Formation of supported nanoparticles from island thin films during ion etching

Pászti, Zoltán; Petö, G.; Horváth, Z.E.; Geszti, O.; Karacs, Albert; Guczi, L.

doi:10.1016/s0168-583x(00)00483-3

Cited by 12 publications

(5 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The etching procedure conducted here was primarily targeting the removal of adsorbed impurities and the NiO phase on the sample surface. , Because the screening agent of adsorbates and surface-separated NiO phase were substantially removed, a stronger resolved peak feature of higher oxidized Ni should increase accordingly. It should be noted that the Ar + etching procedure can partially purge the NiO phase in the LNO surface, but it also has a de-acidifying effect on the superficial layer of the TM oxides . The surface Ni with a higher oxidation state has a higher covalent capacity to lattice oxygen on the perovskite surface, which is in accordance with the promotion principles for the catalytic activity of perovskite oxides on the OER process .…”

Section: Resultssupporting

confidence: 64%

Understanding the Enhancement Mechanism of A-Site-Deficient La_xNiO₃ as an Oxygen Redox Catalyst

et al. 2020

View full text Add to dashboard Cite

Lanthanide perovskite oxides have attracted much attention as an oxygen reduction and evolution catalyst because of their high chemical stability and composition adjustability. A defect strategy has been applied to enhance their electrocatalytic activity with the modulation of the crystal/electronic structure. However, the intrinsic roles of the defects, particularly A-site vacancies, are poorly understood. Herein, we prepare La x NiO 3 with various ratios of A-site vacancies by a facile nonstoichiometric strategy, which has boosted the dual-function catalytic activity of LaNiO 3 . More importantly, the enhancement mechanism of A-site-deficient La x NiO 3 as an oxygen redox catalyst has been unveiled. Induced vacancy defects on the A sites raise a compression strain in the NiO 6 octahedron, exerting a positive enhancement on Ni−O covalency. Furthermore, the e g electron filling in the active cation Ni and the overlapping state of Ni 3d−O 2p hybridization have also been optimized, in which renovation will further boost the catalytic ability of oxygen redox processes. This work not only clarifies the intrinsic roles of A-site deficiency in the structure and electrocatalytic activities of perovskite oxides but also presents some insights into the design and exploration of high-activity catalysts by cation defect modulation.

show abstract

Section: Resultssupporting

confidence: 64%

Understanding the Enhancement Mechanism of A-Site-Deficient La_xNiO₃ as an Oxygen Redox Catalyst

et al. 2020

View full text Add to dashboard Cite

show abstract

“…While there is a general agreement on the large ones are related to ion induced dewetting, the small ones are discussed in terms of re-deposition 13 or produced under the surface by implantation in the substrate. 11,12,14 The latter explanation is the most likely when comparing these bimodal distributions imaged in plan-view to those reported for covered metal NPs produced by PLD and for which cross-section images clearly demonstrated the small NPs were inside the substrate. 8 In addition, sputtering of metal was generally observed and the experimentally determined sputtering yield (SY) was simulated using standard models that lead to values that were smaller than the experimental ones 7,10,15 and was found to increase with dose.…”

Section: Introductionmentioning

confidence: 57%

“…Ion bombardment of solid surfaces is known since very long to result in several surface modifications, the more widely studied ones being sputtering of atoms from the surface, implantation of species under the surface and surface damage by creating defects and/or erosion. 9 It has more recently received lot of attention as a means to produce metal NPs from a thin metal layer [10][11][12][13][14] or modify arrays of NPs. 15 In the former case, almost spherical NPs are produced and a bimodal distribution of large and small NPs is generally observed.…”

Section: Introductionmentioning

confidence: 99%

Importance of ion bombardment during coverage of Au nanoparticles on their structural features and optical response

Resta

Peláez

Afonso

2014

Journal of Applied Physics

View full text Add to dashboard Cite

This work studies the changes in the optical response and morphological features of 6 6 1 nm diameter Au nanoparticles (NPs) when covered by a layer of a-Al 2 O 3 by pulsed laser deposition (PLD). The laser fluence used for ablating the Al 2 O 3 target is varied in order to modify the kinetic energy (KE) of the species bombarding the NPs during their coverage. When the ion KE < 200 eV, the structural features and optical properties of the NPs are close to those of uncovered ones. Otherwise, a shift to the blue and a strong damping of the surface plasmon resonance is observed as fluence is increased. There are two processes responsible for these changes, both related to aluminum ions arriving to the substrate during the coverage process, i.e., sputtering of the metal and implantation of aluminum species in the metal. Both processes have been simulated using standard models for ion bombardment, the calculated effective implanted depths allow explaining the observed changes in the optical response, and the use of a size-dependent sputtering coefficient for the Au NPs predicts the experimental sputtering fractions. In spite of the work is based on PLD, the concepts investigated and conclusions can straightforwardly be extrapolated to other physical vapor deposition techniques or processes involving ion bombardment of metal NPs by ions having KE > 200 eV. V

show abstract

“…This effect could be attributed to the redistribution rather than to the narrowing of the 5d states [7][8][9][10][11]. The Au/FeO x /SiO 2 /Si(100) model system has gold in its zero valence state even during size reduction induced by Ar+ ion bombardment.…”

Section: Investigation On Model Au/fe 2 O 3 Systemmentioning

confidence: 99%

Gold catalyst research at the institute of Isotopes, Budapest

Guczi

2006

Gold Bull

View full text Add to dashboard Cite

Formation of supported nanoparticles from island thin films during ion etching

Cited by 12 publications

References 14 publications

Understanding the Enhancement Mechanism of A-Site-Deficient La_xNiO₃ as an Oxygen Redox Catalyst

Understanding the Enhancement Mechanism of A-Site-Deficient La_xNiO₃ as an Oxygen Redox Catalyst

Importance of ion bombardment during coverage of Au nanoparticles on their structural features and optical response

Gold catalyst research at the institute of Isotopes, Budapest

Contact Info

Product

Resources

About

Formation of supported nanoparticles from island thin films during ion etching

Cited by 12 publications

References 14 publications

Understanding the Enhancement Mechanism of A-Site-Deficient LaxNiO3 as an Oxygen Redox Catalyst

Understanding the Enhancement Mechanism of A-Site-Deficient LaxNiO3 as an Oxygen Redox Catalyst

Importance of ion bombardment during coverage of Au nanoparticles on their structural features and optical response

Gold catalyst research at the institute of Isotopes, Budapest

Contact Info

Product

Resources

About

Understanding the Enhancement Mechanism of A-Site-Deficient La_xNiO₃ as an Oxygen Redox Catalyst

Understanding the Enhancement Mechanism of A-Site-Deficient La_xNiO₃ as an Oxygen Redox Catalyst