Tunable Oxygen Activation for Catalytic Organic Oxidation: Schottky Junction versus Plasmonic Effects

DOI number:10.1002/anie.201309660

Journal:ANGEWANDTE CHEMIE-INTERNATIONAL EDITION

Place of Publication:WEINHEIM

Key Words:heterogeneous catalysis; oxygen activation; palladium; plasmonics; titania

Abstract:The charge state of the Pd surface is a critical parameter in terms of the ability of Pd nanocrystals to activate O-2 to generate a species that behaves like singlet O-2 both chemically and physically. Motivated by this finding, we designed a metal-semiconductor hybrid system in which Pd nanocrystals enclosed by {100} facets are deposited on TiO2 supports. Driven by the Schottky junction, the TiO2 supports can provide electrons for metal catalysts under illumination by appropriate light. Further examination by ultrafast spectroscopy revealed that the plasmonics of Pd may force a large number of electrons to undergo reverse migration from Pd to the conduction band of TiO2 under strong illumination, thus lowering the electron density of the Pd surface as a side effect. We were therefore able to rationally tailor the charge state of the metal surface and thus modulate the function of Pd nanocrystals in O-2 activation and organic oxidation reactions by simply altering the intensity of light shed on Pd-TiO2 hybrid structures.

Co-author:Long, Ran, Mao, Keke, Gong, Ming, Zhou, Shan, Hu, Jiahua, Zhi, Min, You, Yang, Bai, Song, Jiang, Jun, Zhang, Qun, Wu, Xiaojun, Xiong, Yujie

First Author:Long, Ran

Correspondence Author:Zhang, Q, Xiong, YJ

Document Code:WOS:000332747700029

Document Type:Article

Volume:53

Issue:12

Page Number:3205-3209

ISSN No.:1433-7851

Translation or Not:no