1 research outputs found
Revealing the Size Effect of Ceria Nanocube-Supported Platinum Nanoparticles in Complete Propane Oxidation
The
elimination of propane is one of the key tasks in
reducing
volatile organic compounds (VOCs) and automotive exhaust emissions.
The platinum nanoparticle (NP) is a promising catalyst for propane
oxidation, while the study of its structural characteristics and functionality
remains in its infancy. In this work, we synthesized the nanocubes
CeO2 with a well-defined (100) facet supporting Pt NPs
with various sizes, from 1.3 to 7 nm, and systematically investigated
the effect of the Pt size on complete propane oxidation efficiency.
In particular, CeO2(100) supported Pt NPs smaller than
4 nm promote the formation of positively charged Pt sites, which hinder
the adsorption and activation of propane and reduce the intrinsic
activity for propane oxidation. Consequently, within this size range,
the catalytic performance is primarily influenced by the electronic
state of the Pt species, with metallic Pt being identified as the
active site for the reaction. Conversely, as the particle size exceeds
4 nm, metallic Pt particles become dominant and the geometric structure
starts to influence the activity as well. Such entanglement of electronic
and geometric factors gives rise to a volcano relationship between
reaction rates and Pt particle sizes ranging from 1.3 to 7 nm, while
an increased correlation can be observed between the turnover frequencies
and the particle sizes in this range. This knowledge can guide the
synthesis of highly active catalysts, enabling the efficient oxidation
of VOCs with reduced precious metal loadings