A Ni(OH)(2)-modified Ti-doped alpha-Fe2O3 photoanode for improved photoelectrochemical oxidation of urea: the role of Ni(OH)(2) as a cocatalyst

作者：Xu, Dandan; Fu, Zewen; Wang, Dejun; Lin, Yanhong; Sun, Yanjun; Meng, Dedong; Xie, Teng Feng^*

来源：Physical Chemistry Chemical Physics, 2015, 17(37): 23924-23930.

DOI：10.1039/c5cp03310a

• ATOMIC LAYER DEPOSITION
• WATER OXIDATION
• NANOTUBE ARRAYS
• HEMATITE
• LIGHT
• BEHAVIOR
• HETEROJUNCTION
• DEGRADATION
• PERFORMANCE
• CATALYST

For semiconductor-based PEC systems, loading an appropriate cocatalyst on a semiconductor (such as a solar-active material) can significantly improve the PEC activity due to the suppression of photogenerated charge recombination. But there is little direct information about the role of a cocatalyst in the spatial separation of photogenerated charge carriers. In our work, a combination of surface photovoltage spectroscopy (SPS), transient photovoltage (TPV) technique, photoelectrochemical impedance spectroscopy (PEIS) and transient photocurrent measurements was used to study the real role of Ni(OH)(2) as a cocatalyst for the enhanced PEC performance of Ni(OH)(2)-modified Ti-doped alpha-Fe2O3. It was found that Ni(OH)(2) as a hole storage layer enhances the separation of photogenerated charge carriers and increases the lifetime of holes, which contributed to the enhanced photocurrent. In addition, Ni(OH)(2) is a good cocatalyst for urea oxidation which suppresses the over-potential, resulting in a negative shift of the onset potential.

• 出版日期2015
• 单位吉林大学; 清华大学