Ceria–Zirconia Particles Wrapped in a 2D Carbon Envelope: Improved Low‐Temperature Oxygen Transfer and Oxidation Activity. Issue 47 (8th October 2015)

• Record Type: Journal Article
• Authors: Aneggi, Eleonora; Rico‐Perez, Veronica; de Leitenburg, Carla; Maschio, Stefano; Soler, Lluís; Llorca, Jordi; Trovarelli, Alessandro
• Is Part Of: Angewandte Chemie international edition. Volume 54:Issue 47(2015)
• Page Start: 14040
• Page End: 14043
• Publication Date: 2015-10-08
• Subjects: ceria‐zirconia particles -- heterogeneous catalysis -- high‐energy milling -- oxygen storage -- soot combustion; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201507839
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Engineering the interface between different components of heterogeneous catalysts at nanometer level can radically alter their performances. This is particularly true for ceria‐based catalysts where the interactions are critical for obtaining materials with enhanced properties. Here we show that mechanical contact achieved by high‐energy milling of CeO2 –ZrO2 powders and carbon soot results in the formation of a core of oxide particles wrapped in a thin carbon envelope. This 2D nanoscale carbon arrangement greatly increases the number and quality of contact points between the oxide and carbon. Consequently, the temperatures of activation and transfer of the oxygen in ceria are shifted to exceptionally low temperatures and the soot combustion rate is boosted. The study confirms the importance of the redox behavior of ceria‐zirconia particles in the mechanism of soot oxidation and shows that the organization of contact points at the nanoscale can significantly modify the reactivity resulting in unexpected properties and functionalities. Abstract : Soot combustion : The intimate contact of ceria–zirconia particles with a thin carbon layer promoted the transfer of lattice/surface oxygen atoms. The oxidation temperatures of soot were significantly lowered (see picture).