Controlling Reaction Selectivity through the Surface Termination of Perovskite Catalysts. Issue 33 (19th July 2017)

• Record Type: Journal Article
• Authors: Polo‐Garzon, Felipe; Yang, Shi‐Ze; Fung, Victor; Foo, Guo Shiou; Bickel, Elizabeth E.; Chisholm, Matthew F.; Jiang, De‐en; Wu, Zili
• Is Part Of: Angewandte Chemie international edition. Volume 56:Issue 33(2017)
• Page Start: 9820
• Page End: 9824
• Publication Date: 2017-07-19
• Subjects: acid/base catalysis -- dehydration/dehydrogenation -- heterogeneous catalysis -- perovskites -- surface termination; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201704656
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Although perovskites have been widely used in catalysis, tuning of their surface termination to control reaction selectivity has not been well established. In this study, we employed multiple surface‐sensitive techniques to characterize the surface termination (one aspect of surface reconstruction) of SrTiO3 (STO) after thermal pretreatment (Sr enrichment) and chemical etching (Ti enrichment). We show, by using the conversion of 2‐propanol as a probe reaction, that the surface termination of STO can be controlled to greatly tune catalytic acid/base properties and consequently the reaction selectivity over a wide range, which is not possible with single‐metal oxides, either SrO or TiO2 . Density functional theory (DFT) calculations explain well the selectivity tuning and reaction mechanism on STO with different surface termination. Similar catalytic tunability was also observed on BaZrO3, thus highlighting the generality of the findings of this study. Abstract : It's what's on the surface that counts : Controlling the surface termination of SrTiO3 by thermal pretreatment (Sr enrichment) and chemical etching (Ti enrichment) enabled the catalytic selectivity for the conversion of 2‐propanol to be tuned over a wide range. The findings have significant implications for catalysis by mixed oxides, the surface and bulk compositions of which can differ depending on treatment and reaction conditions.