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

et al. 2020

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are required. [2a,b,3] Among the various sustainable energy candidates, hydrogen fuel has garnered significant attention owing to its natural advantages. Hydrogen is typically a nontoxic and environmentally friendly power source that can be produced from water, which is an earth-abundant reactant, and produces no CO 2 emissions when converted into other energy forms. [4-6] In addition, due to its high mass-specific energy density, hydrogen can be efficiently used in mobile applications. Moreover, hydrogen can be used in combustion engines and fuel cells. Hence, the development of efficient hydrogen-based energy systems is necessary. [7-9] Producing hydrogen by electrolytic water splitting is considered a promising approach to resolve the current environmental crisis and has been extensively investigated with emphasis on availability and sustainability. [10,11] During water electrolysis, the cathodic hydrogen evolution reaction (HER) [12] and the anodic oxygen evolution reaction (OER) occur simultaneously, as exemplified by the following equations

Section: The Nife-layered Hydroxide (Nife-ldh) Familysupporting

confidence: 69%

Recent Progress on NiFe‐Based Electrocatalysts for the Oxygen Evolution Reaction

Zhao

et al. 2020

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239

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“…The results displayed that CoN x @GDY NS/NF only needed relatively low cell voltage of 1.48 V to achieve the current density of 10 mA cm −2 , which was lower than that of other prepared materials and comparable to or even slightly superior to that of recently developed catalysts ( Table 2 ). [ 142–156 ] Furthermore, this CoN x @GDY NS/NF also stayed almost high current density of 10 mA cm −2 within 20 hours, further corroborating its strong durability.…”

Section: Gdy Supported Electrocatalysts For Energy Conversionmentioning

confidence: 64%

Graphdiyne: A Rising Star of Electrocatalyst Support for Energy Conversion

Lai

Advanced Energy Materials

et al. 2020

110

Graphdiyne (GDY), a rising star of 2D carbon allotropes with one‐atom‐thick planar layers, has achieved the coexistence of sp‐ and sp2‐hybridized carbon atoms in a 2D planar structure. In contrast to the prevailing carbon allotropes, GDY possesses Dirac cone structures, which endow it with unique chemical and physical properties, including an adjustable inherent bandgap, high‐speed charge carrier transfer efficiency, and excellent conductivity. Additionally, GDY also displays great potential in photocatalysis, rechargeable batteries, solar cells, detectors, and especially electrocatalysis. In this work, various GDY‐supported electrocatalysts are described and the reasons why GDY can act as a novel support are analyzed from the perspective of molecular structure, electronic properties, mechanical properties, and stability. The various electrochemical applications of GDY‐supported electrocatalysts in energy conversion such as hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, overall water splitting, and nitrogen reduction reaction are reviewed. The challenges facing GDY and GDY‐based materials in future research are also outlined. This review aims at providing an in‐depth understanding of GDY and promoting the development and application of this novel carbon material.

“…[49] In the fitting peaks of Fe 2p (Figure 4c), the peak around 711.3 eV corresponded to Fe 2p 3/2 of Fe 3 + and that at 717.9 eV was assigned to the satellite peak of Fe 2p 3/2 . [50] For comparison, the surface electronic states of Co/CoFeÀ C photocatalyst were also tested ( Figure S7). Compared with the carbonate intercalated CoFeÀ C, the bonding energy of Co and Fe in the CoFeÀ Mo carrier had no obvious change after the molybdate intercalated the carrier.…”

Section: Characterization Of Catalystsmentioning

confidence: 99%

Photocatalytic H₂ Evolution from Ammonia Borane: Improvement of Charge Separation and Directional Charge Transmission

Cheng

et al. 2020

ChemSusChem

Co/M II Fe layered double hydroxide (LDH) LDH photocatalysts have been designed from the aspect of employing stable halffilled Fe 3 + to trap photogenerated electrons, adjusting the M II À OÀ Fe oxo-bridged structure to optimize the short-range directional charge transmission and intercalating oxometallate anions into the LDH to further improve light absorption along with electron-hole separation and non-noble metal Co NP loading and reduction to form a heterojunction. These LDHbased photocatalysts are employed for photocatalytic H 2 evolution from ammonia borane in aqueous solution under visible light at 298 K. The photocatalytic H 2 evolution activity is greatly improved through adjustment of the M II À OÀ Fe oxobridged structure and molybdate intercalation into the LDH. Turnover frequencies of up to 113.2 min À 1 are achieved with Co/CoFeÀ Mo. Alongside the experimental results and materials characterization, capture experiments and in situ DRIFTS analysis are carried out to study the photocatalytic hydrogen production mechanism.