ni/Mo C(1:2)‐NCNFs catalysts anode cathode exhibits voltage 1.64 V, which only 0.07 V larger than benchmark Pt/C‐RuO electrodes. addition, an outstanding long‐term durability during 100 h testing without obvious degradation achieved, superior most noble‐metal‐free reported date. This work provides simple effective approach preparation low‐cost high‐performance overall

Language: Английский

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