The reactivity of atomically dispersed Pt(2+) species on the surface of nanostructured CeO2 films and the mechanism of H2 activation on these sites have been investigated by means of synchrotron radiation photoelectron spectroscopy and resonant photoemission spectroscopy in combination with density functional calculations. Isolated Pt(2+) sites are found to be inactive towards H2 dissociation due to high activation energy required for H-H bond scission. Trace amounts of metallic Pt are necessary to initiate H2 dissociation on Pt-CeO2 films. H2 dissociation triggers the reduction of Ce(4+) cations which, in turn, is coupled with the reduction of Pt(2+) species. The mechanism of Pt(2+) reduction involves reverse oxygen spillover and formation of oxygen vacancies on Pt-CeO2 films. Our calculations suggest the existence of a threshold concentration of oxygen vacancies associated with the onset of Pt(2+) reduction.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/c6cp00627b | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Metal (Au, Pt, Pd, Ni) Bis(dithiolene) complexes as dual-action agents combating cancer and trypanosomatid infections.
J Inorg Biochem
March 2025
Centro de Ciências e Tecnologias Nucleares and Departamento de Engenharia e Ciências Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 2695-066 Bobadela LRS, Portugal.
Cancer and infection diseases pose severe threats to public health worldwide stressing the need for more effective and efficient treatments. Thus, the search for broad-spectrum activity drugs seems justifiable and urgent. Herein, we investigate the anticancer and antitrypanosomatid (anti-Trypanosoma cruzi) activities of eight monoanionic metal bis(dithiolene) complexes, [PhP][M(R-thiazdt)] with M = Au, Pt, Pd, Ni, containing N-alkyl-1,3-thiazoline-2-thione dithiolene ligands (R-thiazdt) with different alkyl groups (R = Et, tBu).
View Article and Find Full Text PDFEfficient regulation of surface hydroxyl groups on a Pt/Na/AC catalyst using two-step nonthermal plasma for high formaldehyde oxidation performance.
Nanoscale
December 2024
Institute of Environmental Science, Fudan University, Shanghai 200433, People's Republic of China.
A novel catalyst was fabricated using a two-step nonthermal plasma method by regulating surface hydroxyl groups on Na/activated carbon (AC) with 0.1 wt% Pt loading (Pt/Na/AC (P&P)) and achieved high formaldehyde (HCHO) oxidation performance at ambient temperature. Based on characterization results, we found that in the first step of nonthermal plasma treatment under argon-water, the proportion of terminal OH groups (ter-OH groups) evidently increased.
View Article and Find Full Text PDFConvergent Active Site Evolution in Platinum Single Atom Catalysts for Acetylene Hydrochlorination and Implications for Toxicity Minimization.
ACS Catal
September 2024
Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1, Zürich 8093, Switzerland.
Platinum single atoms anchored onto activated carbon enable highly stable Hg-free synthesis of vinyl chloride (VCM) via acetylene hydrochlorination. Compared to gold-based alternatives, platinum catalysts are in initial phases of development. Most synthetic approaches rely on chloroplatinic acid, presenting opportunities to explore other precursors and their impact on catalyst structure, reactivity, and toxicity aspects.
View Article and Find Full Text PDFDinuclear Cyclometalated Pincer Nickel(II) Complexes with Metal-Metal-to-Ligand Charge Transfer Excited States and Near-Infrared Emission.
Angew Chem Int Ed Engl
January 2025
Department of Chemistry, State Key Laboratory of Synthetic Chemistry, CAS-HKU Joint Laboratory on New Materials, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.
Facile non-radiative decay of low-lying metal-centered (MC) dd excited states has been well documented to pose a significant obstacle to the development of phosphorescent Ni complexes due to substantial structural distortions between the dd excited state and the ground state. Herein, we prepared a series of dinuclear Ni complexes by using strong σ-donating carbene-phenyl-carbene (C C C) pincer ligands, and prepared their dinuclear Pt and Pd analogues. Dinuclear Ni complexes bridged by formamidinate/α-carbolinato ligand exhibit short Ni-Ni distances of 2.
View Article and Find Full Text PDFInnovative Charge-Tuning for Highly Dispersed Pt Catalysts: Achieving Deep CO Removal in Industrial H Purification for Fuel Cells.
ACS Appl Mater Interfaces
October 2024
Beijing Institute of Smart Energy, Beijing 102209, China.
Proton exchange membrane fuel cells have strict requirements for the CO concentration in H-rich fuel gas. Here, from the perspective of industrial practicability, a highly dispersed Pt catalyst (2-4 nm) supported on activated carbon (AC), which was modified by electronic promoters (K) and structural promoters (isopropanol), is studied in detail. Compared with traditional metal oxide supports, the K-Pt/AC catalysts, which benefit from the tuned charge distribution, achieve a significant reduction of CO (from 1% to <0.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!