Preparation of calcium tantalum oxynitride from layered oxide precursors to improve photocatalytic activity for hydrogen evolution under visible light

作者：Sasaki Ryo; Maeda Kazuhiko; Kako Yoko; Domen Kazunari^*

来源：Applied Catalysis B: Environmental , 2012, 128: 72-76.

DOI：10.1016/j.apcatb.2011.10.024

• Layered oxide
• Hydrogen production
• Oxynitride
• Photocatalyst
• Visible light
• Water splitting

A new precursor route to prepare calcium tantalum oxynitride (CaTaO2N) was explored in an attempt to improve the photocatalytic activity for H-2 evolution from water under visible light. CaTaO2N catalysts were prepared using either a layered metal oxide (e.g., RbCa2Ta3O10 or HCa2Ta3O10) or a bulk-type Ca-Ta oxide prepared by the polymerized complex (PC) method. CaTaO2N samples prepared from the layered oxides had a less-aggregated morphology and a bluer absorption edge than an analog from a PC-derived precursor, in addition to a lower density of anionic defects. Samples prepared from the layered oxide also showed an enhanced photocatalytic activity for H-2 evolution from an aqueous methanol solution under visible light (lambda > 420 nm), primarily because of their lower density of anionic defects and the enhanced driving force for surface redox reactions that resulted from their blue-shifted absorption edge.

• 出版日期2012-11-30