A novel preparation approach and denitrification performance of TiO₂/Fe⁰ photocatalysts

Abstract

Chemical vapor hydrolysis deposition (CVHD), a novel method for preparation of TiO₂/Fe⁰ is presented. In the method, tetrabutyl titanate (TBT) and sponge iron (Fe_s) are used as precursor and carrier, respectively. Especially, TBT was hydrolyzed slowly with the thin water vapor to create TiO₂ nanoparticles on the Fe_s carrier. The experiment showed that the optimal preparation conditions for TiO₂/Fe⁰ via CVHD were calcination temperature of 723 K and TiO₂-loading amount of 7.57%. The as-prepared TiO₂/Fe⁰ catalysts were evaluated by the catalytic reaction of nitrate reduction, and exhibited a higher catalytic activity and selectivity than the similar catalysts prepared with the typical methods of sol–gel or alkoxide hydrolysis precipitation. The present results demonstrate that the selective nitrate reduction over TiO₂/Fe⁰ catalysts with HCOOH as the hole scavenger, highlighting the validity of removal of aqueous nitrate by photocatalysis.

Keywords:

• Chemical vapor hydrolysis deposition (CVHD)
• Nitrate
• Photocatalysis
• TiO₂/Fe⁰

Acknowledgment

This work is supported by National Natural Science Foundation of China (No. 50309011), the Research project of Shannxi Province (2011K17-03-06) and the Scientific Research Foundation for the Returned Overseas Chinese Scholars (08501041585).