Unusual Catalytic Properties of High-Energetic-Facet Polar Metal Oxides

Li, Y.; Tsang, Shik Chi Edman

doi:10.1021/acs.accounts.0c00641

Cited by 18 publications

(9 citation statements)

References 52 publications

(154 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, the surface state of ZnO nanosheet also plays a vital role. It may be more inclined to expose the O-termination (00) polar plane (O-ZnO (00)) after annealing at elevated temperature in air, which possess more surface oxygen vacancy. − The formation of oxygen vacancy could facilitate the activation of O 2 molecules and promotes the improvement of CO oxidation performance. In order to further explore the stability of the catalysts, in situ TEM was used to unravel the structural features of Pd/ZnO catalyst under real reaction conditions, as shown in Figure b,d.…”

Section: Resultsmentioning

confidence: 99%

Sinter Resistance and Activity Enhancement via a Facet-Dependent Metal–Support Interaction of Pd/ZnO Catalysts in CO Oxidation

Niu

Wang

et al. 2021

J. Phys. Chem. C

View full text Add to dashboard Cite

Metal−support interaction (MSI) has been extensively investigated regarding its structural and catalytic modification in heterogeneous catalysts. Herein, we reveal how facet-dependent MSI impacts on the structure and performance of Pd/ZnO in the CO oxidation reaction. ZnO nanosheets with orthohexagonal shape which are exposed mainly with {001} facets exhibit remarkable thermal stability under air atmosphere until 600 °C, while ZnO nanorods bounded with {100} facets transform at 400 °C and totally change after calcination at 600 °C. Thus, the Pd species supported on ZnO nanorods and nanosheets also display different sintering behaviors after thermal treatment, and the particle size of Pd grows from 1.1 to 5.7 nm on {100} facets while it keeps high-dispersion on {001} facets after 600 °C calcination. In situ transmission electron microscopy was used to visualize the sintering process, demonstrating that Pd displays the Ostwald ripening and particle migration coalescence mechanism on ZnO {100} facets, while shows extraordinary stability on ZnO {001} facets. Therefore, Pd supported on ZnO nanorod exhibits deactivation behavior after high temperature treatment in CO oxidation, during which the T 50 delays from 106 to 120 and 145 °C after 200, 400, and 600 °C calcination. Interestingly, Pd on ZnO nanosheet shows obvious activity enhancement from 137 to 90 and 75 °C of T 50 after the same treatment, which is ascribed to the synergy between Pd and ZnO {001} facets during catalysis. This work gives indepth understanding of the facet-dependent MSI of Pd/ZnO catalysts, and it sheds light on the rational design of heterogeneous catalysts with high efficiency and sinter resistance.

show abstract

Section: Resultsmentioning

confidence: 99%

Sinter Resistance and Activity Enhancement via a Facet-Dependent Metal–Support Interaction of Pd/ZnO Catalysts in CO Oxidation

Niu

Wang

et al. 2021

J. Phys. Chem. C

View full text Add to dashboard Cite

show abstract

“…41 Furthermore, high-energy facets such as {101̅ m} (m = 0, 1, 2, or 3) and {21̅ 1̅ n} (n = 0, 1, 2, or 3) can contribute to the easy activation of CO 2 on the surface. 42 These semipolar surfaces could help tailor the binding energy of O 1s to enhance the electron transfer between ZnO and Cu nanoparticles as a result of strong metal−support interaction. 43,44…”

Section: Resultsmentioning

confidence: 99%

Unraveling Anisotropic and Pulsating Etching of ZnO Nanorods in Hydrochloric Acid via Correlative Electron Microscopy

Liu

Zhu

et al. 2023

ACS Nano

View full text Add to dashboard Cite

Despite much technical progress achieved so far, the exact surface and shape evolution during wet chemical etching is less unraveled, especially in ionically bonded ceramics. Herein, by using in situ liquid cell transmission electron microscopy, a repeated two-stage anisotropic and pulsating periodic etching dynamic is discovered during the pencil shape evolution of a single crystal ZnO nanorod in aqueous hydrochloric acid. Specifically, the nanopencil tip shrinks at a slower rate along [0001̅] than that along the ⟨101̅0⟩ directions, resulting in a sharper ZnO pencil tip. Afterward, rapid tip dissolution happens due to accelerated etching rates along various crystal directions. Concurrently, the vicinal base region of the original nanopencil tip emerges as a new tip followed by the repeated sequence of tip shrinking and removal. The high-index surfaces, such as {101̅m} (m = 0, 1, 2, or 3) and {21̅ 1̅n} (n = 0, 1, 2, or 3), are found to preferentially expose in different ratios. Our 3D electron tomography, convergent beam electron diffraction, middle-angle bright-field STEM, and XPS results indicate the dissociative Cl– species were bound to the Zn-terminated tip surfaces. Furthermore, DFT calculation suggests the preferential Cl– passivation over the {101̅1} and (0001) surfaces of lower energy than others, leading to preferential surface exposures and the oscillatory variation of different facet etching rates. The boosted reactivity due to high-index nanoscale surface exposures is confirmed by comparatively enhanced chemical sensing and CO2 hydrogenation activity. These findings provide an in-depth understanding of anisotropic wet chemical etching of ionic nanocrystals and offer a design strategy for advanced functional materials.

show abstract

“…In some examples, nanomaterial with exposed special fact can be controllably synthesized by using one or more kind's surfactants, which selected adsorption on the special planes and then changed the inherent growth direction. [98][99][100] Then these nanomaterials can be employed as catalysts in the catalytic field, such as photocatalytic, [101][102][103] water splitting, [104,105] electrooxidation, [106,107] and DSSCs. [108,109] So, it is reasonable to expect the low-cost metal chalcogenides with special facets can deliver satisfactory performance.…”

Section: Development Of Noble Metal-free Chalcogenides With Well-controlled Facetsmentioning

confidence: 99%

Review on Low‐Cost Counter Electrode Materials for Dye‐Sensitized Solar Cells: Effective Strategy to Improve Photovoltaic Performance

Wang

Zhao

Kan

et al. 2021

Adv Materials Inter

View full text Add to dashboard Cite

The photoelectric conversion efficiency (PCE) of dye‐sensitized solar cells (DSSCs) can be remarkably improved by optimizing the catalytic activity and charge transfer ability of the counter electrode (CE) materials. The attentive hotspots of CE catalysts for DSSCs are to design multifunctional materials that balance the fabrication cost, environmental friendliness, PCE, and electrochemical stability, then to achieve the substitution of the benchmark Pt. In this review, the four effective strategies are highlighted for further improving the photovoltaic performance of the DSSCs based on low‐cost CE materials, such as heteroatom‐doped materials, development of noble metal‐free chalcogenides with well‐controlled facets, construction of heterostructure, and synthesis of composites with a synergistic effect. In some typical examples, the influence of these strategies on catalytic activity, charge transfer ability, and reaction mechanism are elucidated by the theoretical calculation. Then the research opportunities and the challenges for the high‐efficiency DSSCs based on low‐cost CE materials are presented.

show abstract

Unusual Catalytic Properties of High-Energetic-Facet Polar Metal Oxides

Cited by 18 publications

References 52 publications

Sinter Resistance and Activity Enhancement via a Facet-Dependent Metal–Support Interaction of Pd/ZnO Catalysts in CO Oxidation

Sinter Resistance and Activity Enhancement via a Facet-Dependent Metal–Support Interaction of Pd/ZnO Catalysts in CO Oxidation

Unraveling Anisotropic and Pulsating Etching of ZnO Nanorods in Hydrochloric Acid via Correlative Electron Microscopy

Review on Low‐Cost Counter Electrode Materials for Dye‐Sensitized Solar Cells: Effective Strategy to Improve Photovoltaic Performance

Contact Info

Product

Resources

About