Tuning reactivity layer-by-layer: Formic acid activation on Ag/Pd(111)

Karatok M., Duanmu K., O'Connor C. R., Boscoboinik J. A., Sautet P., Madix R. J., ...More

Chemical Science, vol.11, no.25, pp.6492-6499, 2020 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 11 Issue: 25
  • Publication Date: 2020
  • Doi Number: 10.1039/d0sc01461c
  • Journal Name: Chemical Science
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), Biotechnology Research Abstracts, Chimica, Compendex, Metadex, Directory of Open Access Journals
  • Page Numbers: pp.6492-6499
  • Hacettepe University Affiliated: No


The potential for tuning the electronic structure of materials to control reactivity and selectivity in heterogenous catalysis has driven interest in ultrathin metal films which may differ from their bulk form. Herein, a 1-atomic layer Ag film on Pd(111) (Ag/Pd(111)) is demonstrated to have dramatically different reactivity towards formic acid compared to bulk Ag. Formic acid decomposition is of interest as a source of H2 for fuel cell applications and modification of Pd by Ag reduces poisoning by CO and increases the selectivity for H2 formation. Formic acid reacts below room temperature on the 1-atomic layer Ag film, whereas no reaction occurs on pristine bulk Ag. Notably, 2 monolayer films of Ag again become unreactive towards formic acid, indicating a reversion to bulk behavior. A combination of infrared reflection absorption spectroscopy (IRRAS), X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) was used to establish that the Ag monolayer is continuous and electronically modified compared to bulk Ag. The work establishes a demonstration of the altered electronic structure of Ag monolayers on Pd(111) and an associated change in reactivity. The effect on reactivity only persists for the first layer, demonstrating the need for precise control of materials to exploit the modification in electronic properties.