Open AccessEnhancing the Catalytic Activity of Palladium Nanoparticles via Sandwich-Like Confinement by Thin Titanate Nanosheets
Author(s) -
Kevin Ament,
Daniel R. Wagner,
Thomas Götsch,
Takayuki Kikuchi,
Jutta Kröhnert,
Annette Trunschke,
Thomas Lunkenbein,
Takayoshi Sasaki,
Josef Breu
Publication year - 2021
Publication title -
acs catalysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.898
H-Index - 198
ISSN - 2155-5435
DOI - 10.1021/acscatal.1c00031
Subject(s) - materials science , x ray photoelectron spectroscopy , noble metal , nanoparticle , titanate , chemical engineering , nanomaterial based catalyst , catalysis , palladium , fourier transform infrared spectroscopy , mesoporous material , metal , nanotechnology , inorganic chemistry , chemistry , composite material , organic chemistry , ceramic , engineering , metallurgy
As atomically thin oxide layers deposited on flat (noble) metal surfaces have been proven to have a significant influence on the electronic structure and thus the catalytic activity of the metal, we sought to mimic this architecture at the bulk scale. This could be achieved by intercalating small positively charged Pd nanoparticles of size 3.8 nm into a nematic liquid crystalline phase of lepidocrocite-type layered titanate. Upon intercalation the galleries collapsed and Pd nanoparticles were captured in a sandwichlike mesoporous architecture showing good accessibility to Pd nanoparticles. On the basis of X-ray photoelectron spectroscopy (XPS) and CO diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) Pd was found to be in a partially oxidized state, while a reduced Ti species indicated an electronic interaction between nanoparticles and nanosheets. The close contact of titanate sandwiching Pd nanoparticles, moreover, allows for the donation of a lattice oxygen to the noble metal (inverse spillover). Due to the metal-support interactions of this peculiar support, the catalyst exhibited the oxidation of CO with a turnover frequency as high as 0.17 s -1 at a temperature of 100 °C.