Multi-shelled CeO₂ hollow microspheres as superior photocatalysts for water oxidation

• Published in: Nanoscale Vol. 6; no. 8; p. 4072
• Main Authors: Qi, Jian, Zhao, Kun, Li, Guodong, Gao, Yan, Zhao, Huijun, Yu, Ranbo, Tang, Zhiyong
• Format: Journal Article
• Language: English
• Published: England 21-04-2014
• Subjects: Catalysis; Cerium - chemistry; Microspheres; Oxidation-Reduction; Oxygen - chemistry; Photochemical Processes; Water - chemistry
• ISSN: 2040-3372
• DOI: 10.1039/c3nr06822f

A general self-templating method is introduced to construct triple-shelled CeO₂ hollow microspheres, which are composed of tiny CeO₂ nanoparticles. When the triple-shelled CeO₂ hollow microspheres are used as photocatalysts for direct water oxidation with AgNO₃ as the electron scavenger, excellent activity and enhanced stability for O₂ evolution are achieved, in contrast with commercial CeO₂ nanoparticles, single-shelled CeO₂ hollow microspheres and double-shelled CeO₂ hollow microspheres. Such an outstanding performance is attributed to the unique properties of the triple-shelled CeO₂ hollow microspheres including more efficient multiple reflections of the incident light by the inner shells, the larger surface area and more active sites for improving separation of electron-hole pairs, and the more curved surfaces unfavorable for deposition of in situ generated Ag nanoparticles.