| 1. |
- Hou, Jungang, et al.
(författare)
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Rational Design of Nanoarray Architectures for Electrocatalytic Water Splitting
- 2019
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Ingår i: Advanced Functional Materials. - : Wiley-VCH Verlagsgesellschaft. - 1616-301X .- 1616-3028. ; 29:20
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Forskningsöversikt (refereegranskat)abstract
- Electrochemical water splitting is recognized as a practical strategy for impelling the transformation of sustainable energy sources such as solar energy from electricity to clean hydrogen fuel. To actualize the large-scale hydrogen production, it is paramount to develop low-cost, earth-abundant, efficient, and stable electrocatalysts. Among those electrocatalysts, alternative architectural arrays grown on conductive substrates have been proven to be highly efficient toward water splitting due to large surface area, abundant active sites, and synergistic effects between the electrocatalysts and the substrates. Herein, the advancement of nanoarray architectures in electrocatalytic applications is reviewed. The categories of different nanoarrays and the reliable and versatile synthetic approaches of electrocatalysts are summarized. A unique emphasis is highlighted on the promising strategies to enhance the electrocatalytic activities and stability of architectural arrays by component manipulation, heterostructure regulation, and vacancy engineering. The intrinsic mechanism analysis of electronic structure optimization, intermediates' adsorption facilitation, and coordination environments' amelioration is also discussed with regard to theoretical simulation and in situ identification. Finally, the challenges and opportunities on the valuable directions and promising pathways of architectural arrays toward outstanding electrocatalytic performance are provided in the energy conversion field, facilitating the development of promising water splitting systems.
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| 2. |
- Li, Zhuwei, et al.
(författare)
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Two-dimensional Janus heterostructures for superior Z-scheme photocatalytic water splitting
- 2019
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Ingår i: Nano Energy. - : Elsevier BV. - 2211-2855 .- 2211-3282. ; 59, s. 537-544
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Tidskriftsartikel (refereegranskat)abstract
- Developing robust water splitting photocatalyst remains a pivot challenge for solar-to-fuel conversion. Herein, two-dimensional (2D) Janus bilayer heterostructures are reported by sulfur-vacancy-confined-in ZnIn2S4 (V-s-ZnIn2S4) and WO3 nanosheets as an all-solid-state Z-scheme prototype. First-principle calculations and experimental observations clearly confirm the spontaneous formation of this redox-mediator-free Z-scheme van der Waals heterostructure at atomic level, not only facilitating the space separation of photoexcited carriers with high charge density, enhancing charge dynamics and optimizing charge lifetime, but also accumulating electrons in conduction band of V-s-ZnIn2S4 and holes in valence band of WO3 by internal electric field through W-S bonds. After integrated by NiS quantum dots, novel 2D/2D NiS/V-s-ZnIn2S4/WO3 heterostructures with high stability exhibited an outstanding visible-light hydrogen evolution rate of 11.09 mmol g(-1)h(-1) and an apparent quantum efficiency about 72% at 420 nm, the highest value so far reported among the family of ZnIn(2)S(4 )photocatalysts. This work not only presents novel Janus heterostructures but also paves the atomic-level structural and interfacial design and the construction of 2D Janus bilayer Z-scheme heterojunctions for solar energy conversion applications.
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| 3. |
- Zhang, Bo, et al.
(författare)
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Tailoring Active Sites in Mesoporous Defect-Rich NC/V-o-WON Heterostructure Array for Superior Electrocatalytic Hydrogen Evolution
- 2019
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Ingår i: Advanced Energy Materials. - : WILEY-V C H VERLAG GMBH. - 1614-6832 .- 1614-6840. ; 9:12
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Tidskriftsartikel (refereegranskat)abstract
- Tailoring active sites in earth-abundant non-noble metal electrocatalysts are required toward widespread applications in sustainable energy fields. Herein, an integrated mesoporous heterostructure array is reported by a hydrogenation/nitridation-induced in situ growth strategy. Highly conductive oxygen-vacancies-rich tungsten oxynitride (V-o-WON) nanorod array acts as the backbone encapsulated by ultrathin nitrogen-doped carbon (NC) nanolayers, forming high-quality shell/core NC/V-o-WON heterostructures. Density functional theory calculations reveal that defect-rich heterostructure arrays not only enhance the conductivity and modulate electronic structure but also promote the adsorption and dissociation of reactants and offer substantial potential sites. As expected, porous NC/V-o-WON array exhibits a small overpotential of 16 mV at the current density of 10 mA cm(-2) and a low Tafel slope of 33 mV per decade in alkaline media, accompanied by negligible loss upon a large current density over 100 h. Benefiting from outstanding electrocatalytic hydrogen evolution reaction performance and stability, this defective heterostructure could serve as a prominent alternative electrocatalyst for renewable energy applications.
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