Tuning oxide activity through modification of the crystal and electronic structure: from strain to potential polymorphs.
Phys Chem Chem Phys
; 17(43): 28943-9, 2015 Nov 21.
Article
em En
| MEDLINE
| ID: mdl-26455918
Discovering new materials with tailored chemical properties is vital for advancing key technologies in catalysis and energy conversion. One strategy is the modification of a material's crystal structure, and new methods allow for the synthesis and stabilization of potential materials in a range of crystal polymorph structures. We assess the potential reactivity of four metastable oxide polymorphs of MO2 (M = Ru, Rh, Pt, Ir) transition metal oxides. In spite of the similar local geometry and coordination between atoms in the metastable polymorphic and stable rutile structure, we find that polymorph reactivities cannot be explained by strain alone and offer tunable reactivity and increased stability. Atom-projected density of states reveals that the unique reactivity of polymorphs are caused by a redistribution of energy levels of the t2g-states. This structure-activity relationship is induced by slight distortions to the M-O bonds in polymorphic structures and is unattainable by strain. We predict columbite IrO2 to be more active than rutile IrO2 for oxygen evolution.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Phys Chem Chem Phys
Assunto da revista:
BIOFISICA
/
QUIMICA
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Estados Unidos