Acta Phys. -Chim. Sin. ›› 2014, Vol. 30 ›› Issue (10): 1903-1908.doi: 10.3866/PKU.WHXB201407173

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Hydrogenated Rutile TiO2 Nanorods and Their Photocatalytic Activity

CUI Hai-Qin, JING Li-Qiang, XIE Ming-Zheng, LI Zhi-Jun   

  1. Key Laboratory of Functional Inorganic Materials Chemistry, Ministry of Education, School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, P. R. China
  • Received:2014-06-24 Revised:2014-07-15 Published:2014-09-30
  • Contact: JING Li-Qiang E-mail:jinglq@hlju.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21071048) and Research Project of the Ministry of Education of China (213011A).

Abstract:

TiO2 rutile nanorods were successfully synthesized by a hydrochloric acid-modified hydrothermal process, using butyl titanate as the titanium source, followed by hydrogenation treatment. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-Vis near infrared (NIR) diffuse reflection spectroscopy (UV- Vis- NIR DRS), electron paramagnetic resonance (EPR), surface photovoltage spectroscopy (SPS), and the photodegradation of gas-phase acetaldehyde and liquid-phase phenol to evaluate the photocatalytic activity of the catalysts. The results show that the photoresponse of TiO2 gradually expands from the ultraviolet region to the visible and near-infrared regions upon increasing the hydrogenation time at high temperature. Its color changed from white to gray, and this is attributed to the introduction of Ti3+ defects and oxygen vacancies. Based on surface photovoltage spectroscopy responses and the amount of hydroxyl radicals produced, hydrogenation treatment promoted the photogenerated charge separation significantly. This is responsible for the improved photocatalytic degradation activity toward gasphase acetaldehyde and liquid-phase phenol under visible or ultraviolet irradiation. Therefore, a specific amount of defects and/or vacancies can induce new and appropriate surface states below the conduction band of the TiO2 samples. However, if the amount of introduced defects or vacancies is too high, low-level surface states are produced and this is not favorable for photogenerated charge separation, and detrimental to photocatalytic reactions.

Key words: TiO2, Hydrogenation treatment, Defect, Photogenerated charge separation, Photocatalysis

MSC2000: 

  • O643